KR20230096816A - Method and apparatus for transmission and reception based on predicted transmission configuration information in wireless communication systems - Google Patents

Abstract

The present invention relates to a communication technique that combines a 5G communication system with an IoT technology to support a higher data transmission rate after a 4G system and a system thereof. The present invention can be applied to intelligent services (eg, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety related services, etc.) based on a 5G communication technology and an IoT-related technology. According to the present invention, disclosed is a coverage increasing method for a PDCCH in a wireless communication system.

Description

Transmission and reception method and apparatus based on predicted transmission setting information in a wireless communication system

This disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a transmission/reception method based on predicted transmission setting information in a wireless communication system and an apparatus capable of performing the same.

5G mobile communication technology defines a wide frequency band to enable fast transmission speed and new services. It can also be implemented in the ultra-high frequency band ('Above 6GHz') called Wave. In addition, in the case of 6G mobile communication technology, which is called a system after 5G communication (Beyond 5G), in order to achieve transmission speed that is 50 times faster than 5G mobile communication technology and ultra-low latency reduced to 1/10, tera Implementations in Terahertz bands (eg, such as the 3 Terahertz (3 THz) band at 95 GHz) are being considered.

In the early days of 5G mobile communication technology, there was a need for enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine-type communications (mMTC). Beamforming and Massive MIMO to mitigate the path loss of radio waves in the ultra-high frequency band and increase the propagation distance of radio waves, with the goal of satisfying service support and performance requirements, and efficient use of ultra-high frequency resources Various numerology support (multiple subcarrier interval operation, etc.) and dynamic operation for slot format, initial access technology to support multi-beam transmission and broadband, BWP (Band-Width Part) definition and operation, large capacity New channel coding methods such as LDPC (Low Density Parity Check) code for data transmission and Polar Code for reliable transmission of control information, L2 pre-processing, and dedicated services specialized for specific services Standardization of network slicing that provides a network has been progressed.

Currently, discussions are underway to improve and enhance performance of the initial 5G mobile communication technology in consideration of the services that the 5G mobile communication technology was intended to support. NR-U (New Radio Unlicensed) for the purpose of system operation that meets various regulatory requirements in unlicensed bands ), NR terminal low power consumption technology (UE Power Saving), non-terrestrial network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with the terrestrial network is impossible, positioning, etc. Physical layer standardization of the technology is in progress.

In addition, IAB (Industrial Internet of Things (IIoT)), which provides nodes for expanding network service areas by integrating wireless backhaul links and access links, to support new services through linkage and convergence with other industries (Industrial Internet of Things, IIoT) Integrated Access and Backhaul), Mobility Enhancement technology including conditional handover and Dual Active Protocol Stack (DAPS) handover, 2-step random access that simplifies the random access procedure (2-step RACH for Standardization in the field of air interface architecture/protocol for technologies such as NR) is also in progress, and 5G　baseline for grafting Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies Standardization in the field of system architecture/service is also in progress for an architecture (eg, service based architecture, service based interface), mobile edge computing (MEC) for which services are provided based on the location of a terminal, and the like.

When such a 5G mobile communication system is commercialized, the explosively increasing number of connected devices will be connected to the communication network, and accordingly, it is expected that the function and performance enhancement of the 5G mobile communication system and the integrated operation of connected devices will be required. To this end, augmented reality (AR), virtual reality (VR), mixed reality (MR), etc. to efficiently support extended reality (XR), artificial intelligence (AI) , AI) and machine learning (ML), new research on 5G performance improvement and complexity reduction, AI service support, metaverse service support, and drone communication will be conducted.

In addition, the development of such a 5G mobile communication system is a new waveform, Full Dimensional MIMO (FD-MIMO), and Array Antenna for guaranteeing coverage in the terahertz band of 6G mobile communication technology. , multi-antenna transmission technologies such as large scale antennas, metamaterial-based lenses and antennas to improve coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), RIS ( Reconfigurable Intelligent Surface) technology, as well as full duplex technology to improve frequency efficiency and system network of 6G mobile communication technology, satellite, and AI (Artificial Intelligence) are utilized from the design stage and end-to-end (End-to-End) -to-End) Development of AI-based communication technology that realizes system optimization by internalizing AI-supported functions and next-generation distributed computing technology that realizes complex services beyond the limits of terminal computing capabilities by utilizing ultra-high-performance communication and computing resources could be the basis for

Based on the above discussion, the present disclosure provides an apparatus and method capable of effectively providing services in a mobile communication system.

In addition, the present disclosure provides a method and apparatus for previously setting a beam or beam candidate set to be applied to a specific channel.

In addition, the present disclosure provides a method and apparatus for reporting CSI for a plurality of points in time on a time axis.

A control signal processing method in a wireless communication system according to the present disclosure for solving the above problems includes receiving a first control signal transmitted from a base station, processing the received first control signal, and transmitting a second control signal generated based on the processing to the base station.

An embodiment of the present disclosure can effectively provide a service in a mobile communication system.

In addition, an embodiment of the present disclosure can reduce the number of times of unnecessary physical downlink control channel (PDCCH) decoding of a UE by previously setting a beam or a beam candidate set to be applied to a specific channel.

In addition, an embodiment of the present disclosure can reduce downlink control information (DCI) overhead by previously setting a beam or beam candidate set to be applied to a specific channel.

In addition, an embodiment of the present disclosure can reduce the number of unnecessary beam switching of a base station and a terminal by setting a beam or a beam candidate set to be applied to a specific channel in advance.

In addition, the embodiment of the present disclosure can efficiently check and use a channel state by predicting and/or reporting CSI for a plurality of points in time on the time axis.

1 is a diagram illustrating a basic structure of a time-frequency domain in a wireless communication system according to an embodiment of the present disclosure.
2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to an embodiment of the present disclosure.
3 is a diagram illustrating an example of setting a bandwidth portion in a wireless communication system according to an embodiment of the present disclosure.
4 is a diagram illustrating an example of setting a control region of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.
5A is a diagram illustrating a structure of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.
5B is a diagram illustrating a case where a terminal can have a plurality of PDCCH monitoring positions in a slot in a wireless communication system according to an embodiment of the present disclosure through a span.
6 is a diagram illustrating an example of a DRX operation in a wireless communication system according to an embodiment of the present disclosure.
7 is a diagram illustrating an example of base station beam allocation according to TCI state setting in a wireless communication system according to an embodiment of the present disclosure.
8 is a diagram illustrating an example of a TCI state allocation method for a PDCCH in a wireless communication system according to an embodiment of the present disclosure.
9 is a diagram illustrating a TCI indication MAC CE signaling structure for PDCCH DMRS in a wireless communication system according to an embodiment of the present disclosure.
10 is a diagram illustrating an example of beam configuration of a control resource set and a search space in a wireless communication system according to an embodiment of the present disclosure.
11 is a diagram for explaining a method for transmitting and receiving data by a base station and a terminal in consideration of a downlink data channel and a rate matching resource in a wireless communication system according to an embodiment of the present disclosure.
12 is a diagram for explaining a method for selecting a receivable control resource set in consideration of priority when a terminal receives a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.
13 is a diagram illustrating an example of frequency axis resource allocation of a PDSCH in a wireless communication system according to an embodiment of the present disclosure.
14 is a diagram illustrating an example of time axis resource allocation of a PDSCH in a wireless communication system according to an embodiment of the present disclosure.
15 is a diagram illustrating an example of time axis resource allocation according to subcarrier intervals of a data channel and a control channel in a wireless communication system according to an embodiment of the present disclosure.
16 illustrates a process for configuring and activating a PDSCH beam.
17 is a diagram illustrating an example of PUSCH repeated transmission type B in a wireless communication system according to an embodiment of the present disclosure.
18 is a diagram illustrating a radio protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation in a wireless communication system according to an embodiment of the present disclosure.
19 is a diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.
20 is a diagram illustrating an example of configuration of downlink control information (DCI) for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.
21 is a diagram illustrating an Enhanced PDSCH TCI state activation/deactivation MAC-CE structure.
22 is a diagram illustrating an RLM RS selection process according to an embodiment of the present disclosure.
23 is a diagram illustrating a preset-based control scheme of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure.
24 is a diagram illustrating an operation of a base station for a preset-based control method of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure.
25 is a diagram illustrating an operation of a terminal in relation to a preset based control method of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure.
26 is a diagram illustrating a TCI candidate presetting and instruction-based transmit/receive beam control scheme according to an embodiment of the present disclosure.
27 is a diagram illustrating operations of a base station for a TCI candidate presetting and indication-based transmit/receive beam control scheme according to an embodiment of the present disclosure.
28 is a diagram illustrating operations of a terminal in relation to TCI candidate presetting and indication-based transmit/receive beam control method according to an embodiment of the present disclosure.
29 is a diagram illustrating a structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.
30 is a diagram illustrating a structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

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

In describing the embodiments, descriptions of technical contents 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 it by omitting unnecessary description.

For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In each figure, the same reference number is given to the same or corresponding component.

Advantages and features of the present disclosure, and methods of achieving them, will become clear 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 and may be implemented in various different forms, only the present embodiments make the disclosure of the present disclosure complete, and common knowledge in the art to which the present disclosure belongs. It is provided to fully inform the person who has the scope of the disclosure, and the disclosure is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification. In addition, in describing 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 will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present disclosure, which may vary according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, a base station is a subject that performs resource allocation of a terminal, and may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing communication functions. In the present disclosure, downlink (DL) is a radio transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a radio transmission path of a signal transmitted from a terminal to a base station. In addition, although an LTE or LTE-A system 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, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included in this, and the following 5G may be a concept including existing LTE, LTE-A and other similar services there is. In addition, the present disclosure can be applied to other communication systems through some modifications within a range that does not greatly deviate from the scope of the present disclosure as determined by those skilled in the art.

At this time, it will be understood that each block of the process flow chart diagrams and combinations of the flow chart diagrams can 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, so that the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates means to perform functions. These computer program instructions may also be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular way, such that the computer usable or computer readable memory The instructions stored in are also capable of producing an article of manufacture containing instruction means that perform the functions described in the flowchart block(s). The computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to generate computer or other programmable data processing equipment. Instructions for performing processing equipment may also 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 possible for the functions mentioned in the blocks to occur out of order. For example, it is possible that two blocks shown in succession may in fact be performed substantially concurrently, or that the blocks may sometimes be performed in reverse order depending on their function.

At this time, 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. '~bu' may be configured to be in an addressable storage medium and may be configured to reproduce one or more processors. Therefore, as an example, '~unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. Functions provided within components and '~units' may be combined into smaller numbers 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 a secure multimedia card. Also, in the embodiment, '~ unit' may include one or more processors.

The wireless communication system has moved away from providing voice-oriented services in the early days and, 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, a broadband wireless network that provides high-speed, high-quality packet data services. 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) method is employed in downlink (DL), and SC-FDMA (Single Carrier Frequency Division Multiplexing) in uplink (UL) Access) method is used. Uplink refers to a radio link in which a terminal (UE (User Equipment) or MS (Mobile Station)) transmits data or control signals to a base station (eNode B or base station (BS)), and downlink refers to a radio link in which a base station transmits data or a control signal to a terminal. A radio link that transmits data or control signals. The multiple access scheme as described above can distinguish data or control information of each user by allocating and operating time-frequency resources to carry data or control information for each user so that they do not overlap each other, that is, so that orthogonality is established. can

As a future communication system after LTE, that is, a 5G communication system, since it should be able to freely reflect various requirements such as users and service providers, a service that satisfies various requirements at the same time 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

eMBB aims to provide a data transmission rate that is more improved than that supported by existing LTE, LTE-A or LTE-Pro. For example, in a 5G communication system, an eMBB must be able to provide a peak data rate of 20 Gbps in downlink and a peak data rate of 10 Gbps in uplink from the perspective of one base station. In addition, the 5G communication system should provide a maximum transmission rate and, at the same time, an increased user perceived data rate of the terminal. In order to satisfy these requirements, improvements in various transmission and reception technologies including a more advanced multi-input multi-output (MIMO) transmission technology are required. In addition, while signals are transmitted using a maximum 20MHz transmission bandwidth in the 2GHz band used by LTE, the 5G communication system uses a frequency bandwidth wider than 20MHz in a frequency band of 3 to 6GHz or 6GHz or higher, thereby providing data required by the 5G communication system. transmission speed can be satisfied.

At the same time, mMTC is being considered to support application services such as Internet of Things (IoT) in 5G communication systems. In order to efficiently provide the Internet of Things, mMTC requires access support for large-scale terminals within a cell, improved coverage of terminals, improved battery time, 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) in a cell. In addition, since a terminal supporting mMTC is likely to be located in a shadow area that is not covered by a cell, such as the basement of a building due to the nature of the service, it may require a wider coverage than other services provided by the 5G communication system. A terminal supporting mMTC must be composed of a low-cost terminal, and since it is difficult to frequently replace a 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 of robots or machinery, industrial automation, unmaned aerial vehicles, remote health care, emergency situations A service used for emergency alert or the like may be considered. Therefore, the communication provided by URLLC must provide very low latency and very high reliability. For example, a service supporting URLLC needs to satisfy an air interface latency of less than 0.5 milliseconds, and at the same time has a requirement of a packet error rate of 10 ^-5 or less. Therefore, for a service that supports URLLC, a 5G system must provide a smaller transmit time interval (TTI) than other services, and at the same time, a design that allocates wide resources in the frequency band to secure the reliability of the communication link. items may be requested.

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

[NR time-frequency resource]

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

1 is a diagram showing the basic structure of a time-frequency domain, which is a radio resource domain in which data or control channels are transmitted in a 5G system.

(일례로 12)개의 연속된 RE들은 하나의 자원 블록(Resource Block, RB, 104)을 구성할 수 있다. 1, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time and frequency domains is a resource element (RE, 101), which is defined as 1 Orthogonal Frequency Division Multiplexing (OFDM) symbol 102 in the time axis and 1 subcarrier 103 in the frequency axis. It can be. in the frequency domain

(For example, 12) consecutive REs may constitute one resource block (Resource Block, RB, 104).

2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to an embodiment of the present disclosure.

)=14). 1 서브프레임(201)은 하나 또는 복수 개의 슬롯(202, 203)으로 구성될 수 있으며, 1 서브프레임(201)당 슬롯(202, 203)의 개수는 부반송파 간격에 대한 설정 값 μ(204, 205)에 따라 다를 수 있다. 도 2의 일 예에서는 부반송파 간격 설정 값으로 μ=0(204)인 경우와 μ=1(205)인 경우가 도시되어 있다. μ=0(204)일 경우, 1 서브프레임(201)은 1개의 슬롯(202)으로 구성될 수 있고, μ=1(205)일 경우, 1 서브프레임(201)은 2개의 슬롯(203)으로 구성될 수 있다. 즉 부반송파 간격에 대한 설정 값 μ에 따라 1 서브프레임 당 슬롯 수(

)가 달라질 수 있고, 이에 따라 1 프레임 당 슬롯 수(

)가 달라질 수 있다. 각 부반송파 간격 설정 μ에 따른

및

는 하기의 표 1로 정의될 수 있다.2 shows an example of the structure of a frame (Frame, 200), a subframe (Subframe, 201), and a slot (Slot, 202). One frame 200 may be defined as 10 ms. One subframe 201 may be defined as 1 ms, and therefore, one frame 200 may consist of a total of 10 subframes 201 . One slot (202, 203) may be defined as 14 OFDM symbols (that is, the number of symbols per slot (

)=14). One subframe 201 may consist of one or a plurality of slots 202 and 203, and the number of slots 202 and 203 per one subframe 201 is a set value for the subcarrier interval μ(204, 205 ) may vary. In an example of FIG. 2 , a case where μ=0 (204) and a case where μ=1 (205) are shown as the subcarrier interval setting value. When μ = 0 (204), 1 subframe 201 may consist of one slot 202, and when μ = 1 (205), 1 subframe 201 may consist of two slots 203 may consist of That is, the number of slots per 1 subframe according to the setting value μ for the subcarrier interval (

) may vary, and accordingly, the number of slots per frame (

) may vary. According to each subcarrier spacing setting μ

and

Can be defined in Table 1 below.

0 14 10 One One 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16 5 14 320 32

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

3 is a diagram illustrating an example of setting a bandwidth portion in a wireless communication system according to an embodiment of the present disclosure.

3 shows an example in which the UE bandwidth 300 is set to two bandwidth parts, that is, bandwidth part # 1 (BWP # 1) 301 and bandwidth part # 2 (BWP # 2) 302. show The base station may set one or a plurality of bandwidth parts to the terminal, and may set the following information for each bandwidth part.

BWP ::= SEQUENCE {
bwp-Id BWP-Id,
(Bandwidth Part Identifier)
locationAndBandwidth INTEGER (1..65536),
(Bandwidth part position)
subcarrierSpacing ENUMERATED {n0, n1, n2, n3, n4, n5},
(subcarrier spacing)
cyclicPrefix ENUMERATED { extended }
(cyclic prefix)
}

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

According to some embodiments, a terminal before RRC (Radio Resource Control) connection may receive an initial bandwidth portion (Initial BWP) for initial access from a base station through a Master Information Block (MIB). More specifically, in the initial access step, the terminal receives system information (remaining system information; RMSI or System Information Block 1; may correspond to SIB1) necessary for initial access through the MIB. PDCCH for receiving can be transmitted Setting information on a control resource set (CORESET) and a search space may be received. The control area and search space set by MIB can be regarded as identity (ID) 0, respectively. The base station may notify the terminal of setting information such as frequency allocation information, time allocation information, and numerology for the control region #0 through the MIB. In addition, the base station may notify the terminal of configuration information about the monitoring period and occasion for control region #0, that is, configuration information about search space #0, through the MIB. The terminal may regard the frequency domain set as the control domain #0 acquired from the MIB as an initial bandwidth part for initial access. At this time, the identifier (ID) of the initial bandwidth part may be regarded as 0.

The setting for the portion of the bandwidth supported by 5G can be used for various purposes.

According to some embodiments, when the bandwidth supported by the terminal is smaller than the system bandwidth, it can be supported through the bandwidth portion setting. For example, the base station can transmit and receive data at a specific frequency position within the system bandwidth by setting the frequency position (configuration information 2) of the bandwidth part to the terminal.

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 spacing of 15 kHz and a subcarrier spacing of 30 kHz to a terminal, two bandwidth parts may be set to subcarrier spacings of 15 kHz and 30 kHz, respectively. Different bandwidth parts may be frequency division multiplexed, and when data is to be transmitted/received at a specific subcarrier interval, a bandwidth portion set at a corresponding subcarrier interval may be activated.

Also, according to some embodiments, for the purpose of reducing the power consumption of the terminal, the base station may set bandwidth parts having different sizes of bandwidth to the terminal. For example, when a terminal supports a very large bandwidth, for example, a bandwidth of 100 MHz and always transmits and receives data with 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 non-traffic situation 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, for example, a bandwidth part of 20 MHz for the terminal. In a situation where there is no traffic, the terminal can perform a monitoring operation in the 20 MHz bandwidth part, and when data is generated, it can transmit and receive data in the 100 MHz bandwidth part according to the instructions of the base station.

In the method for setting the bandwidth part, terminals before RRC connection (Connected) can receive setting information on the initial bandwidth part (Initial Bandwidth Part) through a Master Information Block (MIB) in an initial access step. More specifically, the terminal is a control region (Control Resource Set, CORESET) can be set. The bandwidth of the control region set by the MIB may be regarded as an initial bandwidth portion, and the UE may receive a physical downlink shared channel (PDSCH) through which the SIB is transmitted through the initial bandwidth portion set. The initial bandwidth portion may be used for other system information (Other System Information, OSI), paging, and random access in addition to the purpose of receiving the SIB.

[Change bandwidth part (BWP)]

When one or more bandwidth parts are configured for the terminal, the base station may instruct the terminal to change (or switch, transition) the bandwidth part using a bandwidth part indicator field in the DCI. For example, in FIG. 3, when the currently active bandwidth part of the terminal is bandwidth part #1 301, the base station may instruct the terminal with the bandwidth part #2 302 as a bandwidth part indicator in the DCI, and the terminal receives The bandwidth part change can be performed with the bandwidth part #2 302 indicated by the bandwidth part indicator in the DCI.

As described above, since the DCI-based bandwidth part change can be indicated by the DCI that schedules the PDSCH or PUSCH, when the UE receives the bandwidth part change request, the PDSCH or PUSCH scheduled by the corresponding DCI is grouped in the changed bandwidth part. It must be possible to receive or transmit without To this end, the standard stipulates a requirement for a delay time (T _BWP ) required when changing a bandwidth part, and may be defined, for example, as follows.

NR Slot length (ms) BWP switch delay T _BWP (slots) Type 1 ^{Note 1} Type 2 ^{Note 1} 0 One One 3 One 0.5 2 5 2 0.25 3 9 3 0.125 6 18 Note 1: Depends on UE capability.
Note 2: If the BWP switch involves changing of SCS, the BWP switch delay is determined by the larger one between the SCS before BWP switch and the SCS after BWP switch.

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 partial delay time type to the base station.

According to the above-mentioned requirement for the bandwidth portion change delay time, when the terminal receives the DCI including the bandwidth portion change indicator in slot n, the terminal changes to the new bandwidth portion indicated by the bandwidth portion change indicator in slot n+ It can be completed at a time no later than T _BWP , and transmission and reception for a data channel scheduled by the corresponding DCI can be performed in the changed new bandwidth part. When the base station wants to schedule the data channel with a new bandwidth part, it can determine the time domain resource allocation for the data channel in consideration of the bandwidth part change delay time (T _BWP ) of the terminal. That is, when scheduling a data channel with a new bandwidth part, in the method of determining time domain resource allocation for the data channel, the base station may schedule the corresponding data channel after the bandwidth part change delay time. Accordingly, the terminal may not expect that the DCI indicating the bandwidth portion change indicates a slot offset value (K0 or K2) smaller than the bandwidth portion change delay time (T _BWP ).

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

[SS/PBCH block]

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

The SS/PBCH block may refer to a physical layer channel block composed of a Primary SS (PSS), a Secondary SS (SSS), and a PBCH. Specifically, it is as follows.

- PSS: This is a signal that is a standard for downlink time/frequency synchronization and provides some information of cell ID.

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

- PBCH: Provides essential system information necessary for transmitting and receiving the data channel and control channel of the terminal. Essential system information may include search space-related control information indicating radio resource mapping information of a control channel, scheduling control information for a separate data channel through which system information is transmitted, 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 SS/PBCH block to be transmitted may be distinguished by an index.

The UE can detect the PSS and SSS in the initial access stage and decode the PBCH. The MIB can be obtained from the PBCH, and a control resource set (CORESET) #0 (which may correspond to a control region having a control region index of 0) can be set therefrom. The UE may perform monitoring for control region #0, assuming that the selected SS/PBCH block and demodulation reference signal (DMRS) transmitted in control region #0 are quasi co-located (QCL). The terminal may receive system information through downlink control information transmitted in control region #0. The terminal may obtain RACH (Random Access Channel) related setting information required for initial access from the received system information. The terminal 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 terminal. The base station can know that the terminal has selected a certain block among the SS/PBCH blocks and monitors the control region #0 related thereto.

[DRX]

6 is a diagram for explaining DRX (Discontinuous Reception).

Discontinuous Reception (DRX) is an operation in which a terminal using a service discontinuously receives data in an RRC Connected state in which a radio link is established between a base station and a terminal. When DRX is applied, the terminal can turn on the receiver at a specific time point to monitor the control channel, and turn off the receiver when there is no data received for a certain period of time to reduce power consumption of the terminal. DRX operation can be controlled by the MAC layer device based on various parameters and timers.

Referring to FIG. 6, Active time 605 is the time when the UE wakes up every DRX cycle and monitors the PDCCH. Active time 605 can be defined as follows.

- drx-onDurationTimer or drx-InactivityTimer or drx-RetransmissionTimerDL or drx-RetransmissionTimerUL or ra-ContentionResolutionTimer is running; or

- a Scheduling Request is sent on PUCCH and is pending; or

- a PDCCH indicating a new transmission addressed to the C-RNTI of the MAC entity has not been received after successful reception of a Random Access Response for the Random Access Preamble not selected by the MAC entity among the contention-based Random Access Preamble

drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, drx-RetransmissionTimerUL, ra-ContentionResolutionTimer, etc. are timers whose values are set by the base station. Have.

drx-onDurationTimer (615) is a parameter for setting the minimum time the UE is awake in the DRX cycle. The drx-InactivityTimer 620 is a parameter for setting an additional awake time when a PDCCH indicating a new uplink transmission or downlink transmission is received (630). drx-RetransmissionTimerDL is a parameter for setting the maximum awake time of a UE to receive a downlink retransmission in a downlink HARQ procedure. drx-RetransmissionTimerUL is a parameter for setting the maximum time during which the UE is awake to receive an uplink retransmission grant in an uplink HARQ procedure. drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, and drx-RetransmissionTimerUL may be set to, for example, time, the number of subframes, and the number of slots. ra-ContentionResolutionTimer is a parameter for monitoring PDCCH in a random access procedure.

InActive time 610 is a time set not to monitor PDCCH or/or not to receive PDCCH during DRX operation. (610) can be. If the terminal does not monitor the PDCCH during the active time 605, it can reduce power consumption by entering a sleep or inactive state.

The DRX cycle means a period in which the UE wakes up and monitors the PDCCH. That is, it means a time interval or an on-duration occurrence period until the UE monitors the next PDCCH after monitoring the PDCCH. There are two types of DRX cycle: short DRX cycle and long DRX cycle. Short DRX cycle can be applied as an option.

Long DRX cycle 625 is a long cycle among two DRX cycles set in the terminal. While operating in Long DRX, the terminal starts drx-onDurationTimer (615) again at the time when as much as Long DRX cycle (625) has elapsed from the start point (eg, start symbol) of drx-onDurationTimer (615). In the case of operating in a long DRX cycle 625, the terminal may start drx-onDurationTimer 615 in a slot after drx-SlotOffset in a subframe satisfying Equation 1 below. Here, drx-SlotOffset means a delay before starting drx-onDurationTimer 615. drx-SlotOffset may be set to, for example, time, number of slots, and the like.

[Equation 1]

[(SFN X 10) + subframe number] modulo (drx-LongCycle) = drx-StartOffset

At this time, drx-LongCycleStartOffset may be used to define a Long DRX cycle (625) and drx-StartOffset to define a subframe from which the Long DRX cycle (625) starts. drx-LongCycleStartOffset may be set to, for example, time, number of subframes, number of slots, and the like.

[PDCCH: DCI related]

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

Scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) in the 5G system is provided through DCI It is transmitted from the base station to the terminal. The UE may monitor the DCI format for fallback and the DCI format for non-fallback with respect to PUSCH or PDSCH. The contingency DCI format may be composed of a fixed field predefined between the base station and the terminal, and the non-preparation DCI format may include a configurable field.

DCI may be transmitted through a physical downlink control channel (PDCCH) through channel coding and modulation processes. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC may be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs may be used according to the purpose of the DCI message, eg, UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly but is included in the CRC calculation process and transmitted. Upon receiving the DCI message transmitted on the PDCCH, the UE checks the CRC using the allocated 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 a PDSCH for system information (SI) may be scrambled with SI-RNTI. A DCI scheduling a PDSCH for a Random Access Response (RAR) message may be scrambled with RA-RNTI. A 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 TPC (Transmit Power Control) can be scrambled with TPC-RNTI. DCI scheduling UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

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

] bits
- Time domain resource assignment (시간 도메인 자원 할당) - X bits
- Frequency hopping flag (주파수 호핑 플래그) - 1 bit.
- Modulation and coding scheme (변조 및 코딩 스킴) - 5 bits
- New data indicator (새로운 데이터 지시자) - 1 bit
- Redundancy version (리던던시 버전) - 2 bits
- HARQ process number (HARQ 프로세스 번호) - 4 bits
- TPC command for scheduled PUSCH (스케줄링된 PUSCH를 위한 전송 전력 제어(transmit power control) 명령 - [2] bits
- UL/SUL indicator (상향링크/추가적 상향링크(supplementary UL) 지시자) - 0 or 1 bit - Identifier for DCI formats - [1] bit
- Frequency domain resource assignment (frequency domain resource assignment) -[

] bits
- Time domain resource assignment - X bits
- Frequency hopping flag (Frequency hopping flag) - 1 bit.
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
- HARQ process number (HARQ process number) - 4 bits
- TPC command for scheduled PUSCH (transmit power control command for scheduled PUSCH - [2] bits
- UL/SUL indicator (uplink/supplementary UL indicator) - 0 or 1 bit

DCI format 0_1 can be used as a non-backup DCI for scheduling PUSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 0_1 in which CRC is scrambled with C-RNTI may include, for example, the following information.

DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 1_0 in which CRC is scrambled with C-RNTI may include, for example, the following information.

] bits
- Time domain resource assignment - X bits
- VRB-to-PRB mapping - 1 bit.
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
- HARQ process number - 4 bits
- Downlink assignment index - 2 bits
- TPC command for scheduled PUCCH - [2] bits
- PUCCH resource indicator (물리 상향링크 제어 채널(physical uplink control channel, PUCCH) 자원 지시자- 3 bits
- PDSCH-to-HARQ feedback timing indicator (PDSCH-to-HARQ 피드백 타이밍 지시자)- [3] bits- Identifier for DCI formats - [1] bit
- Frequency domain resource assignment -[

] bits
- Time domain resource assignment - X bits
- VRB-to-PRB mapping - 1 bit.
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
- HARQ process number - 4 bits
- Downlink assignment index - 2 bits
- TPC command for scheduled PUCCH - [2] bits
-PUCCH resource indicator (physical uplink control channel (PUCCH) resource indicator- 3 bits
- PDSCH-to-HARQ feedback timing indicator (PDSCH-to-HARQ feedback timing indicator)- [3] bits

DCI format 1_1 can be used as a non-backup DCI for scheduling PDSCH, and in this case, CRC can be scrambled with C-RNTI. DCI format 1_1 in which CRC is scrambled with C-RNTI may include, for example, the following information.

For resource allocation type 0,

bits

For resource allocation type 1,

bits
- Time domain resource assignment -1, 2, 3, or 4 bits
- VRB-to-PRB mapping - 0 or 1 bit, only for resource allocation type 1.

0 bit if only resource allocation type 0 is configured;

1 bit otherwise.
- PRB bundling size indicator (물리 자원 블록 번들링 크기 지시자) - 0 or 1 bit
- Rate matching indicator (레이트 매칭 지시자) - 0, 1, or 2 bits
- ZP CSI-RS trigger (영전력 채널 상태 정보 기준 신호 트리거) - 0, 1, or 2 bits
For transport block 1(제1 전송 블록의 경우):
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
For transport block 2(제2 전송 블록의 경우):
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
- HARQ process number - 4 bits
- Downlink assignment index - 0 or 2 or 4 bits
- TPC command for scheduled PUCCH - 2 bits
- PUCCH resource indicator - 3 bits
- PDSCH-to-HARQ_feedback timing indicator - 3 bits
- Antenna ports - 4, 5 or 6 bits
- Transmission configuration indication (전송 설정 지시)- 0 or 3 bits
- SRS request - 2 bits
- CBG transmission information - 0, 2, 4, 6, or 8 bits
- CBG flushing out information (코드 블록 그룹 플러싱 아웃 정보) - 0 or 1 bit
- DMRS sequence initialization - 1 bit- Carrier indicator - 0 or 3 bits
- Identifier for DCI formats - [1] bits
- Bandwidth part indicator - 0, 1 or 2 bits
- Frequency domain resource assignment

For resource allocation type 0,

bits

For resource allocation type 1,

bits
- Time domain resource assignment -1, 2, 3, or 4 bits
- VRB-to-PRB mapping - 0 or 1 bit, only for resource allocation type 1.

0 bit if only resource allocation type 0 is configured;

1 bit otherwise.
- PRB bundling size indicator (physical resource block bundling size indicator) - 0 or 1 bit
- Rate matching indicator - 0, 1, or 2 bits
- ZP CSI-RS trigger (zero power channel state information reference signal trigger) - 0, 1, or 2 bits
For transport block 1 (for the first transport block):
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
For transport block 2 (for the second transport block):
- Modulation and coding scheme - 5 bits
- New data indicator - 1 bit
- Redundancy version - 2 bits
- HARQ process number - 4 bits
- Downlink assignment index - 0 or 2 or 4 bits
- TPC command for scheduled PUCCH - 2 bits
- PUCCH resource indicator - 3 bits
- PDSCH-to-HARQ_feedback timing indicator - 3 bits
- Antenna ports - 4, 5 or 6 bits
- Transmission configuration indication - 0 or 3 bits
- SRS request - 2 bits
- CBG transmission information - 0, 2, 4, 6, or 8 bits
- CBG flushing out information (code block group flushing out information) - 0 or 1 bit
- DMRS sequence initialization - 1 bit

[PDCCH: CORESET, REG, CCE, Search Space] In the following, a downlink control channel in a 5G communication system will be described in more detail with reference to the drawings.

4 is a diagram showing an example of a control region (Control Resource Set, CORESET) in which a downlink control channel is transmitted in a 5G wireless communication system. 4 shows a UE bandwidth part 410 on the frequency axis and two control regions (control region # 1 401 and control region # 2 402) within 1 slot 420 on the time axis. Shows an example of what has been done. The control regions 401 and 402 may be set to a specific frequency resource 403 within the entire terminal bandwidth portion 410 on the frequency axis. The time axis may be set to one or a plurality of OFDM symbols, and this may be defined as a control region length (Control Resource Set Duration, 404). Referring to the illustrated example of FIG. 4 , control region #1 (401) is set to a control region length of 2 symbols, and control region #2 (402) is set to a control region length of 1 symbol.

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

ControlResourceSet ::= SEQUENCE {
-- Corresponds to L1 parameter 'CORESET-ID'

controlResourceSetId ControlResourceSetId,
(control area identifier (Identity))
frequencyDomainResources BIT STRING (SIZE (45)),
(frequency axis resource allocation information)
duration INTEGER (1..maxCoReSetDuration),
(time axis resource allocation information)
cce-REG-MappingType CHOICE {
(CCE-to-REG mapping method)
interleaved SEQUENCE {

reg-BundleSize ENUMERATED {n2, n3, n6},
(REG bundle size)

precoderGranularity ENUMERATED {sameAsREG-bundle, allContiguousRBs},

interleaverSize ENUMERATED {n2, n3, n6}
(interleaver size)

shiftIndex INTEGER(0..maxNrofPhysicalResourceBlocks-1) OPTIONAL
(Interleaver Shift)
},
nonInterleaved NULL
},
tci-StatesPDCCH SEQUENCE(SIZE (1..maxNrofTCI-StatesPDCCH)) OF TCI-StateId OPTIONAL,
(QCL setting information)
tci-PresentInDCI ENUMERATED {enabled} OPTIONAL, -- Need S
}

In Table 8, tci-StatesPDCCH (simply named TCI (Transmission Configuration Indication) state) configuration information is one or a plurality of SS (Synchronization Signal) in a Quasi Co Located (QCL) relationship with DMRS transmitted in the corresponding control area /PBCH (Physical Broadcast Channel) block index or CSI-RS (Channel State Information Reference Signal) index information may be included.

5A is a diagram showing an example of basic units of time and frequency resources constituting a downlink control channel that can be used in 5G. According to FIG. 5A, a basic unit of time and frequency resources constituting a control channel can be referred to as a REG (Resource Element Group, 503), and the REG 503 is 1 OFDM symbol 501 on the time axis and 1 PRB on the frequency axis. (Physical Resource Block, 502), that is, it can be defined as 12 subcarriers. The base station may configure a downlink control channel allocation unit by concatenating the REGs 503.

As shown in FIG. 5A, when a basic unit to which a downlink control channel is allocated in 5G is a Control Channel Element (CCE) 504, one CCE 504 may be composed of a plurality of REGs 503. Taking the REG 503 shown in FIG. 5A as an example, the REG 503 may consist of 12 REs, and if 1 CCE 504 consists of 6 REGs 503, 1 CCE 504 may consist of 72 REs. When a downlink control region is set, the corresponding region can be composed of a plurality of CCEs 504, and a specific downlink control channel is divided into one or a plurality of CCEs 504 according to an aggregation level (AL) in the control region. It can be mapped and transmitted. The CCEs 504 in the control area are identified by numbers, and at this time, the numbers of the CCEs 504 may be assigned according to a logical mapping method.

The basic unit of the downlink control channel, that is, the REG 503 shown in FIG. 5A, may include both REs to which DCI is mapped and a region to which the DMRS 505, which is a reference signal for decoding them, is mapped. As shown in FIG. 5A, three DMRSs 505 may be transmitted within one REG 503. The number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16 according to the aggregation level (AL), and the different numbers of CCEs can be used for link adaptation of the downlink control channel. can be used to implement For example, when AL=L, one downlink control channel can be transmitted through L CCEs. A UE needs to detect a signal without knowing information about a downlink control channel. A search space representing a set of CCEs is defined for blind decoding. 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 group with 1, 2, 4, 8, and 16 CCEs Since there are levels, the terminal can have a plurality of search spaces. A search space set may be defined as a set of search spaces at all set aggregation levels.

The search space can be classified into a common search space and a UE-specific search space. A certain group of terminals or all terminals can search the common search space of the PDCCH in order to receive cell-common control information such as dynamic scheduling for system information or a paging message. For example, PDSCH scheduling allocation information for SIB transmission including cell operator information may be received by examining the common search space of the PDCCH. In the case of a common search space, since a certain group of terminals or all terminals must receive the PDCCH, it can be defined as a set of pre-promised CCEs. Scheduling assignment information for the UE-specific PDSCH or PUSCH may be received by examining the UE-specific search space of the PDCCH. The UE-specific search space may be defined UE-specifically as a function of the identity of the UE and various system parameters.

In 5G, a parameter for a search space for a PDCCH may be configured from a base station to a terminal through higher layer signaling (eg, SIB, MIB, RRC signaling). For example, the base station includes the number of PDCCH candidate groups at each aggregation level L, a monitoring period for the search space, a monitoring occasion in symbol units within a slot for the search space, a search space type (common search space or UE-specific search space), A combination of a DCI format and an RNTI to be monitored in the corresponding search space, a control region index to be monitored in the search space, and the like may be set to the terminal. For example, it may include the following information.

According to the setting information, the base station may set one or a plurality of search space sets for the terminal. According to some embodiments, the base station may set search space set 1 and search space set 2 to the terminal, set DCI format A scrambled with X-RNTI in search space set 1 to be monitored in a common search space, and search DCI format B scrambled with Y-RNTI in space set 2 can be configured to be monitored in the UE-specific search space. According to the configuration information, one or a plurality of search space sets exist in the common search space or the UE-specific search space. can For example, search space set #1 and search space set #2 may be set as common search spaces, and search space set #3 and search space set #4 may be set as terminal-specific search spaces.

In the common search space, a combination of the following DCI format and RNTI can 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 following definitions and uses.

C-RNTI (Cell RNTI): Use of UE-specific PDSCH scheduling

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

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

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

P-RNTI (Paging RNTI): PDSCH scheduling purpose through which paging is transmitted

SI-RNTI (System Information RNTI): PDSCH scheduling purpose for transmitting system information

INT-RNTI (Interruption RNTI): used to inform whether pucturing for PDSCH

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

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

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

The aforementioned specified DCI formats may follow the definition below.

DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1 Scheduling of PUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1 Scheduling of PDSCH in one cell 2_0 Notifying a group of UEs of the slot format 2_1 Notifying a group of UEs of the PRB(s) and OFDM symbol(s) where UE may assume no transmission is intended for the UE 2_2 Transmission of TPC commands for PUCCH and PUSCH 2_3 Transmission of a group of TPC commands for SRS transmissions by one or more UEs

In 5G, the search space of the aggregation level L in the control region p and the search space set s can be expressed as Equation 2 below.

[Equation 2]

- L: aggregation level

: 캐리어(Carrier) 인덱스-

: Carrier index

: 제어영역 p 내에 존재하는 총 CCE 개수-

: Total number of CCEs present in the control area p

: 슬롯 인덱스-

: slot index

: 집성 레벨 L의 PDCCH 후보군 수-

: Number of PDCCH candidates at aggregation level L

= 0, ...,

-1: 집성 레벨 L의 PDCCH 후보군 인덱스-

= 0, ...,

-1: PDCCH candidate group index of aggregation level L

= 0, ..., L -1-

= 0, ..., L -1

,

,

,

,

,

-

,

,

,

,

,

: 단말 식별자-

: terminal identifier

값은 공통 탐색공간의 경우 0에 해당할 수 있다.

The value may correspond to 0 in the case of a common search space.

값은 단말-특정 탐색공간의 경우, 단말의 신원(C-RNTI 또는 기지국이 단말에게 설정해준 ID)과 시간 인덱스에 따라 변하는 값에 해당할 수 있다.

In the case of a UE-specific search space, the value may correspond to a value that changes according to the identity of the UE (C-RNTI or ID set for the UE by the base station) and the time index.

In 5G, as a plurality of search space sets can be set with different parameters (eg, parameters in Table 9), the set of search space sets monitored by the terminal at each point in time may be different. For example, if search space set #1 is set to an X-slot period and search space set #2 is set to a Y-slot period and X and Y are different, the terminal searches search space set #1 and search space set #1 in a specific slot. All space set #2 can be monitored, and one of search space set #1 and search space set #2 can be monitored in a specific slot.

[PDCCH: span]

The terminal may perform a terminal capability report for the case of having a plurality of PDCCH monitoring positions within a slot for each subcarrier interval, and in this case, the concept of span may be used. A span means consecutive symbols in which a terminal can monitor a PDCCH within a slot, and each PDCCH monitoring position is within one span. A span can be expressed as (X,Y), where x means the minimum number of symbols that must be separated between the first symbols of two consecutive spans, and Y is the number of consecutive symbols that can monitor the PDCCH within one span. says At this time, the UE can monitor the PDCCH in a section within Y symbols from the first symbol of Span within Span.

5B is a diagram illustrating a case in which a terminal can have a plurality of PDCCH monitoring positions in a slot in a wireless communication system through Span. Span can be (X,Y) = (7,3), (4,3), (2,2), and each of the three cases is (5-1-00), (5-1-05) in FIG. ), (5-1-10). As an example, (5-1-00) expresses the case where there are two spans in a slot that can be expressed as (7,4). The interval between the first symbols of two spans is expressed as X=7, PDCCH monitoring positions can exist within a total of Y=3 symbols from the first symbol of each span, and search spaces 1 and 2 within Y=3 symbols indicated the presence of each. As another example, in (5-1-05), a case where a total of three spans exist in a slot that can be expressed as (4,3) is expressed, and the interval between the second and third spans is greater than X=4. Indicated that the big X'=5 symbols away.

[PDCCH: UE Capability Report]

Slot positions in which the above-described common search space and the terminal-specific search space are located are indicated by the monitoringSymbolsWitninSlot parameter in Table 11, and symbol positions in slots are indicated as a bitmap through the monitoringSymbolsWithinSlot parameter in Table 9. Meanwhile, a symbol position within a slot in which search space monitoring is possible by the terminal may be reported to the base station through the following UE capabilities.

- Terminal capability 1 (hereinafter referred to as FG 3-1). As shown in Table 9a below, when there is one MO monitoring occasion (MO) for the type 1 and type 3 common search space or the UE-specific search space in the slot, the corresponding MO location is the first in the slot, as shown in Table 9a below. When located within 3 symbols, it means the ability to monitor the corresponding MO. This UE capability is a mandatory capability that all UEs supporting NR must support, and whether or not this capability is supported is not explicitly reported to the base station.

Index Feature group Components Field name in TS 38.331 [2] 3-1 Basic DL control channel 1) One configured CORESET per BWP per cell in addition to CORESET0- CORESET resource allocation of 6RB bit-map and duration of 1 - 3 OFDM symbols for FR1
- For type 1 CSS without dedicated RRC configuration and for type 0, 0A, and 2 CSSs, CORESET resource allocation of 6RB bit-map and duration 1-3 OFDM symbols for FR2
- For type 1 CSS with dedicated RRC configuration and for type 3 CSS, UE specific SS, CORESET resource allocation of 6RB bit-map and duration 1-2 OFDM symbols for FR2
- REG-bundle sizes of 2/3 RBs or 6 RBs
- Interleaved and non-interleaved CCE-to-REG mapping
- Precoder-granularity of REG-bundle size
- PDCCH DMRS scrambling determination
- TCI state(s) for a CORESET configuration
2) CSS and UE-SS configurations for unicast PDCCH transmission per BWP per cell
- PDCCH aggregation levels 1, 2, 4, 8, 16
- UP to 3 search space sets in a slot for a scheduled SCell per BWP
This search space limit is before applying all dropping rules.
- For type 1 CSS with dedicated RRC configuration, type 3 CSS, and UE-SS, the monitoring occasion is within the first 3 OFDM symbols of a slot
- For type 1 CSS without dedicated RRC configuration and for type 0, 0A, and 2 CSS, the monitoring occasion can be any OFDM symbol(s) of a slot, with the monitoring occasions for any of Type 1- CSS without dedicated RRC configuration , or Types 0, 0A, or 2 CSS configurations within a single span of three consecutive OFDM symbols within a slot
3) Monitoring DCI formats 0_0, 1_0, 0_1, 1_1
4) Number of PDCCH blind decodes per slot with a given SCS follows Case 1-1 table
5) Processing one unicast DCI scheduling DL and one unicast DCI scheduling UL per slot per scheduled CC for FDD
6) Processing one unicast DCI scheduling DL and 2 unicast DCI scheduling UL per slot per scheduled CC for TDD n/a

- Terminal capability 2 (hereafter referred to as FG 3-2). As shown in Table 12 below, when there is one monitoring occasion (MO) in a slot for a common search space or a UE-specific search space, monitoring is possible regardless of the start symbol position of the MO. means competence. This terminal capability can be selectively supported by the terminal (optional), and whether or not this capability is supported is explicitly reported to the base station.

Index Feature group Components Field name in TS 38.331 [2] 3-2 PDCCH monitoring on any span of up to 3 consecutive OFDM symbols of a slot For a given UE, all search space configurations are within the same span of 3 consecutive OFDM symbols in the slot pdcchMonitoringSingleOccasion

- Terminal capability 3 (hereafter referred to as FGs 3-5, 3-5a, 3-5b). As shown in Table 13 below, the UE capability indicates a pattern of MOs that can be monitored by the UE when a plurality of monitoring occasions (MOs) for a common search space or a UE-specific search space exist in a slot. The above-described pattern consists of a starting inter-symbol interval X between different MOs and a maximum symbol length Y for one MO. The combination of (X,Y) supported by the terminal may be one or a plurality of {(2,2), (4,3), (7,3)}. This terminal capability can be selectively supported by the terminal (optional), and whether or not this capability is supported and the above-described (X,Y) combination are explicitly reported to the base station.

Index Feature group Components Field name in TS 38.331 [2] 3-5 For type 1 CSS with dedicated RRC configuration, type 3 CSS, and UE-SS, monitoring occasion can be any OFDM symbol(s) of a slot for Case 2 For type 1 CSS with dedicated RRC configuration, type 3 CSS, and UE-SS, monitoring occasion can be any OFDM symbol(s) of a slot for Case 2 pdcch-MonitoringAnyOccasions {
3-5. withoutDCI-Gap
3-5a. with DCI-Gap
} 3-5a For type 1 CSS with dedicated RRC configuration, type 3 CSS, and UE-SS, monitoring occasion can be any OFDM symbol(s) of a slot for Case 2 with a DCI gap For type 1 CSS with dedicated RRC configuration, type 3 CSS and UE-SS, monitoring occasion can be any OFDM symbol(s) of a slot for Case 2, with minimum time separation (including the cross-slot boundary case) between two DL unicast DCIs, between two UL unicast DCIs, or between a DL and an UL unicast DCI in different monitoring occasions where at least one of them is not the monitoring occasions of FG-3-1, for a same UE as
- 2OFDM symbols for 15kHz
- 4 OFDM symbols for 30kHz
- 7OFDM symbols for 60kHz with NCP
- 11 OFDM symbols for 120kHz
Up to one unicast DL DCI and up to one unicast UL DCI in a monitoring occasion except for the monitoring occasions of FG 3-1.
In addition for TDD the minimum separation between the first two UL unicast DCIs within the first 3 OFDM symbols of a slot can be zero OFDM symbols. 3-5b All PDCCH monitoring occasion can be any OFDM symbol(s) of a slot for Case 2 with a span gap PDCCH monitoring occasions of FG-3-1, plus additional PDCCH monitoring occasion(s) can be any OFDM symbol(s) of a slot for Case 2, and for any two PDCCH monitoring occasions belonging to different spans, where at least one of they are not the monitoring occasions of FG-3-1, in same or different search spaces, there is a minimum time separation of X OFDM symbols (including the cross-slot boundary case) between the start of two spans, where each span is of length up to Y consecutive OFDM symbols of a slot. Spans do not overlap. Every span is contained in a single slot. The same span pattern repeats in every slot. The separation between consecutive spans within and across slots may be unequal but the same (X, Y) limit must be satisfied by all spans. Every monitoring occasion is fully contained in one span. In order to determine a suitable span pattern, first a bitmap b(l), 0<=l<=13 is generated, where b(l)=1 if symbol l of any slot is part of a monitoring occasion, b(l )=0 otherwise. The first span in the span pattern begins at the smallest l for which b(l)=1. The next span in the span pattern begins at the smallest l not included in the previous span(s) for which b(l)=1. The span duration is max{maximum value of all CORESET durations, minimum value of Y in the UE reported candidate value} except possibly the last span in a slot which can be of shorter duration. A particular PDCCH monitoring configuration meets the UE capability limitation if the span arrangement satisfies the gap separation for at least one (X, Y) in the UE reported candidate value set in every slot, including cross slot boundary.
For the set of monitoring occasions which are within the same span:
Processing one unicast DCI scheduling DL and one unicast DCI scheduling UL per scheduled CC across this set of monitoring occasions for FDD
Processing one unicast DCI scheduling DL and two unicast DCI scheduling UL per scheduled CC across this set of monitoring occasions for TDD
·Processing two unicast DCI scheduling DL and one unicast DCI scheduling UL per scheduled CC across this set of monitoring occasions for TDD.
The number of different start symbol indices of spans for all PDCCH monitoring occasions per slot, including PDCCH monitoring occasions of FG-3-1, is no more than floor(14/X) (X is minimum among values reported by UE).
The number of different start symbol indices of PDCCH monitoring occasions per slot including PDCCH monitoring occasions of FG-3-1, is no more than 7.
The number of different start symbol indices of PDCCH monitoring occasions per half-slot including PDCCH monitoring occasions of FG-3-1 is no more than 4 in SCell.

The UE may report whether or not to support UE capability 2 and/or UE capability 3 and related parameters to the BS. The base station may perform time axis resource allocation for a common search space and a terminal-specific search space based on the reported terminal capabilities. When allocating the resource, the base station may prevent the terminal from locating the MO in a position where monitoring is impossible.

[PDCCH: BD/CCE limit]

When a plurality of search space sets are configured for a terminal, the following conditions may be considered in a method for determining a search space set to be monitored by a terminal.

If the UE has set the value of monitoringCapabilityConfig-r16, which is upper layer signaling, to r15monitoringcapability, the UE can monitor the number of PDCCH candidate groups that can be monitored and the total search space (here, the total search space is the number corresponding to the union area of a plurality of search space sets). The maximum value for the number of CCEs constituting the entire CCE set) is defined for each slot, and if the value of monitoringCapabilityConfig-r16 is set to r16monitoringcapability, the UE determines the number of PDCCH candidates that can be monitored and the total search space ( Here, the total search space means the entire set of CCEs corresponding to the union area of a plurality of search space sets). The maximum value for the number of CCEs constituting each span is defined.

[Condition 1: Limit the maximum number of PDCCH candidates]

As described above, M ^μ , the maximum number of PDCCH candidates that can be monitored by the UE according to the setting value of higher layer signaling, is defined on a slot-by-slot basis in a cell set to a subcarrier interval of 15 2 ^μ kHz, according to Table 14 below , When defined based on Span, Table 15 below may be followed.

Maximum number of PDCCH candidates per slot and per serving cell (M ^μ ) 0 44 One 36 2 22 3 20

Maximum number M ^μ of monitored PDCCH candidates per span for combination (X,Y) and per serving cell

(2,2) (4,3) (7,3) 0 14 28 44 One 12 24 36

[Condition 2: Limit the maximum number of CCEs]

As described above, C ^μ , the maximum number of CCEs constituting the entire search space (here, the entire search space means the entire set of CCEs corresponding to the union area of a plurality of search space sets) according to the setting value of higher layer signaling, is Table 16 below may be followed when defined on a slot basis in a cell set to a carrier interval of 15 2 ^μ kHz, and Table 17 below may be followed when defined on a span basis.

Maximum number of non-overlapped CCEs per slot and per serving cell (C ^μ ) 0 56 One 56 2 48 3 32

Maximum number C ^μ of non-overlapped CCEs per span for combination (X,Y) and per serving cell

(2,2) (4,3) (7,3) 0 18 36 56 One 18 36 56

For convenience of description, a situation in which both conditions 1 and 2 are satisfied at a specific point in time is defined as “condition A”. Accordingly, not satisfying condition A may mean not satisfying at least one of conditions 1 and 2 above.

[PDCCH: Overbooking]

Depending on the setting of search space sets of the base station, a case in which condition A is not satisfied may occur at a specific point in time. When condition A is not satisfied at a specific time point, the terminal may select and monitor only a part of search space sets configured to satisfy condition A at that time point, and the base station may transmit a PDCCH to the selected search space set.

As a method of selecting some search spaces from the set of all set search spaces, the following method may be followed.

If condition A for the PDCCH is not satisfied at a specific time point (slot), the UE (or the base station) selects a search space set whose search space type is set to a common search space among search space sets existing at that time point. - Priority can be given to a search space set set as a specific search space.

When all search space sets set as the common search space are selected (that is, when condition A is satisfied even after all search spaces set as the common search space are selected), the terminal (or the base station) terminal-specific search space Search space sets set to can be selected. In this case, when there are a plurality of search space sets set as the terminal-specific search space, a search space set having a lower search space set index may have a higher priority. In consideration of priority, UE-specific search space sets may be selected within a range satisfying condition A.

[QCL, TCI state]

In a wireless communication system, one or more different antenna ports (or one or more channels, signals, and combinations thereof may be substituted, but in the future description of the present disclosure, for convenience, different antenna ports are collectively referred to) They can be associated with each other by setting QCL (Quasi co-location) as shown in [Table 18] below. The TCI state is to notify the QCL relationship between a PDCCH (or PDCCH DMRS) and another RS or channel. A reference antenna port A (reference RS #A) and another target antenna port B (target RS #B) are QCL QCLed means that the terminal is allowed to apply some or all of the large-scale channel parameters estimated from the antenna port A to channel measurement from the antenna port B. QCL is 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, 4) spatial parameter It may be necessary to associate different parameters depending on circumstances such as affected beam management (BM). Accordingly, NR supports four types of QCL relationships as shown in Table 18 below.

QCL type Large-scale characteristics A Doppler shift, Doppler spread, average delay, delay spread B Doppler shift, Doppler spread C Doppler shift, average delay D Spatial Rx parameter

The spatial RX parameter includes various parameters such as Angle of arrival (AoA), Power Angular Spectrum (PAS) of AoA, Angle of departure (AoD), PAS of AoD, transmit/receive channel correlation, transmit/receive beamforming, and spatial channel correlation. Some or all of them may be generically named.

The QCL relationship can be set to the terminal through the RRC parameters TCI-State and QCL-Info as shown in Table 19 below. Referring to Table 19, 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) for the RS referring to the ID of the TCI state, that is, 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 corresponding QCL information, the type and ID of the reference RS, and the QCL type as shown in Table 18 above. do.

TCI-State ::= SEQUENCE {
tci-StateId TCI-StateId,
(ID of the TCI state)
qcl-Type1 QCL-Info;
(QCL information of the first reference RS of RS (target RS) referring to the corresponding TCI state ID)
qcl-Type2 QCL-Info OPTIONAL, -- Need R
(QCL information of the second reference RS of RS (target RS) referring to the corresponding TCI state ID)
...
}

QCL-Info ::= SEQUENCE {
cell ServCellIndex OPTIONAL, -- Need R
(The serving cell index of the reference RS indicated by the corresponding QCL information)
bwp-Id BWP-Id OPTIONAL, -- Cond CSI-RS-Indicated
(BWP index of the reference RS indicated by the corresponding QCL information)
referenceSignal CHOICE {
csi-rs NZP-CSI-RS-ResourceId,
ssb SSB-Index
(either CSI-RS ID or SSB ID indicated by the corresponding QCL information)
},
qcl-Type ENUMERATED {typeA, typeB, typeC, typeD},
...
}

7 is a diagram illustrating an example of base station beam allocation according to TCI state setting. Referring to FIG. 7 , the base station may transmit information on different N beams to the terminal through different N TCI states. For example, as shown in FIG. 7, when N = 3, the base station has qcl-Type2 parameters included in three TCI states (700, 705, and 710) associated with CSI-RS or SSB corresponding to different beams, and QCL type D By setting to , it can be notified that the antenna ports referring to the different TCI states 700, 705, or 710 are associated with different spatial Rx parameters, that is, different beams.

Tables 20 to 24 below show valid TCI state settings according to the type of target antenna port.

Table 20 shows valid TCI state settings when the target antenna port is CSI-RS for tracking (TRS). The TRS means an NZP CSI-RS in which a repetition parameter is not set and trs-Info is set to true among CSI-RSs. In the case of setting No. 3 in Table 20, it can be used for aperiodic TRS.

Table 21 shows valid TCI state settings when the target antenna port is CSI-RS for CSI. The CSI-RS for CSI refers to an NZP CSI-RS in which a parameter indicating repetition (eg, a repetition parameter) is not set and trs-Info is not set to true among CSI-RSs.

Table 22 shows valid TCI state settings when the target antenna port is CSI-RS for beam management (BM, meaning the same as CSI-RS for L1 RSRP reporting). The CSI-RS for BM means an NZP CSI-RS in which the repetition parameter is set among CSI-RSs and has a value of On or Off, and trs-Info is not set to true.

Table 23 shows valid TCI state settings when the target antenna port is PDCCH DMRS.

Table 24 shows valid TCI state settings when the target antenna port is PDSCH DMRS.

In the representative QCL setting method according to Tables 20 to 24, the target antenna port and reference antenna port for each step are "SSB" -> "TRS" -> "CSI-RS for CSI, or CSI-RS for BM, or PDCCH DMRS , or PDSCH DMRS". Through this, it is possible to help the reception operation of the terminal by linking the statistical characteristics measurable from the SSB and TRS to each antenna port.

[PDCCH: related to TCI state]

Specifically, the TCI state combinations applicable to the PDCCH DMRS antenna port are shown in Table 25 below. In Table 25, the fourth row is a combination assumed by the terminal before RRC configuration, and configuration after RRC is impossible.

Valid TCI
state Configuration DL RS 1 qcl-Type1 DL RS 2
(if configured) qcl-Type2
(if configured) One TRS QCL-TypeA TRS QCL-TypeD 2 TRS QCL-TypeA CSI-RS (BM) QCL-TypeD 3 CSI-RS (CSI) QCL-TypeA 4 SS/PBCH Block QCL-TypeA SS/PBCH Block QCL-TypeD

In NR, a hierarchical signaling method as shown in FIG. 8 is supported for dynamic allocation of PDCCH beams. Referring to FIG. 8, the base station can set N TCI states (805, 810, ..., 820) to the terminal through RRC signaling 800, and some of them can be set as TCI states for CORESET. (825). Thereafter, the base station may instruct the terminal one of TCI states (830, 835, 840) for CORESET through MAC CE signaling (845). Thereafter, the UE receives the PDCCH based on beam information included in the TCI state indicated by the MAC CE signaling.

9 is a diagram illustrating a TCI indication MAC CE signaling structure for the PDCCH DMRS. Referring to FIG. 9, the TCI indication MAC CE signaling for the PDCCH DMRS consists of 2 bytes (16 bits), 5-bit serving cell ID 915, 4-bit CORESET ID 920, and 7-bit TCI state ID 925.

10 is a diagram illustrating an example of beam configuration of a control resource set (CORESET) and a search space according to the above description. Referring to FIG. 10, the base station may indicate one of the TCI state lists included in the CORESET 1000 configuration through MAC CE signaling (1005). After that, until another TCI state is indicated to the corresponding CORESET through another MAC CE signaling, the UE uses the same QCL information (beam #1, 1005) in one or more search spaces (1010, 1015, 1020) connected to the CORESET. is considered to apply. The PDCCH beam allocation method described above makes it difficult to indicate a beam change faster than the MAC CE signaling delay, and also has the disadvantage of collectively applying the same beam for each CORESET regardless of search space characteristics, which makes flexible PDCCH beam operation difficult. there is In the following embodiments of the present invention, more flexible PDCCH beam configuration and operation methods are provided. Hereinafter, in describing the embodiments of the present invention, several distinct examples are provided for convenience of explanation, but they are not mutually exclusive and can be applied by appropriately combining with each other depending on the situation.

The base station may set one or a plurality of TCI states for a specific control region to the terminal, and may activate one of the set TCI states through a MAC CE activation command. For example, {TCI state#0, TCI state#1, TCI state#2} are set as TCI states in control region #1, and the base station sets the TCI state for control region #1 through MAC CE. A command enabling to assume #0 may be transmitted to the terminal. The terminal can correctly receive the DMRS of the corresponding control region based on the QCL information in the activated TCI state based on the activation command for the TCI state received through the MAC CE.

Regarding the control area (control area #0) whose index is set to 0, if the terminal does not receive the MAC CE activation command for the TCI state of control area #0, the terminal responds to the DMRS transmitted from the control area #0 It may be assumed that the SS/PBCH block identified in the initial access process or in the non-contention based random access process not triggered by the PDCCH command is QCL.

Regarding the control area (control area #X) where the index is set to a value other than 0, if the terminal does not set the TCI state for the control area #X or activates one of them even though one or more TCI states are set If the MAC CE activation command is not received, the terminal may assume that the SS/PBCH block identified in the initial access process is QCL with respect to the DMRS transmitted in the control region #X.

[PDCCH: related to QCL prioritization rule]

In the following, the QCL priority determination operation for the PDCCH will be described in detail.

The UE operates with carrier aggregation within a single cell or band, and a plurality of control resource sets existing within an activated bandwidth portion within a single or multiple cells have the same or different QCL-TypeD characteristics in a specific PDCCH monitoring interval and In case of overlapping, the terminal may select a specific control resource set according to the QCL priority determination operation and monitor control resource sets having the same QCL-TypeD characteristics as the corresponding control resource set. That is, when a plurality of control resource sets overlap in time, only one QCL-TypeD characteristic can be received. In this case, the criteria for determining the QCL priority may be as follows.

- Criterion 1. A control resource set connected to the common search section of the lowest index within a cell corresponding to the lowest index among cells including a common search section.

- Criterion 2. A control resource set associated with a UE-specific search interval having the lowest index within a cell corresponding to the lowest index among cells including a UE-specific search interval.

As described above, each of the above criteria applies the next criterion when the criterion is not satisfied. For example, when control resource sets overlap in time in a specific PDCCH monitoring period, if all control resource sets are not connected to a common search period but connected to a terminal-specific search period, that is, if criterion 1 is not satisfied, the terminal may omit the application of criterion 1 and apply criterion 2.

When selecting a control resource set based on the above criteria, the terminal may additionally consider the following two items for QCL information set in the control resource set. First, if control resource set 1 has CSI-RS 1 as a reference signal having a QCL-TypeD relationship, and this CSI-RS 1 has SSB 1 as a reference signal having a QCL-TypeD relationship, another If the reference signal with which control resource set 2 has a QCL-TypeD relationship is SSB 1, the UE may consider these two control resource sets 1 and 2 to have different QCL-TypeD characteristics. Second, if control resource set 1 has CSI-RS 1 set in cell 1 as a reference signal having a QCL-TypeD relationship, and this CSI-RS 1 has a QCL-TypeD relationship, the reference signal is SSB 1, control resource set 2 has CSI-RS 2 configured in cell 2 as a reference signal having a QCL-TypeD relationship, and this CSI-RS 2 has the same reference signal having a QCL-TypeD relationship. In the case of SSB 1, the UE may consider the two control resource sets to have the same QCL-TypeD characteristics.

12 is a diagram for explaining a method for selecting a receivable control resource set in consideration of priority when a terminal receives a downlink control channel in a wireless communication system according to an embodiment of the present disclosure. As an example, the terminal may be set to receive a plurality of control resource sets (CORESETs) overlapping in time in a specific PDCCH monitoring period 1210, and these plurality of control resource sets are configured for a plurality of cells. It may be connected to a common search space (CSS) or a UE-specific search space (USS). Within the corresponding PDCCH monitoring period, within the first bandwidth portion 1200 of the first cell, the first control resource set 1215 connected to the first common discovery period may exist, and the first bandwidth portion of the second cell (1205 ), the first control resource set 1220 connected to the first common search period and the second control resource set 1225 connected to the second terminal-specific search period may exist. The control resource sets 1215 and 1220 have a relationship of CSI-RS resource #1 and QCL-TypeD set within the bandwidth part #1 of cell #1, and the control resource set 1225 is the bandwidth #1 of cell #2. It may have a relationship between CSI-RS resource No. 1 set in the part and QCL-TypeD. Therefore, if criterion 1 is applied to the corresponding PDCCH monitoring period 1210, all other control resource sets having QCL-TypeD reference signals such as the first control resource set 1215 can be received. Therefore, the terminal can receive the control resource sets 1215 and 1220 in the corresponding PDCCH monitoring period 1210. As another example, the terminal may be configured to receive a plurality of control resource sets overlapping in time in a specific PDCCH monitoring period 1240, and these plurality of control resource sets are a common search space or terminal for a plurality of cells. It may be associated with a specific search space. Within the corresponding PDCCH monitoring interval, within the first bandwidth portion 1230 of cell #1, the first control resource set 1245 connected to the UE 1 specific search interval and the second control resource set connected to the UE 2 specific search interval 1250 may exist, and within the first bandwidth part 1235 of the second cell, the first control resource set 1255 connected to the first terminal-specific search period and the second control resource connected to the third terminal-specific search period A set 1260 may exist. Control resource sets 1245 and 1250 have a relationship of CSI-RS resource #1 and QCL-TypeD set within bandwidth #1 of cell #1, and control resource set 1255 is bandwidth #1 of cell #2 It has a QCL-TypeD relationship with the first CSI-RS resource set in the second cell, and the control resource set 1260 may have a QCL-TypeD relationship with the second CSI-RS resource set in the first bandwidth portion of the second cell. there is. However, when criterion 1 is applied to the corresponding PDCCH monitoring period 1240, since there is no common search period, criterion 2, which is the next criterion, can be applied. If criterion 2 is applied to the corresponding PDCCH monitoring period 1240, all other control resource sets having the same QCL-TypeD reference signal as the control resource set 1245 can be received. Therefore, the terminal can receive control resource sets 1245 and 1250 in the corresponding PDCCH monitoring period 1240.

[Related to Rate matching/Puncturing]

In the following, a rate matching operation and a puncturing operation will be described in detail.

When the time and frequency resource A to transmit a certain symbol sequence A overlaps with the random time and frequency resource B, rate matching or puncturing is performed by transmission/reception of channel A considering resource C in the area where resource A and resource B overlap motion can be considered. A specific operation may follow the following.

Rate Matching Behavior

- The base station may map and transmit channel A only for the remaining resource regions excluding resource C corresponding to an overlapping region with resource B among all resources A to transmit symbol sequence A to the terminal. For example, symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol 4}, resource A is {resource #1, resource #2, resource #3, resource #4}, resource If B is {resource #3, resource #5}, the base station excluding {resource #3} corresponding to resource C among resource A is a symbol sequence for the remaining resources {resource #1, resource #2, resource #4} A can be sequentially mapped and sent. As a result, the base station may map symbol sequences {symbol #1, symbol #2, and symbol #3} to {resource #1, resource #2, and resource #4} and transmit them.

The terminal can determine resource A and resource B from scheduling information on symbol sequence A from the base station, and through this, it can determine resource C, which is an area where resource A and resource B overlap. The UE may receive the symbol sequence A assuming that the symbol sequence A is mapped and transmitted in the remaining regions excluding resource C from among all resources A. For example, symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol 4}, resource A is {resource #1, resource #2, resource #3, resource #4}, resource If B is {resource #3, resource #5}, the terminal excluding {resource #3} corresponding to resource C among resource A is a symbol sequence for the remaining resources {resource #1, resource #2, resource #4} It can be received assuming that A is sequentially mapped. As a result, the terminal assumes that the symbol sequences {symbol #1, symbol #2, and symbol #3} are mapped to {resource #1, resource #2, and resource #4}, respectively, and performs a series of reception operations thereafter. can

Puncture operation

The base station maps the symbol sequence A to the entire resource A when there is a resource C corresponding to a region overlapping with the resource B among all resources A to transmit the symbol sequence A to the terminal, but transmits in the resource region corresponding to the resource C Transmission may be performed only for the remaining resource regions excluding resource C from among resource A without performing the transmission. For example, symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol 4}, resource A is {resource #1, resource #2, resource #3, resource #4}, resource If B is {resource #3, resource #5}, the base station converts the symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} to resource A {resource #1, resource #2, resource # 3, resource #4}, and symbol sequences corresponding to {resource #1, resource #2, resource #4}, which are the remaining resources excluding {resource #3} corresponding to resource C among resource A { Only symbol #1, symbol #2, and symbol #4} may be transmitted, and {symbol #3} mapped to {resource #3} corresponding to resource C may not be transmitted. As a result, the base station may map symbol sequences {symbol #1, symbol #2, and symbol #4} to {resource #1, resource #2, and resource #4} and transmit them.

The terminal can determine resource A and resource B from scheduling information on symbol sequence A from the base station, and through this, it can determine resource C, which is an area where resource A and resource B overlap. The terminal may receive the symbol sequence A assuming that the symbol sequence A is mapped to the entire resource A and transmitted only in the remaining regions excluding resource C among the resource regions A. For example, symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol 4}, resource A is {resource #1, resource #2, resource #3, resource #4}, resource If B is {resource #3, resource #5}, the terminal determines that the symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} is resource A {resource #1, resource #2, resource # 3 and resource #4}, but it can be assumed that {symbol #3} mapped to {resource #3} corresponding to resource C is not transmitted, and {resource #3 corresponding to resource C among resource A }, it can be received assuming that the symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to the remaining resources {resource #1, resource #2, resource #4} is mapped and transmitted. As a result, the terminal assumes that the symbol sequence {symbol #1, symbol #2, symbol #4} is mapped to {resource #1, resource #2, resource #4} and transmitted, and performs a series of subsequent reception operations. can

In the following, a method for setting rate matching resources for the purpose of rate matching in the 5G communication system will be described. Rate matching means that the size of the signal is adjusted in consideration of the amount of resources capable of transmitting the signal. For example, rate matching of a data channel may mean that the size of data is adjusted accordingly without mapping and transmitting the data channel for a specific time and frequency resource domain.

11 is a diagram for explaining a method for transmitting and receiving data between a base station and a terminal in consideration of a downlink data channel and a rate matching resource.

11 shows a downlink data channel (PDSCH) 1101 and a rate matching resource 1102. The base station may configure one or multiple rate matching resources 1102 to the terminal through higher layer signaling (eg, RRC signaling). The rate matching resource 1102 setting information may include time axis resource allocation information 1103 , frequency axis resource allocation information 1104 , and period information 1105 . In the following, the bitmap corresponding to the frequency-axis resource allocation information 1104 corresponds to the "first bitmap", the bitmap corresponding to the time-axis resource allocation information 1103 corresponds to the "second bitmap", and the period information 1105 The bitmap to be called is named "third bitmap". When all or part of the time and frequency resources of the scheduled data channel 1101 overlap with the configured rate matching resource 602, the base station rate-matches the data channel 1101 in the rate matching resource 1102 portion and transmits the , the terminal may perform reception and decoding after assuming that the data channel 1101 is rate-matched in the rate matching resource 1102 portion.

The base station may dynamically notify the terminal through DCI whether to rate match the data channel in the set rate matching resource part through additional configuration (corresponding to the "rate matching indicator" in the aforementioned DCI format) . Specifically, the base station may select some of the configured rate matching resources and group them into rate matching resource groups, and informs the terminal of whether rate matching of the data channel for each rate matching resource group is performed using a DCI using a bitmap method. can instruct For example, when four rate matching resources, RMR#1, RMR#2, RMR#3, and RMR#4 are set, the base station sets RMG#1 = {RMR#1, RMR#2}, RMG# as a rate matching group 2 = {RMR#3, RMR#4} can be set, and using 2 bits in the DCI field, rate matching in RMG#1 and RMG#2 can be indicated to the terminal using a bitmap. For example, "1" may be indicated when rate matching is to be performed, and "0" may be indicated when rate matching is not to be performed.

In 5G, granularity of "RB symbol level" and "RE level" is supported as a method of configuring the above-described rate matching resources in the UE. More specifically, the following setting method may be followed.

RB symbol level

The terminal may receive up to four RateMatchPatterns set for each bandwidth part by higher layer signaling, and one RateMatchPattern may include the following contents.

- As a reserved resource in the bandwidth part, a resource in which time and frequency resource regions of the corresponding reserved resource are set in a combination of an RB level bitmap and a symbol level bitmap on the frequency axis may be included. The reserve resource may span one or two slots. A time domain pattern (periodicityAndPattern) in which time and frequency domains composed of each RB level and symbol level bitmap pair are repeated may be additionally set.

- Time and frequency domain resource areas set as control resource sets within the bandwidth part and resource areas corresponding to time domain patterns set as search space settings in which the corresponding resource areas are repeated may be included.

RE level

The terminal may receive the following contents through higher layer signaling.

- LTE CRS (Cell-specific Reference Signal or Common Reference Signal) configuration information (lte-CRS-ToMatchAround) for the RE corresponding to the pattern, the number of LTE CRS ports (nrofCRS-Ports) and LTE-CRS-vshift(s) values (v-shift), LTE carrier center subcarrier location information (carrierFreqDL) from the reference frequency point (eg, reference point A), LTE carrier bandwidth size (carrierBandwidthDL) information, MBSFN (Multicast-broadcast single -frequency network) and the like corresponding to subframe configuration information (mbsfn-SubframeConfigList). The terminal may determine the position of the CRS in the NR slot corresponding to the LTE subframe based on the above information.

- It may include configuration information about a resource set corresponding to one or a plurality of ZP (Zero Power) CSI-RS in the bandwidth part.

[Related to LTE CRS rate match]

Next, the rate match process for the above-described LTE CRS will be described in detail. For the coexistence of Long Term Evolution (LTE) and New RAT (NR) (LTE-NR Coexistence), NR provides a function for setting a cell specific reference signal (CRS) pattern of LTE to the NR terminal. More specifically, the CRS pattern may be provided by RRC signaling including at least one parameter in a ServingCellConfig Information Element (IE) or a ServingCellConfigCommon IE. Examples of the parameters may include lte-CRS-ToMatchAround, lte-CRS-PatternList1-r16, lte-CRS-PatternList2-r16, crs-RateMatch-PerCORESETPoolIndex-r16, and the like.

The Rel-15 NR provides a function of setting one CRS pattern per serving cell through the lte-CRS-ToMatchAround parameter. In Rel-16 NR, the above function has been extended to enable setting of a plurality of CRS patterns per serving cell. More specifically, one CRS pattern can be set per one LTE carrier in a Single-transmission and reception point (TRP) setting terminal, and two CRS patterns per one LTE carrier in a Multi-TRP setting terminal could be set. For example, up to three CRS patterns per serving cell can be set in a single-TRP configuration terminal through the lte-CRS-PatternList1-r16 parameter. For another example, a CRS may be configured for each TRP in a multi-TRP configuration terminal. That is, the CRS pattern for TRP1 may be set through the lte-CRS-PatternList1-r16 parameter, and the CRS pattern for TRP2 may be set through the lte-CRS-PatternList2-r16 parameter. On the other hand, when two TRPs are set as above, crs-RateMatch-PerCORESETPoolIndex determines whether both the CRS patterns of TRP1 and TRP2 are applied to a specific PDSCH (Physical Downlink Shared Channel) or whether only the CRS pattern for one TRP is applied. It is determined through the -r16 parameter. If the crs-RateMatch-PerCORESETPoolIndex-r16 parameter is set to enabled, only the CRS pattern of one TRP is applied, and in other cases, both CRS patterns of the two TRPs are applied.

Table 26 shows the ServingCellConfig IE including the CRS pattern, and Table 27 shows the RateMatchPatternLTE-CRS IE including at least one parameter for the CRS pattern.

[PDSCH: related to frequency resource allocation]

13 is a diagram illustrating an example of frequency axis resource allocation of a physical downlink shared channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure.

13 shows three frequency axis resource allocation methods of type 0 (13-00), type 1 (13-05), and dynamic switch (13-10) that can be set through upper layers in an NR wireless communication system. It is a drawing showing them.

Referring to FIG. 13, if a UE is configured to use only resource type 0 through higher layer signaling (13-00), some downlink control information (DCI) for allocating a PDSCH to the UE is NRBG number Contains a bitmap made up of bits. Conditions for this will be described later. At this time, NRBG means the number of RBGs (resource block groups) determined as shown in [Table 28] according to the BWP size allocated by the BWP indicator and the upper layer parameter rbg-Size. Data is transmitted to the RBG indicated by 1.

개의 비트들로 구성되는 주파수 축 자원 할당 정보를 포함한다. 이를 위한 조건은 차후 다시 설명된다. 기지국은 이를 통하여 starting VRB(13-20)와 이로부터 연속적으로 할당되는 주파수 축 자원의 길이(13-25)를 설정할 수 있다.If the terminal is configured to use only resource type 1 through higher layer signaling (13-05), some DCIs allocating the PDSCH to the terminal

and frequency axis resource allocation information consisting of N bits. Conditions for this will be described later. Through this, the base station can set the starting VRB (13-20) and the length (13-25) of frequency axis resources continuously allocated therefrom.

If the UE is configured to use both resource type 0 and resource type 1 through higher layer signaling (13-10), some DCIs allocated to the PDSCH to the UE are payloads for configuring resource type 0 (13-15) and frequency axis resource allocation information consisting of bits of a larger value (13-35) among payloads (13-20, 13-25) for setting resource type 1. Conditions for this will be described later. At this time, one bit may be added to the first part (MSB) of the frequency axis resource allocation information in the DCI, and if the corresponding bit has a value of '0', it is indicated that resource type 0 is used, and if the value is '1', resource It may be indicated that type 1 is used.

[PDSCH/PUSCH: related to time resource allocation]

Hereinafter, a time domain resource allocation method for a data channel in a next-generation mobile communication system (5G or NR system) will be described.

The base station provides a table for time domain resource allocation information for a downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH) to the terminal, and higher layer signaling (eg, For example, RRC signaling). For PDSCH, a table consisting of maxNrofDL-Allocations = 16 entries can be set, and for PUSCH, a table consisting of maxNrofUL-Allocations = 16 entries can be set. In one embodiment, the time domain resource allocation information includes the PDCCH-to-PDSCH slot timing (corresponding to a time interval in units of slots between a time when a PDCCH is received and a time when a PDSCH scheduled by the received PDCCH is transmitted, denoted as K0). ), PDCCH-to-PUSCH slot timing (corresponding to the time interval in units of slots between the time when the PDCCH is received and the time when the PUSCH scheduled by the received PDCCH is transmitted, denoted as K2), the PDSCH or PUSCH within the slot Information about the position and length of the scheduled start symbol, mapping type of PDSCH or PUSCH, etc. may be included. For example, information such as [Table 29] or [Table 30] below may be transmitted from the base station to the terminal.

The base station may notify the terminal of one of the above-described table entries for time domain resource allocation information through L1 signaling (eg, DCI) (eg, to be indicated by the 'time domain resource allocation' field in DCI). can). The terminal may obtain time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

14 is a diagram illustrating an example of time axis resource allocation of a PDSCH in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 14, a base station sets subcarrier spacing (SCS) ( μ _PDSCH , μ _PDCCH ) of a data channel and a control channel configured using an upper layer, and scheduling offsets (scheduling The time axis position of the PDSCH resource may be indicated according to the offset) (K0) value and the OFDM symbol start position (14-00) and length (14-05) within one slot dynamically indicated through DCI.

15 is a diagram illustrating an example of time domain resource allocation according to subcarrier intervals of a data channel and a control channel in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 15, when the subcarrier intervals of the data channel and the control channel are the same (15-00, μ _PDSCH = μ _PDCCH ), since the slot numbers for data and control are the same, the base station and the terminal A scheduling offset may be generated according to a predetermined slot offset K0. On the other hand, when the subcarrier intervals of the data channel and the control channel are different (15-05, μ _PDSCH ≠ μ _PDCCH ), since the slot numbers for data and control are different, the base station and the terminal have PDCCH subcarrier intervals. Based on , a scheduling offset may be generated according to a predetermined slot offset K0.

[PDSCH: Processing Time]

Next, PDSCH processing procedure time will be described. When the base station schedules the terminal to transmit the PDSCH using DCI format 1_0, 1_1, or 1_2, the terminal uses the DCI-instructed transmission method (modulation and coding instruction index (MCS), demodulation reference signal related information, time and PDSCH processing time for receiving PDSCH by applying frequency resource allocation information, etc.) may be required. In NR, the PDSCH processing time was defined in consideration of this. The PDSCH processing time of the UE may follow [Equation 3] below.

[Equation 3]

T _proc,1 = (N _One + d _1,1 + d ₂ )( 2048 + 144 ) K2 ^-μ T _c +T _ext

In T _proc,1 described above with Equation 3, each variable may have the following meaning.

- N ₁ : The number of symbols determined according to UE processing capability 1 or 2 and numerology μ according to the capabilities of the UE. If it is reported as UE processing capability 1 according to the UE's capability report, it has the value of [Table 31], and it is reported as UE processing capability 2, and it is set through higher layer signaling that UE processing capability 2 can be used [Table 32] can have a value of The numerology μ may correspond to the minimum value among μ _PDCCH , μ _{PDSCH , and} μ _UL so as to maximize the T _{proc,1 ,} and μ _PDCCH , μ _{PDSCH , and} μ _UL are the numerology and schedule of the PDCCH for which the PDSCH is scheduled, respectively. It may mean the numerology of the received PDSCH and the numerology of the uplink channel through which the HARQ-ACK will be transmitted.

μ PDSCH decoding time N ₁ [symbols] When dmrs-AdditionalPosition = pos0 in DMRS-DownlinkConfig, which is upper layer signaling for both PDSCH mapping type A and B In case that dmrs-AdditionalPosition = pos0 in DMRS-DownlinkConfig, which is higher layer signaling for both PDSCH mapping types A and B, or if higher layer parameters are not set 0 8 N _1,0 One 10 13 2 17 20 3 20 24

μ PDSCH decoding time N ₁ [symbols] When dmrs-AdditionalPosition = pos0 in DMRS-DownlinkConfig, which is upper layer signaling for both PDSCH mapping type A and B 0 3 One 4.5 2 9 for frequency range 1

- K: 64

- T _ext : When the UE uses the shared spectrum channel access method, the UE may calculate T _ext and apply it to the PDSCH processing time. Otherwise, T _ext is assumed to be zero.

- If l ₁ representing the PDSCH DMRS position value is 12, N1,0 in [Table 31] has a value of 14, otherwise it has a value of 13.

- For PDSCH mapping type A, the last symbol of the PDSCH is the ith symbol in the slot in which the PDSCH is transmitted, and if i < 7, d _1,1 is 7-i, otherwise d _1,1 is 0.

-d ₂ : When a PUCCH with a high priority index and a PUCCH or PUSCH with a low priority index overlap in time, d ₂ of the PUCCH with a high priority index may be set to a value reported from the UE. Otherwise, d ₂ is 0.

- When PDSCH mapping type B is used for UE processing capability 1, the value of d _1,1 is the number of symbols L, which is the number of symbols of the scheduled PDSCH, and the PDCCH scheduling the PDSCH and the scheduled PDSCH. Depending on d, the number of overlapping symbols can be determined

- If L ≥ 7, then d _1,1 = 0.

- if L ≥ 4 and L ≤ 6, then d _1,1 = 7 - L.

- if L = 3, then d _1,1 = min (d, 1).

- If L = 2, then d _1,1 = 3 + d.

- When PDSCH mapping type B is used for UE processing capability 2, the value of d _1,1 is the number of symbols L of the scheduled PDSCH and the number of overlapping symbols between the PDCCH scheduling the PDSCH and the scheduled PDSCH as follows. Depending on d can be determined

- If L ≥ 7, then d _1,1 = 0.

- if L ≥ 4 and L ≤ 6, then d _1,1 = 7 - L.

- if L = 2,

- If the scheduling PDCCH exists in a CORESET consisting of 3 symbols, and the CORESET and the scheduled PDSCH have the same start symbol, d _1,1 = 3.

- otherwise, d _1,1 = d.

- In the case of a UE supporting capability 2 within a given serving cell, PDSCH processing time according to UE processing capability 2 can be applied when the UE sets processingType2Enabled, which is higher layer signaling, to enable for the corresponding cell.

If the position of the first uplink transmission symbol of the PUCCH including the HARQ-ACK information ( K ₁ defined as the transmission time of the HARQ-ACK, the PUCCH resource used for HARQ-ACK transmission, and the timing advance effect may be considered) If it does not start earlier than the first uplink transmission symbol that appears after a time of T _proc,1 from the last symbol of the PDSCH, the UE must transmit a valid HARQ-ACK message. That is, the UE must transmit the PUCCH including the HARQ-ACK only when the PDSCH processing time is sufficient. Otherwise, the terminal cannot provide valid HARQ-ACK information corresponding to the scheduled PDSCH to the base station. The above T _proc,1 can be used for both general and extended CP cases. In the case of a PDSCH composed of two PDSCH transmission positions within one slot, d _1,1 is calculated based on the first PDSCH transmission position within the corresponding slot.

[PDSCH: Receive preparation time for cross-carrier scheduling]

In the case of cross-carrier scheduling in which μ _PDCCH , which is the numerology through which PDCCH to be scheduled next is transmitted, and μ _PDSCH , which is the numerology through which PDSCH scheduled through the corresponding PDCCH is transmitted, are different from each other, the UE defined for the time interval between the PDCCH and the PDSCH The PDSCH reception preparation time of N _pdsch will be described.

If μ _PDCCH < μ _PDSCH , the scheduled PDSCH cannot be transmitted earlier than the first symbol of the slot following N _pdsch symbols from the last symbol of the PDCCH that scheduled the corresponding PDSCH. A transmission symbol of the corresponding PDSCH may include a DM-RS.

If μ _PDCCH > μ _PDSCH , the scheduled PDSCH may be transmitted from N _pdsch symbols after the last symbol of the PDCCH that scheduled the corresponding PDSCH. A transmission symbol of the corresponding PDSCH may include a DM-RS.

Table 33 shows an example of N _pdsch according to the scheduled PDCCH subcarrier interval.

μ _PDCCH N _pdsch [symbols] 0 4 One 5 2 10 3 14

[PDSCH: TCI state activation MAC-CE]

Next, a beam configuration method for the PDSCH will be described. 16 illustrates a process for configuring and activating a PDSCH beam. The list of TCI states for the PDSCH may be indicated through an upper layer list such as RRC (16-00). The list of the TCI states may be indicated, for example, by tci-StatesToAddModList and/or tci-StatesToReleaseList in the PDSCH-Config IE for each BWP. Next, some of the list of TCI states can be activated through MAC-CE (16-20). The maximum number of activated TCI states may be determined according to capabilities reported by the UE. (16-50) shows an example of a MAC-CE structure for PDSCH TCI state activation/deactivation.

Table 34 shows the meaning of each field in the MAC CE and values that can be set for each field.

- Serving Cell ID (Serving Cell Identifier): This field indicates the identity of the Serving Cell for which the MAC CE applies. The length of the field is 5 bits. If the indicated Serving Cell is configured as part of a simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 as specified in TS 38.331 [5], this MAC CE applies to all the Serving Cells configured in the set simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2, respectively;
- BWP ID (Bandwidth Part Identifier): This field indicates a DL BWP for which the MAC CE applies as the codepoint of the DCI bandwidth part indicator field as specified in TS 38.212 [9]. The length of the BWP ID field is 2 bits. This field is ignored if this MAC CE applies to a set of Serving Cells;
-T _i (TCI state identifier): If there is a TCI state with TCI-StateId i as specified in TS 38.331 [5], this field indicates the activation/deactivation status of the TCI state with TCI-StateId i, otherwise MAC entity shall ignore the Ti field. The Ti field is set to 1 to indicate that the TCI state with TCI-StateId i shall be activated and mapped to the codepoint of the DCI Transmission Configuration Indication field, as specified in TS 38.214 [7]. The Ti field is set to 0 to indicate that the TCI state with TCI-StateId i shall be deactivated and is not mapped to the codepoint of the DCI Transmission Configuration Indication field. The codepoint to which the TCI State is mapped is determined by its ordinal position among all the TCI States with Ti field set to 1, ie the first TCI State with T _i field set to 1 shall be mapped to the codepoint value 0, second TCI State with Ti field set to 1 shall be mapped to the codepoint value 1 and so on. The maximum number of activated TCI states is 8;
- CORESET Pool ID (CORESET Pool ID identifier): This field indicates that mapping between the activated TCI states and the codepoint of the DCI Transmission Configuration Indication set by field Ti is specific to the ControlResourceSetId configured with CORESET Pool ID as specified in TS 38.331 [ 5]. This field set to 1 indicates that this MAC CE shall be applied for the DL transmission scheduled by CORESET with the CORESET pool ID equal to 1, otherwise, this MAC CE shall be applied for the DL transmission scheduled by CORESET pool ID equal to 0. If the coresetPoolIndex is not configured for any CORESET, MAC entity shall ignore the CORESET Pool ID field in this MAC CE when receiving the MAC CE. If the Serving Cell in the MAC CE is configured in a cell list that contains more than one Serving Cell, the CORESET Pool ID field shall be ignored when receiving the MAC CE.

[SRS related]

Next, a method for estimating an uplink channel using Sounding Reference Signal (SRS) transmission of a terminal will be described. The base station may set at least one SRS configuration for each uplink BWP to deliver configuration information for SRS transmission to the terminal, and may also set at least one SRS resource set for each SRS configuration. As an example, the base station and the terminal may send and receive higher signaling information as follows to deliver information about the SRS resource set.

- srs-ResourceSetId: SRS resource set index

- srs-ResourceIdList: A set of SRS resource indexes referenced by the SRS resource set

- resourceType: Time axis transmission setting of the SRS resource referenced by the SRS resource set, which can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. If set to 'periodic' or 'semi-persistent', associated CSI-RS information may be provided according to the usage of the SRS resource set. If set to 'aperiodic', an aperiodic SRS resource trigger list and slot offset information may be provided, and associated CSI-RS information may be provided according to the usage of the SRS resource set.

- usage: This is a setting for the usage of the SRS resource referenced by the SRS resource set, and can be set to one of 'beamManagement', 'codebook', 'nonCodebook', and 'antennaSwitching'.

- alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter settings for adjusting the transmission power of the SRS resource referenced by the SRS resource set.

The UE can understand that the SRS resource included in the set of SRS resource indexes referenced by the SRS resource set follows the information set in the SRS resource set.

In addition, the base station and the terminal may transmit and receive higher layer signaling information to deliver individual configuration information for the SRS resource. As an example, the individual configuration information for the SRS resource may include time-frequency axis mapping information within a slot of the SRS resource, which may include information on frequency hopping within a slot or between slots of the SRS resource. . In addition, the individual configuration information for the SRS resource may include time axis transmission configuration of the SRS resource, and may be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. This may be limited to having a time axis transmission setting such as an SRS resource set including an SRS resource. If the time axis transmission setting of the SRS resource is set to 'periodic' or 'semi-persistent', an additional SRS resource transmission period and slot offset (eg, periodicityAndOffset) may be included in the time axis transmission setting.

The base station may activate, deactivate, or trigger SRS transmission to the terminal through higher layer signaling including RRC signaling or MAC CE signaling, or L1 signaling (eg, DCI). For example, the base station may activate or deactivate periodic SRS transmission through higher layer signaling to the terminal. The base station may instruct to activate an SRS resource set in which resourceType is set to periodic through higher layer signaling, and the terminal may transmit an SRS resource referred to in the activated SRS resource set. Time-frequency axis resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and slot mapping including transmission period and slot offset follows periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource may refer to spatial relation info set in the SRS resource or associated CSI-RS information set in the SRS resource set including the SRS resource. The UE may transmit the SRS resource within the uplink BWP activated for the periodic SRS resource activated through higher layer signaling.

For example, the base station may activate or deactivate semi-persistent SRS transmission through higher layer signaling to the terminal. The base station may instruct to activate the SRS resource set through MAC CE signaling, and the terminal may transmit the SRS resource referred to in the activated SRS resource set. An SRS resource set activated through MAC CE signaling may be limited to an SRS resource set whose resourceType is set to semi-persistent. Time-frequency axis resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and slot mapping including transmission period and slot offset follows periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource may refer to spatial relation info set in the SRS resource or associated CSI-RS information set in the SRS resource set including the SRS resource. If spatial relation info is set in the SRS resource, instead of following it, a spatial domain transmission filter may be determined by referring to configuration information on spatial relation info transmitted through MAC CE signaling for activating semi-persistent SRS transmission. The UE may transmit the SRS resource within the uplink BWP activated for the semi-persistent SRS resource activated through higher layer signaling.

For example, the base station may trigger aperiodic SRS transmission to the terminal through DCI. The base station may indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) through the SRS request field of the DCI. The UE can understand that the SRS resource set including the aperiodic SRS resource trigger indicated through the DCI in the aperiodic SRS resource trigger list among the configuration information of the SRS resource set has been triggered. The UE may transmit the SRS resource referred to in the triggered SRS resource set. Time-frequency axis resource mapping within a slot of a transmitted SRS resource follows resource mapping information set in the SRS resource. In addition, slot mapping of the transmitted SRS resource may be determined through a slot offset between the PDCCH including DCI and the SRS resource, which may refer to value (s) included in a slot offset set set in the SRS resource set. Specifically, the slot offset between the PDCCH including the DCI and the SRS resource may apply a value indicated by the time domain resource assignment field of the DCI among the offset value(s) included in the slot offset set set in the SRS resource set. In addition, the spatial domain transmission filter applied to the transmitted SRS resource may refer to spatial relation info set in the SRS resource or associated CSI-RS information set in the SRS resource set including the SRS resource. The UE may transmit an SRS resource within an activated uplink BWP for an aperiodic SRS resource triggered through DCI.

When the base station triggers aperiodic SRS transmission to the terminal through DCI, in order for the terminal to transmit the SRS by applying the configuration information for the SRS resource, the minimum A time interval of (minimum time interval) may be required. The time interval for SRS transmission of the UE is defined as the number of symbols between the last symbol of the PDCCH including the DCI triggering aperiodic SRS transmission and the first symbol to which the first transmitted SRS resource among transmitted SRS resource(s) is mapped. can The minimum time interval may be determined by referring to the PUSCH preparation procedure time required for the UE to prepare for PUSCH transmission. In addition, the minimum time interval may have a different value depending on where an SRS resource set including a transmitted SRS resource is used. For example, the minimum time interval may be defined as an N2 symbol defined by referring to the PUSCH preparation procedure time of the UE and considering UE processing capability according to the capability of the UE. In addition, considering the usage of the SRS resource set including the transmitted SRS resource, if the usage of the SRS resource set is set to 'codebook' or 'antennaSwitching', the minimum time interval is set as N2 symbol, and the usage of the SRS resource set is 'nonCodebook' Alternatively, when set to 'beamManagement', the minimum time interval can be set to N2+14 symbols. The UE transmits the aperiodic SRS when the time interval for aperiodic SRS transmission is greater than or equal to the minimum time interval, and ignores the DCI triggering the aperiodic SRS when the time interval for aperiodic SRS transmission is less than the minimum time interval. can

SRS-Resource ::= SEQUENCE {
srs-ResourceId SRS-ResourceId,
nrofSRS-Ports ENUMERATED {port1, ports2, ports4},
ptrs-PortIndex ENUMERATED {n0, n1 } OPTIONAL, -- Need R
transmissionComb CHOICE {
n2 SEQUENCE {
combOffset-n2 INTEGER (0..1),
cyclicShift-n2 INTEGER (0..7)
},
n4 SEQUENCE {
combOffset-n4 INTEGER (0..3),
cyclicShift-n4 INTEGER (0..11)
}
},
resourceMapping SEQUENCE {
startPosition INTEGER (0..5),
nrofSymbols ENUMERATED {n1, n2, n4},
repetitionFactor ENUMERATED {n1, n2, n4}
},
freqDomainPosition INTEGER (0..67),
freqDomainShift INTEGER (0..268),
freqHopping SEQUENCE {
c-SRS INTEGER (0..63),
b-SRS INTEGER (0..3),
b-hop INTEGER (0..3)
},
groupOrSequenceHopping ENUMERATED { neither, groupHopping, sequenceHopping },
resourceType CHOICE {
aperiodic SEQUENCE {
...
},
semi-persistent SEQUENCE {
periodicityAndOffset-sp SRS-PeriodicityAndOffset,
...
},
periodic SEQUENCE {
periodicityAndOffset-p SRS-PeriodicityAndOffset,
...
}
},
sequenceId INTEGER (0..1023),
spatialRelationInfo SRS-SpatialRelationInfo OPTIONAL, -- Need R
...
}

The spatialRelationInfo setting information in [Table 35] refers to one reference signal and applies the beam information of the reference signal to the beam used for the corresponding SRS transmission. For example, the setting of spatialRelationInfo may include information such as the following [Table 36].

SRS-SpatialRelationInfo ::= SEQUENCE {
servingCellId ServCellIndex OPTIONAL, -- Need S
referenceSignal CHOICE {
ssb-Index SSB-Index,
csi-RS-Index NZP-CSI-RS-ResourceId,
srs SEQUENCE {
resourceId SRS-ResourceId,
uplinkBWP BWP-Id
}
}
}

Referring to the spatialRelationInfo setting, an SS/PBCH block index, CSI-RS index, or SRS index may be set as an index of a reference signal to be referred to in order to use beam information of a specific reference signal. Higher signaling referenceSignal is setting information indicating which beam information of a reference signal is referred to for transmission of the corresponding SRS, ssb-Index is the index of the SS/PBCH block, csi-RS-Index is the index of the CSI-RS, and srs is the index of the SRS. each index. If the value of higher signaling referenceSignal is set to 'ssb-Index', the terminal can apply the RX beam used when receiving the SS/PBCH block corresponding to the ssb-Index as the transmit beam of the corresponding SRS transmission. If the value of higher signaling referenceSignal is set to 'csi-RS-Index', the UE can apply the Rx beam used when receiving the CSI-RS corresponding to the csi-RS-Index as the Tx beam of the corresponding SRS transmission. . If the value of higher signaling referenceSignal is set to 'srs', the terminal can apply the transmission beam used when transmitting the SRS corresponding to srs as the transmission beam of the corresponding SRS transmission.

[PUSCH: related to transmission method]

Next, a scheduling method for PUSCH transmission will be described. PUSCH transmission can be dynamically scheduled by a UL grant in DCI or operated by configured grant Type 1 or Type 2. Dynamic scheduling indication for PUSCH transmission is available in DCI format 0_0 or 0_1.

Configured grant Type 1 PUSCH transmission can be semi-statically set through reception of configuredGrantConfig including rrc-ConfiguredUplinkGrant of [Table 37] through higher signaling without reception of UL grant in DCI. Configured grant Type 2 PUSCH transmission can be scheduled semi-persistently by UL grant in DCI after receiving configuredGrantConfig not including rrc-ConfiguredUplinkGrant in [Table 37] through higher signaling. When PUSCH transmission operates by configured grant, parameters applied to PUSCH transmission are [Except for dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, scaling of UCI-OnPUSCH provided by push-Config of [Table 38], which is an upper signaling. It is applied through configuredGrantConfig, which is the upper signaling of Table 37]. If the terminal is provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 37], the terminal applies tp-pi2BPSK in push-Config of [Table 38] to PUSCH transmission operated by the configured grant.

ConfiguredGrantConfig ::= SEQUENCE {
frequencyHopping ENUMERATED {intraSlot, interSlot} OPTIONAL, -- Need S,
cg-DMRS-Configuration DMRS-UplinkConfig,
mcs-Table ENUMERATED {qam256, qam64LowSE} OPTIONAL, -- Need S
mcs-TableTransformPrecoder ENUMERATED {qam256, qam64LowSE} OPTIONAL, -- Need S
uci-OnPUSCH SetupRelease { CG-UCI-OnPUSCH } OPTIONAL, -- Need M
resourceAllocation ENUMERATED { resourceAllocationType0, resourceAllocationType1, dynamicSwitch },
rbg-Size ENUMERATED {config2} OPTIONAL, -- Need S
powerControlLoopToUse ENUMERATED {n0, n1},
p0-PUSCH-Alpha P0-PUSCH-AlphaSetId;
transformPrecoder ENUMERATED {enabled, disabled} OPTIONAL, -- Need S
nrofHARQ-Processes INTEGER(1..16),
repK ENUMERATED {n1, n2, n4, n8},
repK-RV ENUMERATED {s1-0231, s2-0303, s3-0000} OPTIONAL, -- Need R
periodicity ENUMERATED {
sym2, sym7, sym1x14, sym2x14, sym4x14, sym5x14, sym8x14, sym10x14, sym16x14, sym20x14,
sym32x14, sym40x14, sym64x14, sym80x14, sym128x14, sym160x14, sym256x14, sym320x14, sym512x14,
sym640x14, sym1024x14, sym1280x14, sym2560x14, sym5120x14,
sym6, sym1x12, sym2x12, sym4x12, sym5x12, sym8x12, sym10x12, sym16x12, sym20x12, sym32x12,
sym40x12, sym64x12, sym80x12, sym128x12, sym160x12, sym256x12, sym320x12, sym512x12, sym640x12,
sym1280x12, sym2560x12
},
configuredGrantTimer INTEGER (1..64) OPTIONAL, -- Need R
rrc-ConfiguredUplinkGrant SEQUENCE {
timeDomainOffset INTEGER (0..5119),
timeDomainAllocation INTEGER (0..15),
frequencyDomainAllocation BIT STRING (SIZE(18)),
antennaPort INTEGER (0..31),
dmrs-SeqInitialization INTEGER (0..1) OPTIONAL, -- Need R
precodingAndNumberOfLayers INTEGER (0..63),
srs-ResourceIndicator INTEGER (0..15) OPTIONAL, -- Need R
mcsAndTBS INTEGER (0..31),
frequencyHoppingOffset INTEGER (1.. maxNrofPhysicalResourceBlocks-1) OPTIONAL, -- Need R
pathlossReferenceIndex INTEGER(0..maxNrofPUSCH-PathlossReferenceRSs-1),
...
} OPTIONAL, -- Need R
...
}

Next, a PUSCH transmission method will be described. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission can follow a codebook-based transmission method and a non-codebook-based transmission method, respectively, depending on whether the value of txConfig in push-Config of [Table 38], which is an upper signaling, is 'codebook' or 'nonCodebook'.

As described above, PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can be semi-statically set by configured grant. If the UE is instructed to schedule PUSCH transmission through DCI format 0_0, the UE performs PUSCH transmission using the pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the uplink BWP activated in the serving cell. Beam configuration for transmission is performed, and at this time, PUSCH transmission is based on a single antenna port. The UE does not expect scheduling for PUSCH transmission through DCI format 0_0 in a BWP in which PUCCH resource including pucch-spatialRelationInfo is not configured. If the UE is not configured with txConfig in push-Config of [Table 38], the UE does not expect to be scheduled in DCI format 0_1.

PUSCH-Config ::= SEQUENCE {
dataScramblingIdentityPUSCH INTEGER (0..1023) OPTIONAL, -- Need S
txConfig ENUMERATED {codebook, nonCodebook} OPTIONAL, -- Need S
dmrs-UplinkForPUSCH-MappingTypeA SetupRelease { DMRS-UplinkConfig } OPTIONAL, -- Need M
dmrs-UplinkForPUSCH-MappingTypeB SetupRelease { DMRS-UplinkConfig } OPTIONAL, -- Need M

pushch-PowerControl PUSCH-PowerControl OPTIONAL, -- Need M
frequencyHopping ENUMERATED {intraSlot, interSlot} OPTIONAL, -- Need S
frequencyHoppingOffsetLists SEQUENCE (SIZE (1..4)) OF INTEGER (1.. maxNrofPhysicalResourceBlocks-1)
OPTIONAL, -- Need M
resourceAllocation ENUMERATED { resourceAllocationType0, resourceAllocationType1, dynamicSwitch},
pusch-TimeDomainAllocationList SetupRelease { PUSCH-TimeDomainResourceAllocationList } OPTIONAL, -- Need M
pusch-AggregationFactor ENUMERATED { n2, n4, n8 } OPTIONAL, -- Need S
mcs-Table ENUMERATED {qam256, qam64LowSE} OPTIONAL, -- Need S
mcs-TableTransformPrecoder ENUMERATED {qam256, qam64LowSE} OPTIONAL, -- Need S
transformPrecoder ENUMERATED {enabled, disabled} OPTIONAL, -- Need S
codebookSubset ENUMERATED {fullyAndPartialAndNonCoherent, partialAndNonCoherent,nonCoherent}
OPTIONAL, -- Cond codebookBased
maxRank INTEGER (1..4) OPTIONAL, -- Cond codebookBased
rbg-Size ENUMERATED { config2} OPTIONAL, -- Need S
uci-OnPUSCH SetupRelease { UCI-OnPUSCH} OPTIONAL, -- Need M
tp-pi2BPSK ENUMERATED {enabled} OPTIONAL, -- Need S
...
}

Next, codebook-based PUSCH transmission will be described. Codebook-based PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can operate quasi-statically by configured grant. If the codebook-based PUSCH is dynamically scheduled by DCI format 0_1 or quasi-statically configured by configured grant, the UE uses the SRS Resource Indicator (SRI), Transmission Precoding Matrix Indicator (TPMI), and transmission rank (PUSCH transmission layer number), a precoder for PUSCH transmission is determined.

At this time, SRI may be given through a field SRS resource indicator in DCI or set through higher signaling, srs-ResourceIndicator. When transmitting codebook-based PUSCH, the terminal receives at least one SRS resource, and can receive up to two SRS resources. When a UE receives SRI through DCI, the SRS resource indicated by the corresponding SRI means an SRS resource corresponding to the SRI among SRS resources transmitted prior to the PDCCH including the corresponding SRI. In addition, TPMI and transmission rank may be given through a field precoding information and number of layers in DCI or set through precodingAndNumberOfLayers, which is a higher level signaling. TPMI is used to indicate a precoder applied to PUSCH transmission. If the UE is configured with one SRS resource, TPMI is used to indicate a precoder to be applied in the configured one SRS resource. If the UE is configured with a plurality of SRS resources, TPMI is used to indicate a precoder to be applied in the SRS resource indicated through the SRI.

A precoder to be used for PUSCH transmission is selected from an uplink codebook having the same number of antenna ports as the value of nrofSRS-Ports in SRS-Config, which is higher signaling. In codebook-based PUSCH transmission, the UE determines a codebook subset based on TPMI and codebookSubset in push-Config, which is higher signaling. CodebookSubset in push-Config, which is higher signaling, may be set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability reported by the terminal to the base station. If the terminal reports 'partialAndNonCoherent' as the UE capability, the terminal does not expect the value of codebookSubset, which is higher signaling, to be set to 'fullyAndPartialAndNonCoherent'. In addition, if the terminal reports 'nonCoherent' as the UE capability, the terminal does not expect the value of codebookSubset, which is higher signaling, to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. When nrofSRS-Ports in SRS-ResourceSet, which is higher signaling, indicates two SRS antenna ports, the UE does not expect the value of codebookSubset, which is higher signaling, to be set to 'partialAndNonCoherent'.

The terminal can receive one SRS resource set in which the value of usage in the SRS-ResourceSet, which is higher signaling, is set to 'codebook', and one SRS resource in the corresponding SRS resource set can be indicated through SRI. If several SRS resources are set in an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', the UE sets the same value for all SRS resources in the nrofSRS-Ports value in the upper signaling SRS-Resource. expect this to be set.

The terminal transmits one or more SRS resources included in the SRS resource set in which the value of usage is set to 'codebook' to the base station according to higher signaling, and the base station selects one of the SRS resources transmitted by the terminal to correspond to the SRS Instructs the UE to perform PUSCH transmission using the transmission beam information of the resource. At this time, in codebook-based PUSCH transmission, SRI is used as information for selecting an index of one SRS resource and is included in DCI. Additionally, the base station includes information indicating the TPMI and rank to be used by the terminal for PUSCH transmission in the DCI. The UE performs PUSCH transmission by using the SRS resource indicated by the SRI and applying the rank indicated by the transmission beam of the corresponding SRS resource and the precoder indicated by the TPMI.

Next, non-codebook based PUSCH transmission will be described. Non-codebook based PUSCH transmission can be dynamically scheduled through DCI format 0_0 or 0_1, and can operate quasi-statically by configured grant. When at least one SRS resource is set in an SRS resource set in which the value of usage in the SRS-ResourceSet, which is higher signaling, is set to 'nonCodebook', the terminal can receive non-codebook based PUSCH transmission scheduling through DCI format 0_1.

For an SRS resource set in which the value of usage in the SRS-ResourceSet, which is higher signaling, is set to 'nonCodebook', the terminal can receive one connected NZP CSI-RS resource (non-zero power CSI-RS). The UE may calculate a precoder for SRS transmission through measurement of NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource associated with the SRS resource set and the first symbol of aperiodic SRS transmission in the UE is less than 42 symbols, the UE updates the information on the precoder for SRS transmission. don't expect to be

When the value of resourceType in SRS-ResourceSet, which is higher signaling, is set to 'aperiodic', the connected NZP CSI-RS is indicated by SRS request, which is a field in DCI format 0_1 or 1_1. At this time, if the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the connected NZP CSI-RS exists when the value of the field SRS request in DCI format 0_1 or 1_1 is not '00' will point to At this time, the corresponding DCI must not indicate cross carrier or cross BWP scheduling. In addition, if the value of the SRS request indicates the existence of the NZP CSI-RS, the corresponding NZP CSI-RS is located in the slot where the PDCCH including the SRS request field is transmitted. At this time, the TCI states set for the scheduled subcarriers are not set to QCL-TypeD.

If a periodic or semi-persistent SRS resource set is configured, the connected NZP CSI-RS may be indicated through associatedCSI-RS in the SRS-ResourceSet, which is higher signaling. For non-codebook based transmission, the UE does not expect spatialRelationInfo, which is higher signaling for SRS resource, and associatedCSI-RS in SRS-ResourceSet, which is higher signaling, to be set together.

When a plurality of SRS resources are configured, the UE may determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. At this time, SRI may be indicated through a field SRS resource indicator in DCI or set through higher signaling, srs-ResourceIndicator. Similar to the above codebook-based PUSCH transmission, when a UE receives SRI through DCI, the SRS resource indicated by the corresponding SRI selects the SRS resource corresponding to the SRI among the SRS resources transmitted prior to the PDCCH including the corresponding SRI. it means. The UE can use one or a plurality of SRS resources for SRS transmission, and the maximum number of SRS resources that can be simultaneously transmitted in the same symbol within one SRS resource set and the maximum number of SRS resources are determined by the UE capability reported by the UE to the base station. It is decided. At this time, SRS resources transmitted simultaneously by the UE occupy the same RB. The UE configures one SRS port for each SRS resource. Only one SRS resource set in which the value of usage in the SRS-ResourceSet, which is an upper signaling, is set to 'nonCodebook' can be set, and up to four SRS resources for non-codebook based PUSCH transmission can be set.

The base station transmits one NZP-CSI-RS associated with the SRS resource set to the terminal, and the terminal transmits one or more SRS resources in the corresponding SRS resource set based on the measurement result when receiving the corresponding NZP-CSI-RS Calculate the precoder to use when transmitting. The terminal applies the calculated precoder when transmitting one or more SRS resources in the SRS resource set with usage set to 'nonCodebook' to the base station, and the base station uses one or more of the one or more SRS resources received. Select SRS resource. At this time, in non-codebook based PUSCH transmission, SRI indicates an index capable of expressing a combination of one or a plurality of SRS resources, and the SRI is included in DCI. At this time, the number of SRS resources indicated by the SRI transmitted by the base station may be the number of transmission layers of the PUSCH, and the UE transmits the PUSCH by applying a precoder applied to transmission of the SRS resource to each layer.

[PUSCH: Preparatory Course Hours]

Next, the PUSCH preparation procedure time will be described. When the base station schedules the UE to transmit the PUSCH using DCI format 0_0, 0_1, or 0_2, the UE uses the DCI-instructed transmission method (transmission precoding method of SRS resource, number of transmission layers, spatial domain transmission filter) A PUSCH preparation process time may be required to transmit the PUSCH by applying . NR defined the PUSCH preparation process time considering this. The PUSCH preparation process time of the UE may follow [Equation 4] below.

[Equation 4]

T _proc,2 = max(( N ₂ + d _2,1 + d ₂ )( 2048 + 144 ) K2 ^-μ T _c + T _ext + T _switch , d _2,2 )

In T _proc,2 described above with Equation 4, each variable may have the following meaning.

-N ₂ : The number of symbols determined according to UE processing capability 1 or 2 and numerology μ according to the capabilities of the UE. When reported as UE processing capability 1 according to the capability report of the UE, with the value of [Table 39], when reported as UE processing capability 2 and capable of using UE processing capability 2 is set through higher layer signaling [Table 40] can have a value of

-d _2,1 : The number of symbols determined as 0 when all resource elements of the first OFDM symbol of PUSCH transmission are set to consist of only DM-RS, and 1 otherwise.

- K: 64

또는

중, T_proc,2이 더 크게 되는 값을 따른다.

은 PUSCH를 스케줄링 하는 DCI가 포함된 PDCCH가 전송되는 하향링크의 뉴머롤로지를 뜻하고,

은 PUSCH가 전송되는 상향링크의 뉴머롤로지를 뜻한다.- μ:

or

Of which, T _proc,2 follows the larger value.

denotes the numerology of the downlink through which the PDCCH including the DCI scheduling the PUSCH is transmitted,

denotes the numerology of the uplink through which the PUSCH is transmitted.

,

,

를 가진다.- T _c :

,

,

have

-d _2,2 : Follows the BWP switching time when the DCI scheduling the PUSCH indicates BWP switching, otherwise has 0.

- d ₂ : When OFDM symbols of a PUCCH, a PUSCH with a high priority index, and a PUCCH with a low priority index overlap in time, the d ₂ value of the PUSCH with a high priority index is used. Otherwise, d ₂ is 0.

- T _ext : If the UE uses the shared spectrum channel access method, the UE can calculate T _ext and apply it to the PUSCH preparation process time. Otherwise, T _ext is assumed to be zero.

- T _switch : When an uplink switching interval is triggered, T _switch is assumed to be the switching interval time. otherwise, it is assumed to be 0.

When the base station and the terminal consider the time axis resource mapping information of the PUSCH scheduled through the DCI and the effect of the uplink-downlink timing advance, from the last symbol of the PDCCH including the DCI scheduled the PUSCH to after T _proc,2 If the first symbol of the PUSCH starts before the first uplink symbol that the CP starts, it is determined that the PUSCH preparation process time is not sufficient. If not, the base station and the terminal determine that the PUSCH preparation process time is sufficient. The UE may transmit the PUSCH only when the PUSCH preparation time is sufficient, and may ignore the DCI for scheduling the PUSCH when the PUSCH preparation time is not sufficient.

[PUSCH: related to repetitive transmission]

Hereinafter, repetitive transmission of an uplink data channel in a 5G system will be described in detail. The 5G system supports two types, PUSCH repeated transmission type A and PUSCH repeated transmission type B, as repeated transmission methods of an uplink data channel. The UE may be configured with either PUSCH repetitive transmission type A or B through higher layer signaling.

PUSCH repetitive transmission type A

- As described above, the symbol length of the uplink data channel and the location of the start symbol are determined by the time domain resource allocation method within one slot, and the base station sets the number of repeated transmissions through higher layer signaling (eg, RRC signaling) or L1 signaling ( For example, the UE may be notified through DCI).

- The terminal may repeatedly transmit an uplink data channel having the same length and start symbol in consecutive slots based on the number of repeated transmissions received from the base station. At this time, when at least one symbol of a slot set by the base station to the terminal as downlink or a symbol of an uplink data channel configured by the terminal is set to downlink, the terminal skips transmission of the uplink data channel, but uplink The number of repeated transmissions of the data channel is counted.

PUSCH repetitive transmission type B

- As described above, the start symbol and length of the uplink data channel are determined by the time domain resource allocation method within one slot, and the base station transmits the number of repetitions numberofrepetitions through upper signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI) may notify the UE.

에 의해 주어지고 그 슬롯에서 시작하는 심볼은

에 의해 주어진다. n번째 nominal repetition이 끝나는 슬롯은

에 의해 주어지고 그 슬롯에서 끝나는 심볼은

- 에 의해 주어진다. 여기서 n=0,..., numberofrepetitions-1 이고 S는 설정 받은 상향링크 데이터 채널의 시작 심볼 L은 설정 받은 상향링크 데이터 채널의 심볼 길이를 나타낸다.

는 PUSCH 전송이 시작하는 슬롯을 나타내고

슬롯당 심볼의 수를 나타낸다.- - The nominal repetition of the uplink data channel is determined as follows based on the start symbol and length of the uplink data channel that is set first. The slot where the nth nominal repetition starts is

The symbol given by and starting in that slot is

given by The slot where the nth nominal repetition ends is

The symbol given by and ending in that slot is

- is given by Here, n = 0, ..., numberofrepetitions-1, S is the start symbol of the configured uplink data channel, L represents the symbol length of the configured uplink data channel.

Represents a slot in which PUSCH transmission starts

Indicates the number of symbols per slot.-

- The UE determines an invalid symbol for PUSCH repetitive transmission type B. A symbol configured for downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated is determined as an invalid symbol for PUSCH repeated transmission type B. Additionally, invalid symbols can be set in higher-level parameters (e.g. InvalidSymbolPattern). A higher layer parameter (e.g. InvalidSymbolPattern) provides a symbol-level bitmap spanning one slot or two slots so that invalid symbols can be set. 1 in the bitmap represents an invalid symbol. Additionally, the period and pattern of the bitmap may be set through a higher layer parameter (for example, periodicityAndPattern). If a higher layer parameter (eg InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter indicates 1, the terminal applies the invalid symbol pattern, and if the parameter indicates 0, the terminal does not apply the invalid symbol pattern. If the upper layer parameter (eg InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter is not set, the terminal applies the invalid symbol pattern.

After the invalid symbol is determined, for each nominal repetition, the terminal may consider symbols other than the invalid symbol as valid symbols. If more than one valid symbol is included in each nominal repetition, the nominal repetition may include one or more actual repetitions. Here, each actual repetition includes a contiguous set of valid symbols that can be used for PUSCH repeated transmission type B in one slot.

17 is a diagram illustrating an example of PUSCH repeated transmission type B in a wireless communication system according to an embodiment of the present disclosure. The terminal may set the start symbol S of the uplink data channel to 0 and the length L of the uplink data channel to 14, and set the number of repeated transmissions to 16. In this case, nominal repetition is indicated in 16 consecutive slots (1701). After that, the terminal may determine a symbol set as a downlink symbol in each nominal repetition 1701 as an invalid symbol. In addition, the terminal determines symbols set to 1 in invalid symbol pattern 1702 as invalid symbols. In each nominal repetition, when valid symbols, not invalid symbols, consist of one or more consecutive symbols in one slot, they are set as actual repetitions and transmitted (1703).

In addition, for repeated PUSCH transmission, NR Release 16 may define the following additional methods for UL grant-based PUSCH transmission and configured grant-based PUSCH transmission across slot boundaries.

-Method 1 (mini-slot level repetition): Through one UL grant, two or more repeated PUSCH transmissions are scheduled within one slot or across the boundary of consecutive slots. Also, for method 1, time domain resource allocation information in DCI indicates resources of the first repeated transmission. In addition, time domain resource information of the remaining repeated transmissions may be determined according to time domain resource information of the first repeated transmission and an uplink or downlink direction determined for each symbol of each slot. Each repeated transmission occupies consecutive symbols.

- Method 2 (multi-segment transmission): Two or more repeated PUSCH transmissions are scheduled in consecutive slots through one UL grant. At this time, one transmission is designated for each slot, and different start points or repetition lengths may be different for each transmission. Also, in method 2, the time domain resource allocation information in the DCI indicates the start point and repetition length of all repeated transmissions. In addition, when repeated transmission is performed within a single slot through method 2, if there are several bundles of consecutive uplink symbols in the corresponding slot, each repeated transmission is performed for each bundle of uplink symbols. If a bundle of consecutive uplink symbols exists uniquely in the corresponding slot, one repetition of PUSCH transmission is performed according to the method of NR Release 15.

- Method 3: Two or more repeated PUSCH transmissions are scheduled in consecutive slots through two or more UL grants. At this time, one transmission is designated for each slot, and the n-th UL grant can be received before the PUSCH transmission scheduled for the n-1-th UL grant ends.

-Method 4: Through one UL grant or one configured grant, one or several PUSCH repeated transmissions within a single slot, or two or more PUSCH repeated transmissions across the boundary of consecutive slots Can be supported. . The number of repetitions indicated by the base station to the terminal is only a nominal value, and the number of repeated PUSCH transmissions actually performed by the terminal may be greater than the nominal number of repetitions. Time domain resource allocation information within the DCI or within the configured grant means the resource of the first repeated transmission indicated by the base station. Time domain resource information of the remaining repeated transmissions may be determined by referring to resource information of at least the first repeated transmission and uplink or downlink directions of symbols. If the time domain resource information of repeated transmission indicated by the base station spans a slot boundary or includes an uplink/downlink switching point, the repeated transmission may be divided into a plurality of repeated transmissions. In this case, one repetitive transmission may be included for each uplink period in one slot.

[PUSCH: frequency hopping process]

In the following, frequency hopping of an uplink data channel (Physical Uplink Shared Channel, PUSCH) in a 5G system will be described in detail.

In 5G, as a frequency hopping method of an uplink data channel, two methods are supported for each PUSCH repeated transmission type. First, PUSCH repetition transmission type A supports intra-slot frequency hopping and inter-slot frequency hopping, and PUSCH repetition transmission type B supports inter-repetition frequency hopping and inter-slot frequency hopping.

The intra-slot frequency hopping method supported by PUSCH repetitive transmission type A is a method in which a terminal changes and transmits allocated resources in a frequency domain by a set frequency offset in two hops within one slot. In intra-slot frequency hopping, the starting RB of each hop can be expressed through Equation 5.

[Equation 5]

는 UL BWP안에서 시작 RB를 나타내고 주파수 자원 할당 방법으로부터 계산된다.

은 상위 계층 파라미터를 통해 두개의 홉 사이에 주파수 오프셋을 나타난다. 첫번째 홉의 심볼 수는

로 나타낼 수 있고, 두번째 홉의 심볼 수는

으로 나타낼 수 있다.

은 한 슬롯 내에서의 PUSCH 전송의 길이로, OFDM 심볼 수로 나타난다.In Equation 5, i = 0 and i = 1 represent the first hop and the second hop, respectively,

denotes the starting RB in the UL BWP and is calculated from the frequency resource allocation method.

represents a frequency offset between two hops through an upper layer parameter. The number of symbols in the first hop is

, and the number of symbols in the second hop is

can be expressed as

is the length of PUSCH transmission within one slot and is represented by the number of OFDM symbols.

슬롯 동안 시작 RB는 수학식 6을 통해 나타낼 수 있다.Next, the inter-slot frequency hopping method supported by PUSCH repetitive transmission types A and B is a method in which the UE changes and transmits allocated resources in the frequency domain by a set frequency offset for each slot. In Inter-slot frequency hopping

A starting RB during a slot can be expressed through Equation 6.

[Equation 6]

는 multi-slot PUSCH 전송에서 현재 슬롯 번호,

는 UL BWP안에서 시작 RB를 나타내고 주파수 자원 할당 방법으로부터 계산된다.

은 상위 계층 파라미터를 통해 두개의 홉 사이에 주파수 오프셋을 나타낸다.In Equation 6,

is the current slot number in multi-slot PUSCH transmission,

denotes the starting RB in the UL BWP and is calculated from the frequency resource allocation method.

represents a frequency offset between two hops through a higher layer parameter.

Next, the inter-repetition frequency hopping method supported by PUSCH repeated transmission type B moves and transmits resources allocated in the frequency domain for one or a plurality of actual repetitions within each nominal repetition by a set frequency offset. RB _start (n), which is an index of a start RB in the frequency domain for one or a plurality of actual repetitions within the n-th nominal repetition, may follow Equation 7 below.

[Equation 7]

은 상위 계층 파라미터를 통해 두 개의 홉 사이에 RB 오프셋을 나타낸다.In Equation 7, n is the index of nominal repetition,

represents an RB offset between two hops through a higher layer parameter.

[Regarding device ability reporting]

In LTE and NR, the terminal may perform a procedure for reporting the capability supported by the terminal to the corresponding base station while connected to the serving base station. In the description below, this is referred to as a UE capability report.

The base station may transmit a UE capability inquiry message requesting a capability report to a UE in a connected state. The message may include a UE capability request for each radio access technology (RAT) type of the base station. The request for each RAT type may include supported frequency band combination information. In addition, in the case of the terminal capability inquiry message, UE capabilities for each RAT type may be requested through one RRC message container transmitted by the base station, or the base station sends a terminal capability inquiry message including a terminal capability request for each RAT type. It can be included multiple times and delivered to the terminal. That is, the UE capability query is repeated multiple times within one message, and the UE can configure and report a UE capability information message corresponding to the UE capability information message multiple times. In the next-generation mobile communication system, a UE capability request for MR-DC (Multi-RAT dual connectivity) including NR, LTE, and EN-DC (E-UTRA-NR dual connectivity) can be requested. In addition, although the terminal capability inquiry message is generally initially transmitted after the terminal connects to the base station, the base station may request it under any condition when necessary.

In the above step, the terminal receiving the UE capability report request from the base station configures the terminal capability according to the RAT type and band information requested from the base station. Below is a summary of how the UE configures UE capabilities in the NR system.

One. If the terminal receives a list of LTE and/or NR bands from the base station as a UE capability request, the terminal configures a band combination (BC) for EN-DC and NR stand alone (SA). That is, BC candidate lists for EN-DC and NR SA are configured based on the bands requested to the base station through FreqBandList. In addition, bands have priorities in the order described in FreqBandList.

2. If the base station requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the terminal completely removes those for NR SA BCs from the configured BC candidate list. This operation may occur only when the LTE base station (eNB) requests the “eutra” capability.

3. Thereafter, the terminal removes fallback BCs from the candidate list of BCs configured in the above step. Here, the fallback BC means a BC that can be obtained by removing a band corresponding to at least one SCell from any BC, and since the BC before removing the band corresponding to at least one SCell can already cover the fallback BC, can be omitted. This step also applies to MR-DC, ie LTE bands as well. The remaining BCs after this step are the final "candidate BC list".

4. The terminal selects BCs to be reported by selecting BCs suitable for the requested RAT type from the final "candidate BC list". In this step, the terminal configures the supportedBandCombinationList in a predetermined order. That is, the terminal configures the BC and UE capabilities to be reported according to the order of the preset rat-Type. (nr -> eutra-nr -> eutra). In addition, featureSetCombination is configured for the configured supportedBandCombinationList, and a list of "candidate feature set combination" is configured in the candidate BC list from which the list for fallback BC (including capabilities of the same or lower level) is removed. The above "candidate feature set combination" includes both feature set combinations for NR and EUTRA-NR BC, and can be obtained from the feature set combination of the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

5. In addition, if the requested rat Type is eutra-nr and has an effect, featureSetCombinations is included in both containers of UE-MRDC-Capabilities and UE-NR-Capabilities. However, the feature set of NR includes only UE-NR-Capabilities.

After the terminal capabilities are configured, the terminal transmits a terminal capability information message including the terminal capabilities to the base station. Based on the terminal capabilities received from the terminal, the base station then performs appropriate scheduling and transmission/reception management for the corresponding terminal.

[CA/DC related]

18 is a diagram illustrating a radio protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation according to an embodiment of the present disclosure.

Referring to FIG. 18, the wireless protocols of the next-generation mobile communication system are NR SDAP (Service Data Adaptation Protocol S25, S70), NR PDCP (Packet Data Convergence Protocol S30, S65), NR RLC (Radio Link Control) in the terminal and NR base station, respectively. S35, S60) and NR MAC (Medium Access Control S40, S55).

The main functions of the NR SDAP (S25, S70) may include some of the following functions.

- Transfer of user plane data

- A mapping function between a QoS flow and a data bearer for uplink and downlink (mapping between a QoS flow and a DRB for both DL and UL)

- Marking function of QoS flow ID for uplink and downlink (marking QoS flow ID in both DL and UL packets)

- Function to map reflective QoS flow to data bearer for UL SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

Regarding the SDAP layer device, the terminal may receive a RRC message to set whether to use the header of the SDAP layer device or the function of the SDAP layer device for each PDCP layer device, each bearer, or each logical channel, and SDAP header is set, the 1-bit NAS QoS reflection setting indicator (NAS reflective QoS) and the 1-bit AS QoS reflection setting indicator (AS reflective QoS) of the SDAP header allow the UE to send uplink and downlink QoS flows and data bearer mapping information can be instructed to update or reset. The SDAP header may include QoS flow ID information indicating QoS. The QoS information may be used as data processing priority and scheduling information to support smooth service.

The main functions of the NR PDCP (S30, S65) may include some of the following functions.

- Header compression and decompression (ROHC only)

- Transfer of user data

- In-sequence delivery of upper layer PDUs

- Out-of-sequence delivery of upper layer PDUs

- PDCP PDU reordering for reception

- Duplicate detection of lower layer SDUs

- Retransmission of PDCP SDUs

- Ciphering and deciphering

- Timer-based SDU discard in uplink.

In the above, the reordering function of the NR PDCP device refers to a function of reordering PDCP PDUs received from a lower layer in order based on a PDCP SN (sequence number), and a function of transmitting data to an upper layer in the rearranged order can include Alternatively, the reordering function of the NR PDCP device may include a function of immediately forwarding without considering the order, and may include a function of reordering and recording lost PDCP PDUs, and the lost PDCP A function of reporting the status of PDUs to the transmitter may be included, and a function of requesting retransmission of lost PDCP PDUs may be included.

The main functions of the NR RLC (S35 and S60) may include some of the following functions.

- Transfer of upper layer PDUs

- In-sequence delivery of upper layer PDUs

- Out-of-sequence delivery of upper layer PDUs

- ARQ function (Error Correction through ARQ)

- Concatenation, segmentation and reassembly of RLC SDUs

- Re-segmentation of RLC data PDUs

- Reordering of RLC data PDUs

- Duplicate detection

- Error detection function (Protocol error detection)

- RLC SDU discard function (RLC SDU discard)

- RLC re-establishment

In-sequence delivery of the NR RLC device in the above means a function of sequentially delivering RLC SDUs received from a lower layer to an upper layer. The in-sequence delivery function of the NR RLC device may include a function of reassembling and transmitting the received RLC SDU when one RLC SDU is divided into several RLC SDUs, and transmits the received RLC PDUs It may include a function of reordering based on RLC sequence number (SN) or PDCP sequence number (SN), and may include a function of reordering and recording lost RLC PDUs. A function of reporting the status to the transmitter may be included, and a function of requesting retransmission of lost RLC PDUs may be included. In-sequence delivery of the NR RLC device may include, when there is a lost RLC SDU, a function of delivering only RLC SDUs prior to the lost RLC SDU to the upper layer in order, or Even if there are RLC SDUs, if a predetermined timer expires, a function of sequentially delivering all received RLC SDUs to an upper layer before the timer starts may be included. Alternatively, the in-sequence delivery function of the NR RLC device may include a function of sequentially delivering all RLC SDUs received up to now to a higher layer if a predetermined timer expires even if there is a lost RLC SDU. In addition, RLC PDUs may be processed in the order in which they are received (regardless of the order of serial numbers and sequence numbers, in the order of arrival) and delivered to the PDCP device regardless of order (out-of sequence delivery). In , segments stored in a buffer or to be received later may be received, reconstructed into one complete RLC PDU, processed, and transmitted to the PDCP device. The NR RLC layer may not include a concatenation function, and the function may be performed in the NR MAC layer or replaced with a multiplexing function of the NR MAC layer.

In the above, the out-of-sequence delivery function of the NR RLC device refers to a function of immediately delivering RLC SDUs received from a lower layer to an upper layer regardless of the order, and originally one RLC SDU is multiple RLC When received divided into SDUs, it may include a function of reassembling and forwarding them, and may include a function of storing RLC SNs or PDCP SNs of received RLC PDUs and arranging them in order to record lost RLC PDUs. can

The NR MACs (S40 and S55) may be connected to several NR RLC layer devices configured in one terminal, and the main functions of the NR MAC may include some of the following functions.

- Mapping between logical channels and transport channels

- Multiplexing/demultiplexing of MAC SDUs

- Scheduling information reporting

- HARQ function (Error correction through HARQ)

- Priority handling between logical channels of one UE

- Priority handling between UEs by means of dynamic scheduling

- MBMS service identification

- Transport format selection

- Padding function (Padding)

The NR PHY layer (S45, S50) channel-codes and modulates higher-layer data, transforms it into OFDM symbols and transmits it through a radio channel, or demodulates and channel-decodes OFDM symbols received through a radio channel to transmit to the higher layer. can be done

The detailed structure of the radio protocol structure may be variously changed according to a carrier (or cell) operation method. For example, when a base station transmits data to a terminal based on a single carrier (or cell), the base station and the terminal use a protocol structure having a single structure for each layer, such as S00. On the other hand, when the base station transmits data to the terminal based on CA (carrier aggregation) using multiple carriers in a single TRP, the base station and the terminal have a single structure up to RLC as in S10, but a protocol for multiplexing the PHY layer through the MAC layer structure will be used. As another example, when a base station transmits data to a terminal based on DC (dual connectivity) using multiple carriers in multiple TRPs, the base station and the terminal have a single structure up to RLC as in S20, but use the PHY layer through the MAC layer. A protocol structure for multiplexing is used.

Referring to the descriptions related to the PDCCH and beam configuration described above, it is difficult to achieve the required reliability in scenarios requiring high reliability such as URLLC because repetitive PDCCH transmission is not currently supported in Rel-15 and Rel-16 NRs. The present invention provides a method for repeatedly transmitting a PDCCH through multiple transmission points (TRPs) to improve PDCCH reception reliability of a terminal. Specific methods are specifically described in the following examples.

Hereinafter, embodiments of the present disclosure will be described in detail with accompanying drawings. The contents of this disclosure are applicable to FDD and TDD systems. Hereinafter, higher signaling (or higher layer signaling) in the present disclosure is a method of transmitting a signal from a base station to a terminal using a downlink data channel of a physical layer, or from a terminal to a base station using an uplink data channel of the physical layer, It may also be referred to as RRC signaling, PDCP signaling, or a medium access control (MAC) control element (MAC CE).

Hereinafter, in the present disclosure, in determining whether cooperative communication is applied, a PDCCH (s) allocated to a PDSCH to which cooperative communication is applied has a specific format, or a PDCCH (s) allocated to a PDSCH to which cooperative communication is applied is cooperative. Include a specific indicator indicating whether or not communication is applied, or PDCCH(s) allocating a PDSCH to which cooperative communication is applied are scrambled with a specific RNTI, or cooperative communication is assumed in a specific interval indicated by a higher layer, etc. It is possible to use various methods. For convenience of explanation, the terminal receiving the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as an NC-JT case.

Hereinafter, in the present disclosure, determining the priority between A and B means selecting a higher priority according to a predetermined priority rule and performing a corresponding operation or lower priority. It may be variously referred to as omitting or dropping an operation for.

Hereinafter, in the present disclosure, the above examples are described through a plurality of embodiments, but they are not independent, and one or more embodiments may be applied simultaneously or in combination.

[NC-JT related]

According to an embodiment of the present disclosure, Non-Coherent Joint Transmission (NC-JT) may be used for a UE to receive PDSCH from multiple TRPs.

The 5G wireless communication system can support not only services requiring high transmission rates, but also services with very short transmission delays and services requiring high connection density, unlike conventional ones. In a wireless communication network including multiple cells, transmission and reception points (TRPs), or beams, coordinated transmission between each cell, TRP or/and beam increases the strength of a signal received by a terminal or each cell , TRP or/and inter-beam interference control can be efficiently performed to satisfy various service requirements.

Joint Transmission (JT) is a typical transmission technology for the above-described cooperative communication, and transmits a signal to one UE through a plurality of different cells, TRPs, or/and beams, thereby transmitting the strength or throughput of the signal received by the UE. is a technique that increases At this time, the characteristics of the channel between each cell, TRP or / and beam and the terminal may be significantly different, and in particular, a channel supporting non-coherent precoding between each cell, TRP or / and beam In the case of non-coherent joint transmission (NC-JT), individual precoding, MCS, resource allocation, TCI indication, etc. are required according to channel characteristics for each cell, TRP or/and link between beams and UEs. can

The above-described NC-JT transmission includes a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), a physical uplink shared channel (PUSCH), and an uplink control channel. (PUCCH: physical uplink control channel) may be applied to at least one channel. During PDSCH transmission, transmission information such as precoding, MCS, resource allocation, and TCI is indicated as DL DCI, and for NC-JT transmission, the transmission information must be independently indicated for each cell, TRP or/and beam. This becomes a major factor in increasing a payload required for DL DCI transmission, which may adversely affect reception performance of a PDCCH transmitting DCI. Therefore, it is necessary to carefully design the tradeoff between DCI information amount and control information reception performance for JT support of PDSCH.

19 is a diagram illustrating an example of antenna port configuration and resource allocation for transmitting a PDSCH using cooperative communication in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 19, examples for PDSCH transmission are described for each technique of joint transmission (JT), and examples for allocating radio resources for each TRP are shown.

Referring to FIG. 19 , an example N000 for coherent joint transmission (C-JT) supporting coherent precoding between each cell, TRP or/and beam is shown.

In the case of C-JT, TRP A (N005) and TRP B (N010) transmit single data (PDSCH) to UE (N015), and joint precoding may be performed in multiple TRPs. This may mean that DMRS is transmitted through the same DMRS ports so that TRP A (N005) and TRP B (N010) transmit the same PDSCH. For example, each of TRP A (N005) and TRP B (N010) may transmit DRMS to the UE through DMRS port A and DMRS B. In this case, the terminal may receive one DCI information for receiving one PDSCH demodulated based on DMRS transmitted through DMRS port A and DMRS B.

19 is an example of non-coherent joint transmission (NC-JT, Non-Coherent Joint Transmission) supporting non-coherent precoding between each cell, TRP or / and beam for PDSCH transmission ( N020).

In the case of NC-JT, a PDSCH is transmitted to the terminal N035 for each cell, TRP or/and beam, and individual precoding may be applied to each PDSCH. Each cell, TRP or/and beam may transmit different PDSCHs or different PDSCH layers to the UE to improve throughput compared to transmission of a single cell, TRP or/and beam. In addition, each cell, TRP or / and beam repeatedly transmits the same PDSCH to the UE, thereby improving reliability compared to single cell, TRP or / and beam transmission. For convenience of description, a cell, a TRP, or/and a beam are collectively referred to as a TRP below.

At this time, if the frequency and time resources used by multiple TRPs for PDSCH transmission are the same (N040), if the frequency and time resources used by multiple TRPs do not overlap at all (N045), in multiple TRPs Various radio resource allocations may be considered, such as when some of the used frequency and time resources overlap (N050).

To support NC-JT, DCIs of various forms, structures, and relationships may be considered in order to simultaneously allocate a plurality of PDSCHs to one UE.

20 is a configuration of downlink control information (DCI) for NC-JT in which each TRP transmits a different PDSCH or a different PDSCH layer to a terminal in a wireless communication system according to an embodiment of the present disclosure. It is a drawing showing an example for

Referring to FIG. 20, case #1 (N100) is different from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to the serving TRP (TRP#0) used during single PDSCH transmission. In a situation where different (N-1) PDSCHs are transmitted, this is an example in which control information on PDSCHs transmitted in (N-1) additional TRPs is transmitted independently of control information about PDSCHs transmitted in serving TRPs. . That is, the terminal transmits control information on PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through independent DCIs (DCI#0 to DCI#(N-1)). can be obtained The formats of the independent DCIs may be the same or different, and the payloads of the DCIs may also be the same or different. In case #1 described above, each PDSCH control or allocation degree of freedom can be completely guaranteed, but when each DCI is transmitted in different TRPs, a coverage difference for each DCI may occur, resulting in deterioration of reception performance.

In case #2 (N105), in addition to the serving TRP (TRP#0) used in single PDSCH transmission, (N-1) additional TRPs (TRP#1 to TRP#(N-1)) In a situation where ) PDSCHs are transmitted, control information (DCI) for the PDSCHs of (N-1) additional TRPs is transmitted, and each of these DCIs is dependent on the control information for the PDSCHs transmitted from the serving TRP. see.

For example, in the case of DCI#0, which is control information for the PDSCH transmitted from the serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, but the cooperative TRP DCI format 1_0, It may include only some of the information elements of DCI format 1_1 and DCI format 1_2. Therefore, in the case of sDCI that transmits control information for PDSCHs transmitted from cooperative TRPs, compared to nDCI because the payload is smaller than normal DCI (nDCI) that transmits PDSCH-related control information transmitted from serving TRPs. Thus, it is possible to include reserved bits.

In case #2 described above, each PDSCH control or allocation degree of freedom may be limited according to the content of information elements included in sDCI. odds may be lower.

Case #3 (N110) is different (N-1) from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used during single PDSCH transmission. ) PDSCHs are transmitted, one control information for the PDSCHs of (N-1) additional TRPs is transmitted, and this DCI is dependent on the control information for the PDSCHs transmitted from the serving TRP.

For example, in the case of DCI#0, which is control information for the PDSCH transmitted from the serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, and the cooperative TRP In the case of control information for PDSCHs transmitted from TRP#1 to TRP#(N-1), only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 are used as one 'secondary' DCI ( sDCI) and can be transmitted. For example, the sDCI may include at least one of HARQ-related information such as frequency domain resource assignment, time domain resource assignment, and MCS of cooperative TRPs. In addition, information not included in sDCI, such as a bandwidth part (BWP) indicator or carrier indicator, may follow the DCI (DCI#0, normal DCI, nDCI) of the serving TRP.

In case #3 (N110), each PDSCH control or allocation degree of freedom may be limited according to the content of information elements included in sDCI, but reception performance of sDCI can be adjusted, and case #1 (N100) or case #2 Compared to (N105), complexity of DCI blind decoding of the terminal may be reduced.

Case #4 (N115) is different (N-1) from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to the serving TRP (TRP#0) used during single PDSCH transmission. In a situation where ) PDSCHs are transmitted, control information for PDSCHs transmitted from (N-1) additional TRPs is transmitted in the same DCI (Long DCI) as control information for PDSCHs transmitted from serving TRPs. This is an example. That is, the terminal can obtain control information on PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. In case # 4 (N115), the complexity of DCI blind decoding of the UE may not increase, but the degree of freedom in PDSCH control or allocation may be low, such as the number of cooperative TRPs being limited according to the long DCI payload limit.

In the following description and embodiments, sDCI may refer to various auxiliary DCIs, such as shortened DCI, secondary DCI, or normal DCI (DCI format 1_0 to 1_1 described above) including PDSCH control information transmitted from cooperative TRP, and has special restrictions. If not specified, the description is similarly applicable to the various auxiliary DCIs.

In the following descriptions and embodiments, cases of case #1 (N100), case #2 (N105), and case #3 (N110) in which one or more DCIs (PDCCH) are used to support NC-JT are multiple PDCCHs. It is divided into base NC-JT, and the case of the above-described case #4 (N115) in which a single DCI (PDCCH) is used to support NC-JT can be classified as a single PDCCH-based NC-JT. In multiple PDCCH-based PDSCH transmission, a CORESET in which DCI of serving TRP (TRP#0) is scheduled and a CORESET in which DCI of cooperative TRPs (TRP#1 to TRP#(N-1)) are scheduled can be distinguished. As a method for distinguishing CORESETs, there may be a method of distinguishing through an upper layer indicator for each CORESET, a method of distinguishing through beam setting for each CORESET, and the like. In addition, in the single PDCCH-based NC-JT, a single DCI schedules a single PDSCH having a plurality of layers instead of scheduling a plurality of PDSCHs, and the above-described plurality of layers can be transmitted from a plurality of TRPs. At this time, the connection relationship between the layer and the TRP transmitting the layer may be indicated through a transmission configuration indicator (TCI) indication for the layer.

In the embodiments of the present disclosure, "cooperative TRP" may be replaced with various terms such as "cooperative panel" or "cooperative beam" in actual application.

In the embodiments of the present disclosure, "when NC-JT is applied" means "when a UE simultaneously receives one or more PDSCHs in one BWP", "when a UE simultaneously transmits two or more TCIs (TCIs) in one BWP" It is possible to interpret variously according to the situation, such as "when the PDSCH is received based on the Configuration Indicator) indication" and "when the PDSCH received by the terminal is associated with one or more DMRS port groups". For convenience, one expression was used.

In the present invention, the radio protocol structure for NC-JT can be used in various ways according to TRP deployment scenarios. For example, even when there is no or small backhaul delay between cooperative TRPs, a method using a structure based on MAC layer multiplexing (CA-like method) similar to S10 of x4 is possible. On the other hand, when the backhaul delay between cooperative TRPs is too large to be ignored (for example, when information exchange between cooperative TRPs such as CSI, scheduling, and HARQ-ACK takes more than 2 ms), it is similar to S20 of x4. It is possible to obtain a robust characteristic against delay by using an independent structure for each TRP from the RLC layer (DC-like method).

A UE supporting C-JT/NC-JT may receive parameters or setting values related to C-JT/NC-JT from higher layer settings, and set RRC parameters of the UE based on this. For higher layer configuration, the UE may utilize a UE capability parameter, for example, tci-StatePDSCH. Here, the UE capability parameter, for example, tci-StatePDSCH, can define TCI states for the purpose of PDSCH transmission, and the number of TCI states is 4, 8, 16, 32, 64, 128 in FR1 and 64, 128 in FR2 , and among the set number, up to 8 states that can be indicated by the TCI field 3 bits of the DCI through the MAC CE message can be set. The maximum value of 128 means a value indicated by maxNumberConfiguredTCIstatesPerCC in the tci-StatePDSCH parameter included in capability signaling of the UE. As such, a series of configuration processes from higher layer configuration to MAC CE configuration may be applied to a beamforming instruction or a beamforming change command for at least one PDSCH in one TRP.

[Multi-DCI based Multi-TRP]

As an embodiment of the present disclosure, a multi-DCI based multi-TRP transmission method will be described. In the multi-DCI-based multi-TRP transmission method, a downlink control channel for NC-JT transmission may be set based on the Multi-PDCCH.

In NC-JT based on multiple PDCCHs, when DCI is transmitted for the PDSCH schedule of each TRP, it is possible to have a CORESET or search space classified for each TRP. CORESET or search space for each TRP can be set in at least one of the following cases.

* Higher layer index setting for each CORESET: CORESET setting information set as an upper layer may include an index value, and a TRP transmitting a PDCCH in the corresponding CORESET can be distinguished by the index value for each set CORESET. That is, in a set of CORESETs having the same higher layer index value, it may be considered that the same TRP transmits the PDCCH or the PDCCH scheduling the PDSCH of the same TRP is transmitted. The index for each CORESET described above may be named as CORESETPoolIndex, and it may be considered that the PDCCH is transmitted from the same TRP for CORESETs for which the same CORESETPoolIndex value is set. In the case of a CORESET in which the CORESETPoolIndex value is not set, it can be considered that the default value of CORESETPoolIndex is set, and the above-described default value may be 0.

- In the present disclosure, if the type of CORESETPoolIndex each of a plurality of CORESETs included in PDCCH-Config, which is higher layer signaling, exceeds one, that is, if each CORESET has a different CORESETPoolIndex, the UE determines that the base station is multi- It can be considered that a DCI-based multi-TRP transmission method can be used.

- Unlike this, in the present disclosure, if the type of CORESETPoolIndex each of a plurality of CORESETs included in PDCCH-Config, which is higher layer signaling, has one, that is, if all CORESETs have the same CORESETPoolIndex of 0 or 1, the terminal is a base station It can be regarded as transmission using single-TRP without using this multi-DCI based multi-TRP transmission method.

* Multiple PDCCH-Config settings: Multiple PDCCH-Configs are set in one BWP, and each PDCCH-Config may include PDCCH settings for each TRP. That is, a list of CORESETs for each TRP and/or a list of search spaces for each TRP can be configured in one PDCCH-Config, and one or more CORESETs and one or more search spaces included in one PDCCH-Config are considered to correspond to a specific TRP. can do.

* CORESET beam/beam group configuration: TRPs corresponding to the CORESETs can be distinguished through beams or beam groups set for each CORESET. For example, when the same TCI state is set in a plurality of CORESETs, it can be considered that the corresponding CORESETs are transmitted through the same TRP or a PDCCH scheduling the PDSCH of the same TRP is transmitted in the corresponding CORESET.

* Search space beam/beam group configuration: A beam or beam group is configured for each search space, and through this, TRPs for each search space can be distinguished. For example, when the same beam/beam group or TCI state is set in multiple search spaces, it can be considered that the same TRP transmits the PDCCH in the search space, or the PDCCH scheduling the PDSCH of the same TRP is transmitted in the search space. there is.

As described above, by classifying the CORESET or search space for each TRP, it is possible to classify PDSCH and HARQ-ACK information for each TRP, and through this, independent HARQ-ACK codebook generation and independent PUCCH resource use for each TRP are possible.

The above setting may be independent for each cell or each BWP. For example, while two different CORESETPoolIndex values are set for PCell, no CORESETPoolIndex value may be set for a specific SCell. In this case, it can be considered that NC-JT transmission is configured in the PCell, whereas NC-JT transmission is not configured in the SCell for which the CORESETPoolIndex value is not set.

The PDSCH TCI state activation/deactivation MAC-CE applicable to the multi-DCI based multi-TRP transmission method may follow FIG. 16. If the UE does not set the CORESETPoolIndex for each of all CORESETs in the upper layer signaling PDCCH-Config, the UE can ignore the CORESET Pool ID field (16-55) in the corresponding MAC-CE (16-50). If the UE can support the multi-DCI based multi-TRP transmission method, that is, if each CORESET in the upper layer signaling PDCCH-Config has a different CORESETPoolIndex, the UE can The TCI state in the DCI included in the PDCCH transmitted in CORESETs having the same CORESETPoolIndex value as the CORESET Pool ID field (16-55) value can be activated. For example, if the value of the CORESET Pool ID field (16-55) in the corresponding MAC-CE (16-50) is 0, the TCI state in the DCI included in PDCCHs transmitted from CORESETs with CORESETPoolIndex of 0 is Activation information can be followed.

When the terminal is configured to use the multi-DCI based multi-TRP transmission method from the base station, that is, when the number of CORESETPoolIndex types each of the plurality of CORESETs included in PDCCH-Config, which is higher layer signaling, exceeds one, or When each CORESET has a different CORESETPoolIndex, the UE can know that the following restrictions exist for PDSCHs scheduled from PDCCHs in each CORESET having two different CORESETPoolIndexes.

One) When PDSCHs indicated from PDCCHs in each CORESET having two different CORESETPoolIndexes completely or partially overlap, the UE can apply TCI states indicated from each PDCCH to different CDM groups, respectively. That is, two or more TCI states may not be applied to one CDM group.

2) When the PDSCH indicated from the PDCCH in each CORESET having two different CORESETPoolIndexes completely or partially overlaps, the UE determines the number of actual front loaded DMRS symbols, the actual number of additional DMRS symbols, the actual DMRS symbol location, and the DMRS type of each PDSCH. You can expect them not to be different.

3) The UE can expect that the bandwidth part indicated from the PDCCH in each CORESET having two different CORESETPoolIndex is the same and the subcarrier interval is also the same.

4) The UE can expect that each PDCCH fully includes information on PDSCHs scheduled from PDCCHs in each CORESET having two different CORESETPoolIndex.

[Single-DCI-based Multi-TRP]

As an embodiment of the present disclosure, a single-DCI based multi-TRP transmission method will be described. In the single-DCI-based multi-TRP transmission method, a downlink control channel for NC-JT transmission may be set based on a single-PDCCH.

In the single DCI-based multi-TRP transmission method, PDSCHs transmitted by multiple TRPs can be scheduled with one DCI. At this time, the number of TCI states may be used as a method of indicating the number of TRPs transmitting the corresponding PDSCH. That is, if the number of TCI states indicated in the DCI scheduling the PDSCH is two, it can be regarded as single PDCCH-based NC-JT transmission, and if the number of TCI states is one, it can be regarded as single-TRP transmission. The TCI states indicated by the above DCI can correspond to one or two TCI states among the TCI states activated by MAC-CE. If the TCI states of DCI correspond to the two TCI states activated by MAC-CE, the correspondence between the TCI codepoint indicated by DCI and the TCI states activated by MAC-CE is established, and the MAC corresponding to the TCI codepoint -This may be the case when there are two TCI states activated by CE.

As another example, if at least one codepoint among all codepoints of the TCI state field in DCI indicates two TCI states, the UE can consider that the base station can transmit based on the single-DCI based multi-TRP method. can At this time, at least one codepoint indicating two TCI states in the TCI state field may be activated through Enhanced PDSCH TCI state activation/deactivation MAC-CE.

21 is a diagram illustrating an Enhanced PDSCH TCI state activation/deactivation MAC-CE structure. The meaning of each field in the corresponding MAC CE and the values that can be set for each field are as follows.

- Serving Cell ID: This field indicates the identity of the Serving Cell for which the MAC CE applies. The length of the field is 5 bits. If the indicated Serving Cell is configured as part of a simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 as specified in TS 38.331 [5], this MAC CE applies to all the Serving Cells configured in the set simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 , respectively;

- BWP ID: This field indicates a DL BWP for which the MAC CE applies as the codepoint of the DCI bandwidth part indicator field as specified in TS 38.212 [9]. The length of the BWP ID field is 2 bits;

- C _i : This field indicates whether the octet containing TCI state ID _i,2 is present. If this field is set to "1", the octet containing TCI state ID _i,2 is present. If this field is set to "0", the octet containing TCI state ID _i,2 is not present;

- TCI state ID _i,j : This field indicates the TCI state identified by TCI-StateId as specified in TS 38.331 [5], where i is the index of the codepoint of the DCI Transmission configuration indication field as specified in TS 38.212 [9] ] and TCI state ID _i,j denotes the j-th TCI state indicated for the i-th codepoint in the DCI Transmission Configuration Indication field. The TCI codepoint to which the TCI States are mapped is determined by its ordinal position among all the TCI codepoints with sets of TCI state ID _i,j fields, ie the first TCI codepoint with TCI state ID _0,1 and TCI state ID _{0, 2} shall be mapped to the codepoint value 0, the second TCI codepoint with TCI state ID _1,1 and TCI state ID _1,2 shall be mapped to the codepoint value 1 and so on. The TCI state ID _i,2 is optional based on the indication of the Ci field. The maximum number of activated TCI codepoint is 8 and the maximum number of TCI states mapped to a TCI codepoint is 2.

- R : Reserved bit, set to "0".

In FIG. 21, if the value of the C ₀ field (21-05) is 1, the corresponding MAC-CE additionally adds the TCI state ID _0,2 field (21-15) to the TCI state ID _0,1 field (21-10). can include This means that TCI state ID _0,1 and TCI state ID _0,2 are activated for the 0th codepoint of the TCI state field included in DCI, and if the base station instructs the corresponding codepoint to the terminal, the terminal transmits two TCI states. can be instructed. If the value of the C ₀ field (21-05) is 0, the corresponding MAC-CE cannot include the TCI state ID _0,2 fields (21-15), which is the 0th codepoint of the TCI state field included in the DCI. It means that one TCI state corresponding to TCI state ID _0,1 is activated for

The above setting may be independent for each cell or each BWP. For example, a PCell may have up to two activated TCI states corresponding to one TCI codepoint, whereas a specific SCell may have up to one activated TCI states corresponding to one TCI codepoint. In this case, while NC-JT transmission is configured in the PCell, it can be considered that NC-JT transmission is not configured in the aforementioned SCell.

[Single-DCI-based Multi-TRP PDSCH repeated transmission scheme (TDM/FDM/SDM) identification method]

Next, the method of distinguishing the single-DCI-based multi-TRP PDSCH repeated transmission scheme is described. The UE may be instructed to use different single-DCI based multi-TRP PDSCH repeated transmission schemes (eg, TDM, FDM, SDM) according to the value indicated by the DCI field and higher layer signaling configuration from the base station. Table 41 below shows a method of distinguishing between single or multiple TRP-based techniques indicated to the terminal according to the value of a specific DCI field and higher layer signaling configuration.

Combination TCI state
Count CDM Group
Count RepetitionNumber setting and instruction condition Regarding repetitionScheme setting Transmission scheme instructed to the terminal One One ≥1 Condition 2 Not configured Single-TRP 2 One ≥1 Condition 2 Configured Single-TRP 3 One ≥1 Condition 3 Configured Single-TRP 4 One One Condition 1 Configured or not configured Single-TRP TDM scheme B 5 2 2 Condition 2 Not configured Multi-TRP SDM 6 2 2 Condition 3 Not configured Multi-TRP SDM 7 2 2 Condition 3 Configured Multi-TRP SDM 8 2 2 Condition 3 Configured Multi-TRP FDM scheme A/FDM scheme B/TDM scheme A 9 2 2 Condition 1 Not configured Multi-TRP TDM scheme B

In Table 41, each column can be explained as follows.

- Number of TCI states (column 2): This means the number of TCI states indicated by the TCI state field in DCI, and can be one or two.

- Number of CDM groups (column 3): This means the number of different CDM groups of DMRS ports indicated by the antenna port field in DCI. It can be 1, 2 or 3.

- Conditions for setting and indicating repetitionNumber (column 4): There are three conditions depending on whether or not the repetitionNumber is set for all TDRA entries that can be indicated by the Time Domain Resource Allocation field in the DCI and whether the actually indicated TDRA entry has the repetitionNumber setting. can

■ Condition 1: At least one of all TDRA entries that can be indicated by the Time Domain Resource Allocation field includes settings for repetitionNumber, and the TDRA entry indicated by the Time Domain Resource Allocation field in DCI includes settings for repetitionNumber greater than 1 if

■ Condition 2: When at least one of all TDRA entries that can be indicated by the Time Domain Resource Allocation field includes setting for repetitionNumber, and the TDRA entry indicated by Time Domain Resource Allocation field in DCI does not include setting for repetitionNumber

■ Condition 3: When all TDRA entries that can be indicated by the Time Domain Resource Allocation field do not include setting for repetitionNumber

- Related to repetitionScheme setting (column 5): This indicates whether to set repetitionScheme, which is higher layer signaling. RepetitionScheme, which is upper layer signaling, may be set to one of 'tdmSchemeA', 'fdmSchemeA', and 'fdmSchemeB'.

- Transmission scheme indicated to the UE (column 6): Means single or multiple TRP schemes indicated according to each combination (column 1) represented by Table 41 above.

■ Single-TRP: This means single TRP-based PDSCH transmission. If the UE has configured the pdsch-AggegationFactor in higher layer signaling PDSCH-config, the UE can be scheduled for repeated single TRP-based PDSCH transmission as many times as configured. Otherwise, the UE may be scheduled for single TRP-based PDSCH transmission.

■ Single-TRP TDM scheme B: refers to repeated PDSCH transmission based on time resource division between single TRP-based slots. According to Condition 1 related to repetitionNumber described above, the terminal repeatedly transmits the PDSCH in the time dimension as many times as the number of slots of repetitionNumber greater than 1 set in the TDRA entry indicated by the Time Domain Resource Allocation field. At this time, the same start symbol and symbol length of the PDSCH indicated by the TDRA entry are applied to each slot corresponding to the number of repetitionNumber times, and the same TCI state is applied to each repeated transmission of the PDSCH. This technique is similar to the slot aggregation method in that it performs repeated PDSCH transmission between slots on time resources, but is different from slot aggregation in that it can dynamically determine whether or not to indicate repeated transmission based on the Time Domain Resource Allocation field in the DCI. there is.

■ Multi-TRP SDM: Means a multi-TRP based spatial resource division PDSCH transmission method. This is a method of dividing and receiving layers from each TRP. Although it is not a repetitive transmission method, reliability of PDSCH transmission can be increased in that it can be transmitted by lowering the coding rate by increasing the number of layers. The UE may receive the PDSCH by applying the two TCI states indicated through the TCI state field in the DCI to each of the two CDM groups indicated by the base station.

■ Multi-TRP FDM scheme A: Multi-TRP-based frequency resource division PDSCH transmission method. It has one PDSCH transmission location, so it is not repetitive transmission like multi-TRP SDM, but it increases the amount of frequency resources and lowers the coding rate. It is a technique that can be transmitted with reliability. Multi-TRP FDM scheme A may apply two TCI states indicated through the TCI state field in DCI to frequency resources that do not overlap each other. If the PRB bundling size is determined to be wideband, the UE applies the first TCI state to the first ceil (N/2) RBs when the number of RBs indicated by the Frequency Domain Resource Allocation field is N, and the remaining floor (N/ 2) RBs apply and receive the second TCI state. Here, ceil(.) and floor(.) are operators that mean rounding up and rounding down to the first decimal place. If the PRB bundling size is determined to be 2 or 4, even-numbered PRGs apply the first TCI state, and odd-numbered PRGs receive the second TCI state.

■ Multi-TRP FDM scheme B: refers to a multiple TRP-based frequency resource division PDSCH repeated transmission method, and has two PDSCH transmission locations, so that PDSCHs can be repeatedly transmitted to each location. Similarly to A, Multi-TRP FDM scheme B may also apply two TCI states indicated through the TCI state field in DCI to frequency resources that do not overlap with each other. If the PRB bundling size is determined to be wideband, the UE applies the first TCI state to the first ceil (N/2) RBs when the number of RBs indicated by the Frequency Domain Resource Allocation field is N, and the remaining floor (N/ 2) RBs apply and receive the second TCI state. Here, ceil(.) and floor(.) are operators that mean rounding up and rounding down to the first decimal place. If the PRB bundling size is determined to be 2 or 4, even-numbered PRGs apply the first TCI state, and odd-numbered PRGs receive the second TCI state.

■ Multi-TRP TDM scheme A: Refers to a repeated PDSCH transmission scheme within a multi-TRP based time resource division slot. The terminal has two PDSCH transmission locations in one slot, and the first reception location may be determined based on the start symbol and symbol length of the PDSCH indicated through the Time Domain Resource Allocation field in DCI. The start symbol of the second reception position of the PDSCH may be a position obtained by applying a symbol offset as much as StartingSymbolOffsetK , which is higher layer signaling, from the last symbol of the first transmission position, and the transmission position may be determined by the indicated symbol length. If the upper layer signaling, StartingSymbolOffsetK , is not set, the symbol offset can be regarded as 0.

■ Multi-TRP TDM scheme B: Means a repeated PDSCH transmission scheme between multiple TRP-based time resource division slots. The UE has one PDSCH transmission location within one slot, and receives repeated transmission based on the start symbol and symbol length of the same PDSCH during slots as many times as the repetitionNumber times indicated through the Time Domain Resource Allocation field in DCI. can do. If repetitionNumber is 2, the UE may receive repeated PDSCH transmissions of the first and second slots by applying the first and second TCI states, respectively. If repetitionNumber is greater than 2, the terminal may use different TCI state application methods according to which tciMapping, which is higher layer signaling, is set. If tciMapping is set to cyclicMapping, the first and second TCI states are applied to the first and second PDSCH transmission positions, respectively, and the same TCI state application method is applied to the remaining PDSCH transmission positions. If tciMapping is set to sequentialMapping, the first TCI state is applied to the first and second PDSCH transmission positions, and the second TCI state is applied to the third and fourth PDSCH transmission positions. The same applies to the PDSCH transmission position.

[RLM RS related]

Next, the RLM RS selection or determination method when RLM RS (Radio Link Monitoring Reference Signal) is set or not set will be described. The terminal may receive a set of RLM RSs from the base station through RadioLinkMonitoringRS in RadioLinkMonitoringConfig, which is higher layer signaling for each downlink bandwidth part of SpCell, and a specific higher layer signaling structure may follow Table 42 below.

RadioLinkMonitoringConfig ::= SEQUENCE {
failureDetectionResourcesToAddModList SEQUENCE (SIZE(1..maxNrofFailureDetectionResources)) OF RadioLinkMonitoringRS OPTIONAL, -- Need N
failureDetectionResourcesToReleaseList SEQUENCE (SIZE(1..maxNrofFailureDetectionResources)) OF RadioLinkMonitoringRS-Id OPTIONAL, -- Need N
beamFailureInstanceMaxCount ENUMERATED {n1, n2, n3, n4, n5, n6, n8, n10} OPTIONAL, -- Need R
beamFailureDetectionTimer ENUMERATED {pbfd1, pbfd2, pbfd3, pbfd4, pbfd5, pbfd6, pbfd8, pbfd10} OPTIONAL, -- Need R
...
}

RadioLinkMonitoringRS ::= SEQUENCE {
radioLinkMonitoringRS-Id RadioLinkMonitoringRS-Id,
purpose ENUMERATED {beamFailure, rlf, both},
detectionResource CHOICE {
ssb-Index SSB-Index,
csi-RS-Index NZP-CSI-RS-ResourceId
},
...
}

Table 43 below may indicate the set or selectable number of RLM RSs for each specific purpose according to the maximum number of SSBs per half frame (L _max ). As shown in Table 43 below, N _LR-RLM RSs can be used for link recovery or radio link monitoring according to the L _max value, and N _RLMs among the N _LR-RLM RSs can be used for radio link monitoring.

If the UE does not receive higher layer signaling, RadioLinkMonitoringRS, and the UE sets the TCI state for receiving the PDCCH in the control resource set, and at least one CSI-RS is included in the TCI state, the following RLM RS selection method RLM RS can be selected by following them.

- RLM RS selection method 1) If an activated TCI state to be used for PDCCH reception has one reference RS (ie, one activated TCI state has only one of QCL-TypeA, B, or C), UE may select a reference RS of an activated TCI state to be used for PDCCH reception as an RLM RS.

- RLM RS selection method 2) If the activated TCI state to be used for PDCCH reception has two reference RSs (ie, one activated TCI state has one of QCL-TypeA, B, or C and QCL-TypeD ), the UE may select the RLM-RS as the reference RS of QCL-TypeD. The terminal does not expect two QCL-TypeDs to be set in one activated TCI state.)

- RLM RS Selection Method 3) The UE does not expect an aperiodic or semi-persistent RS to be selected as the RLM RS.

- RLM RS selection method 4) When L _max = 4, the UE can select N _RLM RSs (since L _max is 4, two can be selected). The RLM RS is selected based on the RLM RS selection methods 1 to 3, among the reference RSs of the TCI state set in the control resource set for PDCCH reception, and the shorter the period of the search space to which the control resource set is connected, the higher the Based on the priority, the RLM RS is selected from the reference RS of the TCI state set in the control resource set connected to the search space of the shortest cycle. If there are a plurality of control resource sets connected to a plurality of search spaces having the same period, RLM RS selection is performed from the reference RS of the TCI state set to the higher control resource set index.

22 is a diagram illustrating an RLM RS selection process according to an embodiment of the present disclosure. This figure shows control resource set #1 to control resource set #3 (22-01 to 22-04) connected to search space #1 to search space #4 (22-01 to 22-04) having different cycles within the activated downlink bandwidth part. 05 to 22-07) and the reference RS of the TCI state set in each control resource set. Based on the RLM RS selection method 4, RLM RS selection uses the TCI state set in the control resource set connected to the search space of the shortest period, but search space #1 (22-01) and search space #3 (22-01). 03), the reference of the TCI state set in control resource set #2 having the higher index among control resource set #1 (22-05) and control resource set #2 (22-06) connected to each search space. RS can be used as the highest priority in RLM RS selection. In addition, since the TCI state set in control resource set #2 has only QCL-TypeA and the corresponding reference RS is a periodic RS, P CSI-RS #2 (22-10) by the RLM RS selection methods 1 and 3 may be selected as the first RLM RS. Next, the reference RS of QCL-TypeD can be a selection candidate by the RLM RS selection method 2 among the reference RSs of the TCI state set in the control resource set #1 having priority, but the corresponding RS is semi-persistent Since it is an RS (22-09), it is not selected as an RLM RS by the RLM RS selection method 3 above. Therefore, reference RSs of TCI state set in control resource set #3 can be considered as the next priority, and by the RLM RS selection method 2, the reference RS of QCL-TypeD can be a selection candidate, and the reference RS can be selected periodically. Since it is a (periodic) RS, P CSI-RS#4 (22-12) can be selected as the second RLM RS by the RLM RS selection method 3. Accordingly, the finally selected RLM RS may be P CSI-RS#2 or P CSI-RS#4 (22-13).

[Related to channel status measurement and reporting method]

Next, a method for measuring and reporting channel conditions in a 5G communication system will be described in detail.

Channel state information (CSI) includes channel quality information (CQI), precoding matrix index (PMI), CSI-RS resource indicator (CSI-RS resource indicator, CRI), SS / PBCH block resource indicator (SS / PBCH block resource indicator, SSBRI), layer indicator (layer indicator, LI), rank indicator (rank indicator, RI), and / or L1-RSRP (Reference Signal Received Power), etc. May be included there is. The base station may control time and frequency resources for the aforementioned CSI measurement and reporting of the terminal.

For the aforementioned CSI measurement and reporting, the UE provides setting information (CSI-ReportConfig) for N (≥1) CSI reports and setting information (CSI-ResourceConfig) for M (≥1) RS transmission resources. , One or two trigger states (CSI-AperiodicTriggerStateList, CSI-SemiPersistentOnPUSCH-TriggerStateList) list information can be set through higher layer signaling.

Setting information for the aforementioned CSI measurement and reporting may be as follows described in Tables 44 to 50 in more detail.

Table 44 shows an example of CSI-ReportConfig IE and related parameter descriptions.

Table 45 shows an example of CSI-ResourceConfig IE and related parameter descriptions.

Table 46 shows an example of NZP-CSI-RS-ResourceSet IE and related parameter descriptions.

Table 47 shows an example of the CSI-SSB-ResourceSet IE.

Table 48 shows an example of CSI-IM-ResourceSet IE.

Table 49 shows an example of CSI-AperiodicTriggerStateList IE and related parameter descriptions.

Table 50 shows an example of CSI-SemiPersistentOnPUSCH-TriggerStateList IE and related parameter descriptions.

Regarding the aforementioned CSI report setting ( CSI-ReportConfig ), each report setting CSI-ReportConfig may be associated with one or more CSI resource settings, that is, CSI-ResourceConfig. The association between CSI report setting and CSI resource setting may be indicated by the following parameters in CSI-ReportConfig.

- carrier: Indicates a cell/component carrier (CC) to which the CSI resource setting associated with the CSI reporting setting belongs

- resourcesForChannelMeasurement: Indicates CSI resource settings for channel measurement associated with CSI reporting settings

- csi-IM-ResourcesForInterference: Indicates CSI resource setting composed of CSI-IM resources for interference measurement associated with CSI reporting setting

- nzp-CSI-RS-ResourcesForInterference: Indicates CSI resource setting composed of CSI-RS resources for interference measurement associated with CSI reporting setting. Each port of the CSI-RS resource belonging to this CSI resource setting may be precoded or beamformed to point to a separate interference transmission layer.

The terminal may perform CSI reporting based on the channel state information measured by the CSI-RS or CSI-IM resource in the associated CSI resource setting according to the above relationship.

As a time domain reporting operation for each report setting CSI-ReportConfig, 'Aperiodic', 'Semi-Persistent', and 'Periodic' methods are supported, which depend on the reportConfigType parameter set from the upper layer. It can be configured from the base station to the terminal by Depending on the time domain reporting operation, the type of uplink resource to which the CSI report is to be transmitted may be determined. Aperiodic CSI reporting of the UE is performed using PUSCH, periodic CSI reporting is performed using PUCCH, and semi-persistent CSI reporting is 'PUCCH-based semi-persistent OnPUCCH' or 'PUSCH-based semi-persistent OnPUSCH' report. can be supported. When the semi-permanent CSI report is triggered or activated by DCI, the report is performed using PUSCH, and when activated by MAC control element (MAC CE), the report uses PUCCH. can be performed using In the case of a periodic or semi-permanent CSI reporting method, a UE may receive a PUCCH or PUSCH resource to transmit CSI from a base station through higher layer signaling. The period and slot offset of the PUCCH or PUSCH resource to transmit CSI may be given based on the numerology of the uplink (UL) partial bandwidth configured to transmit the CSI report. In the case of the aperiodic CSI reporting method, the UE may receive scheduling of PUSCH resources to transmit CSI from the base station through L1 signaling (DCI, for example, DCI format 0_1 described above).

Regarding the aforementioned CSI resource setting ( CSI-ResourceConfig ), each CSI resource setting CSI-ReportConfig may include S (≥1) CSI resource sets (set by higher layer parameter csi-RS-ResourceSetList). The CSI resource set list may consist of a non-zero power (NZP) CSI-RS resource set and an SS/PBCH block set or a CSI-interference measurement (CSI-IM) resource set. can Each CSI resource setting may be located in a downlink (DL) partial bandwidth identified by an upper layer parameter bwp-id. The time domain operation of the CSI-RS resource in the CSI resource setting may be set to one of 'aperiodic', 'periodic' or 'semi-permanent' from the upper layer parameter resourceType. For periodic or semi-permanent CSI resource setting, the number of CSI-RS resource sets may be limited to S = 1, and the configured period and slot offset may be given based on the numerology of the downlink partial bandwidth identified by bwp-id. there is.

There is a restriction on mutual time domain operation between the CSI reporting setting and the CSI resource setting associated therewith. For example, it is not possible to associate a CSI resource setting configured aperiodically with a CSI reporting setting configured periodically. The combination of supported CSI reporting settings and CSI resource settings can be based on Table 51 below.

Aperiodic CSI reporting can be triggered by the "CSI request" indicator field of the aforementioned DCI format 0_1 or 0_2 corresponding to the scheduling DCI for the PUSCH. The UE can monitor the PDCCH, obtain control information conforming to DCI format 0_1 or 0_2, and obtain scheduling information for PUSCH and a CSI request indicator from the corresponding control information. The CSI request indicator may be set to N _TS (= 0, 1, 2, 3, 4, 5, or 6) bits, and the number of bits of the CSI request indicator may be determined by higher layer signaling (reportTriggerSize). The CSI request indicator field is mapped to one trigger state, and the mapping between the indicator field and the trigger state may be indicated by an upper layer parameter CSI-AperiodicTriggerStateList. Each trigger state may indicate one aperiodic CSI reporting setting and one CSI resource set within the associated CSI resource setting. The purpose of indicating the CSI resource set is to indicate which CSI resource set to perform CSI reporting on, if the number of two or more CSI resource sets belongs to the CSI resource setting.

Meanwhile, a case in which the number of fields of the CSI request indicator and the number of trigger states of the upper layer parameter CSI-AperiodicTriggerStateList may not match may occur. The interpretation of the CSI request indicator for this may be as follows.

- When the CSI request indicator indicates 0 (all bit values are 0), it may mean that CSI reporting is not requested.

-If the number of CSI trigger states (M) in the configured CSI-AperiodicTriggerStateList is greater than 2 ^NTs -1, M CSI trigger states can be mapped to 2 ^NTs -1 according to a predefined mapping relationship, and 2 One of the trigger states of ^NTs -1 may be indicated by the CSI request field.

- If the number (M) of CSI trigger states in the configured CSI-AperiodicTriggerStateList is less than or equal to 2 ^NTs -1, one of the M CSI trigger states may be indicated in the CSI request field.

[Table 52] below shows an example of a relationship between a CSI request indicator and a CSI trigger state that may be indicated by the corresponding indicator.

The UE may perform measurement on the CSI resource in the CSI trigger state triggered by the CSI request field, and from this CSI (at least one or more of the aforementioned CQI, PMI, CRI, SSBRI, LI, RI, or L1-RSRP) including) can be created. The UE may transmit the acquired CSI using the PUSCH scheduled by the corresponding DCI format 0_1. When 1 bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 indicates "1", uplink data (UL-SCH) and acquired CSI are transmitted to PUSCH resources scheduled by DCI format 0_1 It can be transmitted by multiplexing. When 1 bit corresponding to the uplink data indicator (UL-SCH indicator) in DCI format 0_1 indicates “0”, mapping only CSI without uplink data (UL-SCH) to PUSCH resources scheduled by DCI format 0_1 can transmit

Through the above-described downlink reception operation of the NR. The terminal may receive higher layer signaling related to the TCI state for PDSCH reception from the base station for each BWP, and may activate some of them for each codepoint of the TCI state field in the DCI through the MAC-CE, and finally, the PDSCH Beam-related information to be used for reception may be instructed through the TCI state field in the DCI. In addition, the terminal can use some of the beam-related information to be used for PDSCH reception from the base station as a TCI state for PDCCH reception, and can receive corresponding higher layer signaling for each BWP, and one of the TCI states is MAC-CE You can use the method of activating with the TCI state of the control resource set through In addition, transmission beam related information to be used during PUSCH transmission can be instructed through the SRI field in DCI, can be identified through SRS spatial relation info set as higher layer signaling in the SRS resource indicated through the SRI field, and can be used during PUCCH transmission. Tx beam related information may be indicated through a MAC-CE that activates a connection between PUCCH spatial relation and PUCCH resource set by higher layer signaling.

As such, in 5G NR, information on a plurality of transmission and reception beams configured by higher layer signaling to the UE and a method of quasi-statically or dynamically activating and instructing the UE are defined. These predefined methods support transmission and reception beam indication in very sophisticated units. When the base station and the terminal have the same understanding, or due to a situation in which the terminal proceeds on a predetermined path from a specific starting point to a destination point, the base station and the terminal know in advance information about the transmission/reception beam to be used at all times during the route. If there is, or if it is possible to predict the transmission/reception beam by implementing the base station and the terminal, the terminal may not need to exchange information about the dynamic transmission/reception beam with the base station. For example, when a terminal is located on a high-speed railway running on a fixed main road, information on transmission/reception beams of the terminal may be determined according to the speed of the railway and the type of beam used by base stations located near the track. As another example, when a terminal is located in a drone taxi or an autonomous vehicle moving along a very fixed path, there is a high possibility of using a fixed transmit/receive beam change pattern. In addition, in the case of a terminal that exists in a fixed location and does not have mobility, such as customer premise equipment (CPE), it is possible to change the type of transmission and reception beams according to a specific pattern with a plurality of communicable base stations. For such a use case, the terminal may be able to operate based on relatively simple transmission/reception beam configuration and instruction rather than highly sophisticated and dynamic signaling defined in the above-described NR for transmission/reception beam application/instruction/activation operations.

Based on such an example, the present invention relates to a method and apparatus for transmitting/receiving data and control information based on predicted transmission configuration information (TCI) in a wireless communication system. As a conventional method of receiving downlink data information, a UE is instructed to perform down-selection using a MAC-CE and a downlink control channel from transmission configuration information set by higher layer signaling, and can receive downlink data information using this there is. In this case, the number of sets of information that can be indicated using the downlink control channel may be limited to a maximum of eight. Meanwhile, in a scenario in which a terminal having an advanced transceiver performs a very fixed route, it may be assumed that the base station and the terminal can predict TCI information received from the base station in advance according to time. For such a terminal, the base station may apply a plurality of preset TCI information for each time period to use for downlink data information reception instead of a dynamic TCI indication each time. Additionally, in the present invention, not only TCI information but also other setting or indication information (e.g., MCS, TDRA, FDRA, TPC, etc.) .

For convenience in the following description of the present disclosure, cells, transmission points, panels, beams, or transmission points that can be distinguished through higher layer/L1 parameters such as TCI state or spatial relation information or indicators such as cell ID, TRP ID, or panel ID / and the transmission direction are unified and described as a transmission reception point (TRP). Therefore, in actual application, TRP can be appropriately replaced with one of the above terms.

Hereinafter, in the present disclosure, in determining whether cooperative communication is applied, a PDCCH (s) allocated to a PDSCH to which cooperative communication is applied has a specific format, or a PDCCH (s) allocated to a PDSCH to which cooperative communication is applied is cooperative. Include a specific indicator indicating whether or not communication is applied, or PDCCH(s) allocating a PDSCH to which cooperative communication is applied are scrambled with a specific RNTI, or cooperative communication is assumed in a specific interval indicated by a higher layer, etc. It is possible to use various methods. For convenience of explanation, the terminal receiving the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as an NC-JT case.

Hereinafter, embodiments of the present disclosure will be described in detail with accompanying drawings. Hereinafter, a base station is a subject that performs resource allocation of a terminal, and may be at least one of a gNode B, a gNB, an eNode B, a Node B, a base station (BS), a radio access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing communication functions. Hereinafter, an embodiment of the present disclosure is described using a 5G system as an example, but the embodiment of the present disclosure can be applied to other communication systems having a similar technical background or channel type. For example, LTE or LTE-A mobile communication and mobile communication technology developed after 5G may be included in this. Accordingly, the embodiments of the present disclosure may be applied to other communication systems through some modification without significantly departing from the scope of the present disclosure as determined by a person skilled in the art. The contents of this disclosure are applicable to FDD and TDD systems.

In addition, in describing the present disclosure, if it is determined that a detailed description of a related function or configuration may unnecessarily obscure the gist of the present disclosure, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present disclosure, which may vary according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, in describing the present disclosure, higher layer signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

- MIB (Master Information Block)

- SIB (System Information Block) or SIB X (X=1, 2, ...)

- Radio Resource Control (RRC)

- MAC (Medium Access Control) CE (Control Element)

Also, L1 signaling may be signaling corresponding to at least one or a combination of one or more of signaling methods using the following physical layer channels or signaling.

- PDCCH (Physical Downlink Control Channel)

- Downlink Control Information (DCI)

- UE-specific DCI

- Group common DCI

- Common DCI

- Scheduling DCI (eg DCI used for the purpose of scheduling downlink or uplink data)

- Non-scheduling DCI (eg, a DCI that is not intended to schedule downlink or uplink data)

- PUCCH (Physical Uplink Control Channel)

- UCI (Uplink Control Information)

Hereinafter, in the present disclosure, determining the priority between A and B means selecting a higher priority according to a predetermined priority rule and performing a corresponding operation or lower priority. It may be variously referred to as omitting or dropping an operation for.

Hereinafter, in the present disclosure, the above examples are described through a plurality of embodiments, but they are not independent, and one or more embodiments may be applied simultaneously or in combination.

<First Embodiment: Control method based on presetting of transmit/receive beam to be applied to specific transmit/receive channel/signal>

As an embodiment of the present disclosure, a preset-based control scheme of a transmit/receive beam to be applied to a specific transmit/receive channel/signal will be described. In 5G NR, the terminal can receive information on up to 128 TCI states through higher layer signaling, and up to 8 TCI states among them can be activated for each codepoint of the TCI state field in DCI based on MAC-CE Finally, one TCI state out of up to eight can be indicated based on the DCI. Based on such two-step adjustment and selection of the number of candidates, overhead can be reduced in the case of DCI-based dynamic TCI state indication. However, when using this method, the terminal may have a disadvantage in that it cannot fully use the defined 128 TCI states due to reduced overhead. In addition, if the base station and the terminal can predict and know the change of the TCI state over time, the dynamic TCI state indication can force the terminal to perform unnecessary PDCCH decoding, and the overhead for the TCI state field in the DCI can be a waste Therefore, unlike the two-step candidate number adjustment and selection method based on higher layer signaling, MAC-CE, and DCI described above, a method of automatically applying the transmission and reception beams of the terminal according to the order of preset TCI states can be considered. there is. For convenience, when each method is referred to later, the two-step candidate number adjustment and selection method based on higher layer signaling, MAC-CE, and DCI described above is [Method 1], transmission/reception to be applied to a specific transmission/reception channel/signal. The beam preset-based control method can be named [Method 2].

For [Method 2], the terminal may receive a list of a plurality of TCI states from the base station and a time to apply each TCI state. Corresponding higher layer signaling may have the following configuration information structure.

Pre-configured-TCI-state-list ::= SEQUENCE {

pre-configured-TCI-state-list SEQUENCE (SIZE (1, ..., maxNrofPreConfiguredTCIState)) OF TCI-StateId,

appliedTime-list SEQUENCE(SIZE(1, ..., maxNrofPreConfiguredTCIState)) OF appliedTime

}

In the upper layer signaling structure, pre-configured-TCI-state-list is higher-layer signaling meaning the order of the plurality of TCI states described above, and appliedTime-list is set in the pre-configured-TCI-state-list It is higher layer signaling that means the application holding time of each TCI state that exists, and maxNrofPreConfiguredTCIState may be higher layer signaling that means the maximum number of a plurality of TCI states that can be set in this way. That is, during the first appliedTime in the appliedTime-list, a downlink signal is received using the first TCI-StateId in the pre-configured-TCI-state-list, and after the first appliedTime has elapsed, the appliedTime During the second appliedTime in -list, a downlink signal can be received using the second TCI-StateId in the pre-configured-TCI-state-list.

According to an embodiment, if the UE is configured for the higher layer signaling, instead of using [Method 1], the UE is in the TCI state defined by TCI-StateId for a specific time defined by appliedTime according to the configuration. It is possible to receive a downlink signal based on. At this time, if the downlink signal is received using the last TCI-StateId in the pre-configured-TCI-state-list during the last appliedTime in the appliedTime-list, the same method is performed again from the first appliedTime and TCI-StateId. can be repeated.

According to an embodiment, if the UE is configured for the higher layer signaling, the UE can select between the [Method 1] and the [Method 2] based on a specific MAC-CE. If the UE receives the MAC-CE that activates [Method 2], the UE receives the last symbol of the PUCCH transmission including HARQ-ACK information indicating whether the PDSCH including the corresponding MAC-CE is successfully received. [Method 2] can be used from the time point after 3 ms. At this time, if the downlink signal is received using the last TCI-StateId in the pre-configured-TCI-state-list during the last appliedTime in the appliedTime-list, the [Method 2] is not used and the [Method 2] is not used. 1], transmit/receive beam control may be performed. Alternatively, until the terminal receives the MAC-CE indicating deactivation for the [Method 2], if the last TCI in the pre-configured-TCI-state-list during the last appliedTime in the appliedTime-list - After receiving the downlink signal using StateId, the same method can be repeated again from the first appliedTime and TCI-StateId. The activation method for the above-described MAC-CE based [Method 2] may also be possible through DCI, and using DCI format 1_1 or 1_2, when specific fields in DCI have specific values as follows, it may mean activation or inactivation. there is.

- DCI format 1_1 or 1_2 with CRC scrambled as CS-RNTI or new RNTI

- All bits allocated to RV (Redundancy Version) field and MCS (Modulation and Coding Scheme) field have 1

- Regarding the Frequency Domain Resource Allocation (FDRA) field

■ When the frequency resource allocation method is set to Type 0 or dynamicSwitch, all bits allocated to the FDRA field have 0

■ When the frequency resource allocation method is set to Type 1, all bits allocated to the FDRA field have 1

- All bits assigned to the HARQ Process Number field have 0

- If all bits assigned to the NDI (New Data Indicator) field have 0, they are active, and if they are 1, they are inactive.

Higher layer signaling for [Method 2] may exist in various forms as follows.

According to an embodiment, there is one higher layer signaling for [Method 2], and the higher layer signaling for [Method 2] can be applied only to transmission/reception beam control for the PDSCH. At this time, the remaining downlink channels/signals such as PDCCH or CSI-RS may operate according to existing methods. That is, a MAC-CE based TCI state activation method may be used for the PDCCH, and a TCI state configured by higher layer signaling may be used for the CSI-RS. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 2], and the higher layer signaling for [Method 2] can be applied only to transmission/reception beam control for PDCCH and PDSCH. That is, the same Rx beams can be used for downlink control and data channels, and in the case of a PDCCH, it can be applied to all control resource sets connected to a common search space and a UE-specific search space. At this time, the TCI state set by higher layer signaling may be used in the CSI-RS as in the conventional method. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 2], and the higher layer signaling for [Method 2] can be applied only to transmission/reception beam control for PDCCH and PDSCH. That is, the same Rx beams for downlink control and data channels may be used. In particular, in the case of PDCCH, unlike the above, it can be applied only to a control resource set connected only to a UE-specific search space. If a certain control resource set is connected to both the common search space and the terminal-specific search space, transmission/reception beam control may be performed based on [Method 1]. At this time, the TCI state set by higher layer signaling may be used in the CSI-RS as in the conventional method. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 2], and higher layer signaling for [Method 2] can be applied to PDCCH, PDSCH, and CSI-RS excluding SSB and TRS. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 2], higher layer signaling for [Method 2] is applied to PDCCH and PDSCH excluding SSB and TRS, and in case of CSI-RS, specific CSI -Applicable only when higher layer signaling, which has meaning about whether [Method 2] is applied to RS resources, is set, or has meaning about whether [Method 2] is applied only to aperiodic CSI-RS resources It can be applied without higher layer signaling. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals. As another method for the uplink transmission/reception beam, the terminal may apply one set higher layer signaling to the uplink transmission/reception beam as well. In this case, applying the TCI-State to the Tx beam of the UE may mean that the UE determines the uplink Tx beam based on the QCL-TypeD reference RS set in the TCI-State.

According to an embodiment, there are two higher layer signaling for [Method 2], and each can be used for downlink and uplink transmission/reception beam control. Similar to the various methods applied to downlink channels/signals as described above for higher layer signaling to be used for downlink transmission/reception beam control, higher layer signaling to be used for uplink transmission/reception beam control among PUSCH, PUCCH, SRS, and PRACH Whether to apply to some or all of them may be standardly defined, or it may operate based on higher layer signaling settings having a meaning of whether to apply [Method 2] within resource settings for each uplink channel/signal. For example, [Method 2] is applicable to all PUSCH transmissions and UE-specific PUCCH resources, and an existing method can be used for SRS and PRACH.

According to an embodiment, when defining the UE capability report for [Method 2], the UE may consider at least one of the following.

- [Method 2] The number of higher layer signaling that can be configured in the terminal when supported

- [Method 2] Range of downlink channels/signals applied when supported

- [Method 2] Range of uplink channels/signals applied when supported

- How to select between [Method 1] and [Method 2]: A supported method among RRC, MAC-CE, and DCI-based methods

- [Method 2] If supported, the maximum number of configurable transmit/receive beams (maxNrofPreConfiguredTCIState above)

23 is a diagram illustrating a preset-based control scheme of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure.

In this figure, it can be assumed that the terminal operates based on MAC-CE for the selection method among [Method 1] and [Method 2]. In addition, in the figure, it is assumed that the terminal receives one higher layer signaling for the [Method 2] and applies the higher layer signaling to all downlink and uplink channels/signals except SSB and TRS. can In addition, in this figure, it can be assumed that the terminal receives settings for higher layer signaling from the base station as in (23-22).

The terminal may receive a DCI for scheduling a PDSCH including a MAC-CE indicating activation of [Method 2] from the base station (23-00), and upon receiving the DCI, the corresponding DCI is received based on [Method 1] It can be assumed that TCI-State#1 is activated for the control resource set to be used (23-03). For example, it can be assumed that TCI-state#1 is activated by PDCCH TCI state activation MAC-CE received 3 ms before DCI (23-00) reception. The terminal may receive a PDSCH including a MAC-CE indicating activation of [Method 2] based on the corresponding DCI from the base station (23-01), and when receiving the PDSCH, based on [Method 1], the TCI-State It can be assumed that #2 is instructed (23-04). For example, it can be assumed that TCI-State#2 is indicated by DCI (23-00). Thereafter, the terminal may transmit to the base station a PUCCH including HARQ-ACK information indicating whether reception of a PDSCH including a MAC-CE indicating activation of [Method 2] is successful (23-02), and when transmitting the PUCCH Based on [Method 1], it can be assumed that pucch-spatialRelationInfo#1 connected to the corresponding PUCCH resource is used (23-05). If the UE succeeds in receiving the PDSCH including the MAC-CE and transmits the ACK information through the PUCCH, the UE's transmit/receive beam The control method can be operated based on [Method 1], and from the time point (23-06) after 3 ms after PUCCH transmission (23-08), the UE transmit/receive beam control method is based on [Method 2] can be operated. From the point in time (23-06) after 3 ms after PUCCH transmission, the UE operates all downlinks and uplinks except for SSB and TRS as described above during appliedTime#1, which is higher layer signaling (23-08). For channels/signals, TCI-State#1 can be used as a transmit/receive beam (23-12). That is, the reception beam for the DCI (23-09) received by the UE during appliedTime#1 and the PDSCH (23-10) scheduled by the corresponding DCI may be determined as TCI-State#1. As described above, the UE receives TCI for all downlink and uplink channels/signals except for SSB and TRS during appliedTime#2 (23-18) from the point at which appliedTime#1 ends (23-13) and later (23-15). -State#4 can be used as a transmit/receive beam (23-18). That is, the reception beam for the DCI (23-16) received by the UE during appliedTime#2 and the PDSCH (23-17) scheduled by the corresponding DCI can be determined as TCI-State#4. Similarly, from the point at which appliedTime#2 ends (23-19), the terminal may perform transmit/receive beam control using the set TCI-State for a set time similar to the above (23-21).

24 is a diagram illustrating an operation of a base station for a preset-based control method of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure. The base station may receive a terminal capability report from the terminal (2400). At this time, the information that the base station can receive may include at least one of the terminal capability reports. Thereafter, the base station may transmit configuration information related to transmission/reception beams to the terminal by referring to the terminal capability report (2401). Thereafter, the base station can perform transmission/reception beam control operation of the terminal using [Method 2] when a specific condition is satisfied (2402), and when the specific condition is not satisfied (2402) [Method 1] is used. can Possible conditions at this time are when upper layer signaling is set for [Method 2] as described above, when MAC-CE indicating activation for using [Method 2] is received, or when DCI is received can be

25 is a diagram illustrating an operation of a terminal in relation to a preset based control method of a transmission/reception beam to be applied to a specific transmission/reception channel/signal according to an embodiment of the present disclosure. The terminal may transmit a terminal capability report to the base station (2500). At this time, the information that the base station can receive may include at least one of the terminal capability reports. Thereafter, the terminal may transmit configuration information related to transmission/reception beams from the base station (2501). Thereafter, when a specific condition is satisfied (2502), the terminal can perform transmission/reception beam control operations when receiving downlink from the base station and transmitting uplink to the base station using [Method 2] (2504), and the specific condition is satisfied. If not, (2502) [Method 1] can be used. Possible conditions at this time are when upper layer signaling is set for [Method 2] as described above, when MAC-CE indicating activation for using [Method 2] is received, or when DCI is received can be

<Second Embodiment: TCI candidate presetting and indication-based transmit/receive beam control method>

As an embodiment of the present disclosure, a TCI candidate presetting method and an indication-based transmit/receive beam control method will be described. The problem of [Method 2] described above in the first embodiment is that even though the terminal and the base station can predict and know the change of the TCI state over time, the terminal and the base station unconditionally set one TCI state for a specific time. It may be that you have to use it. In addition, in the case of [Method 1] described above, if the base station and the terminal want to change up to 8 currently activated TCI state codepoints, the base station can perform the PDSCH TCI state activation MAC-CE based on the terminal, but this is the PDCCH Due to a process from transmission to PUCCH transmission including HARQ-ACK for PDSCH and a time delay occurring from an additional 3 ms, it may be inflexible when changing to a desired TCI state codepoint. If the terminal and the base station can predict the change of the TCI state over time and know in advance when the candidate groups of the TCI state codepoint change, the terminal does not change to a new codepoint based on the MAC-CE and the base station and the terminal It may be advantageous to automatically change the TCI state codepoint according to the defined time. Therefore, in this embodiment, a method for predicting a change in TCI state over time by a terminal and a base station and setting TCI state candidates having a very high possibility of use during a specific time, that is, a method of setting codepoints of a TCI state field in advance will be described. . In the following description, the aforementioned TCI candidate presetting and indication-based transmission/reception beam control method may be named [Method 3].

For [Method 3], the terminal can receive a list of a plurality of TCI state codepoint sets from the base station and a time to apply each TCI state codepoint set. Corresponding higher layer signaling may have the following configuration information structure.

Pre-configured-TCI-state-codepoint-list ::= SEQUENCE {

pre-configured-TCI-state-candidate-set-list SEQUENCE (SIZE (1, ..., maxNrofPreConfiguredTCIStateCandidateSet)) OF pre-configured-TCI-state-candidate-set,

appliedTime-list SEQUENCE(SIZE(1, ..., maxNrofPreConfiguredTCIStateCandidateSet)) OF appliedTime

}

pre-configured-TCI-state-candidate-set ::= SEQUENCE(SIZE(1, ..., 8)) OF TCI-StateId

In the upper layer signaling structure, pre-configured-TCI-state-candidate-set-list is higher-layer signaling meaning the order of the above-described plurality of TCI state codepoint sets, and appliedTime-list is pre-configured-TCI -Upper layer signaling that means the application retention time of each TCI state codepoint set set in state-candidate-set-list, and maxNrofPreConfiguredTCIStateCandidateSet means the maximum number of multiple TCI state codepoint sets that can be set in this way It may be higher layer signaling that That is, during the first appliedTime in the appliedTime-list, each TCI state set in the first pre-configured-TCI-state-candidate-set in the pre-configured-TCI-state-candidate-set-list is a TCI state field in DCI. It is applied to each codepoint of , receives a downlink signal by instructing one of the TCI states of the first pre-configured-TCI-state-candidate-set with DCI, and after the first appliedTime has elapsed, the above During the second appliedTime in appliedTime-list, each TCI state set in the second pre-configured-TCI-state-candidate-set in the pre-configured-TCI-state-candidate-set-list is each code of the TCI state field in DCI. When applied to a point, a downlink signal may be received by indicating one TCI state of the second pre-configured-TCI-state-candidate-set as DCI. Up to 8 TCI-StateIds can be set in each pre-configured-TCI-state-candidate-set, and each TCI-StateId can correspond to each code point of the TCI state field in DCI.

According to one disclosure, if the UE is configured for the higher layer signaling, instead of using the [Method 1], the UE corresponds to a pre-configured-TCI-state for a specific time defined by appliedTime according to the configuration. A downlink signal can be received based on TCI states defined by -candidate-set. At this time, after receiving the downlink signal using the last pre-configured-TCI-state-candidate-set in the pre-configured-TCI-state-candidate-set-list during the last appliedTime in the appliedTime-list, , the same method can be repeated again using the first appliedTime and the first pre-configured-TCI-state-candidate-set.

According to an embodiment, if the UE is configured for the higher layer signaling, the UE can select between the [Method 1] and the [Method 3] based on a specific MAC-CE. If the UE receives the MAC-CE that activates [Method 3], the UE receives the last symbol of the PUCCH transmission including HARQ-ACK information indicating whether the PDSCH including the corresponding MAC-CE is successfully received. [Method 3] can be used from the time point after 3 ms. At this time, after receiving the downlink signal using the last pre-configured-TCI-state-candidate-set in the pre-configured-TCI-state-candidate-set-list during the last appliedTime in the appliedTime-list, Transmission/reception beam control can be performed based on [Method 1] without using [Method 3]. Alternatively, until the terminal receives a MAC-CE indicating deactivation for the [Method 3], if the pre-configured-TCI-state-candidate-set- After receiving the downlink signal using the last pre-configured-TCI-state-candidate-set in the list, the same method can be repeated using the first appliedTime and pre-configured-TCI-state-candidate-set. there is. The activation method for the aforementioned MAC-CE-based [Method 3] may also be possible through DCI, and when specific fields in DCI have specific values using DCI format 1_1 or 1_2, it may mean activation or inactivation. there is.

- DCI format 1_1 or 1_2 with CRC scrambled as CS-RNTI or new RNTI

- All bits allocated to RV (Redundancy Version) field and MCS (Modulation and Coding Scheme) field have 0

- Regarding the Frequency Domain Resource Allocation (FDRA) field

n When the frequency resource allocation method is set to Type 0 or dynamicSwitch, all bits allocated to the FDRA field have 1

n When the frequency resource allocation method is set to Type 1, all bits allocated to the FDRA field have 0

- All bits assigned to the HARQ Process Number field have 1

- If all bits assigned to the NDI (New Data Indicator) field have 0, they are active, and if they are 1, they are inactive.

Higher layer signaling for [Method 3] may exist in various forms as follows.

According to an embodiment, there is one higher layer signaling for [Method 3], and the higher layer signaling for [Method 3] can be applied only to transmission/reception beam control for the PDSCH. At this time, the remaining downlink channels/signals such as PDCCH or CSI-RS may be operated according to existing methods. That is, a MAC-CE based TCI state activation method may be used for the PDCCH, and a TCI state configured by higher layer signaling may be used for the CSI-RS. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 3], and the higher layer signaling for [Method 3] can be applied only to transmission/reception beam control for PDCCH and PDSCH. That is, the same Rx beams can be used for downlink control and data channels, and in the case of PDCCH, they can be applied to all control resource sets connected to a common search space and a UE-specific search space. When applied to the PDCCH, the UE identifies the PDCCH reception beam using the first TCI state corresponding to the first code point of the TCI state field in the DCI among the TCI-States set in the pre-configured-TCI-state-candidate-set. can do. At this time, the TCI state set by higher layer signaling may be used in the CSI-RS as in the conventional method. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 3], and the higher layer signaling for [Method 3] can be applied only to transmission/reception beam control for PDCCH and PDSCH. That is, the same Rx beams for downlink control and data channels may be used. In particular, in the case of PDCCH, unlike the above, it can be applied only to a control resource set connected only to a UE-specific search space. If a certain control resource set is connected to both the common search space and the terminal-specific search space, transmission/reception beam control may be performed based on [Method 1]. When applied to the PDCCH, the UE identifies the PDCCH reception beam using the first TCI state corresponding to the first code point of the TCI state field in the DCI among the TCI-States set in the pre-configured-TCI-state-candidate-set. can do. At this time, the TCI state set by higher layer signaling may be used in the CSI-RS as in the conventional method. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 3], and higher layer signaling for [Method 3] can be applied to PDCCH, PDSCH, and CSI-RS excluding SSB and TRS. When applied to PDCCH and CSI-RS, the UE uses the first TCI state corresponding to the first code point of the TCI state field in DCI among the TCI-States set in the pre-configured-TCI-state-candidate-set to use the PDCCH A receive beam can be identified. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals.

According to an embodiment, there is one higher layer signaling for [Method 3], and higher layer signaling for [Method 3] can be applied to PDCCH, PDSCH, and CSI-RS excluding SSB and TRS. When applied to PDCCH and CSI-RS, the UE uses the first TCI state corresponding to the first code point of the TCI state field in DCI among the TCI-States set in the pre-configured-TCI-state-candidate-set to use the PDCCH A receive beam can be identified. In the case of CSI-RS, [Method 3] can be applied only when higher layer signaling, which means whether to apply [Method 3] to a specific CSI-RS resource, is set, or only for aperiodic CSI-RS resources [ [Method 3] can be applied without higher layer signaling having meaning on whether or not Method 3 is applied. In addition, the same higher layer signaling configuration and MAC-CE based activation method can be used for spatial relation info applied to uplink signals. As another method for the uplink transmission/reception beam, the terminal may apply one set higher layer signaling to the uplink transmission/reception beam as well. In this case, applying the TCI-State to the Tx beam of the UE may mean that the UE determines the uplink Tx beam based on the QCL-TypeD reference RS set in the TCI-State.

According to an embodiment, there is one higher layer signaling for [Method 3], and higher layer signaling for [Method 3] can be applied to PDCCH, PDSCH, and CSI-RS excluding SSB and TRS, and can be applied to PUSCH, Based on a higher layer signaling configuration that is standardized on whether to apply to some or all of PUCCH, SRS, and PRACH, or has a meaning of whether to apply [Method 3] within resource configuration for each uplink channel/signal it might work When applied to PDCCH, CSI-RS, PUSCH, PUCCH, SRS, and PRACH, the UE corresponds to the first codepoint of the TCI state field in DCI among TCI-States set in pre-configured-TCI-state-candidate-set A PDCCH reception beam can be identified using the first TCI state. In this case, applying the TCI-State to the Tx beam of the UE may mean that the UE determines the uplink Tx beam based on the QCL-TypeD reference RS set in the TCI-State. For example, [Method 3] is applicable to PUSCH transmission and UE-specific PUCCH resources, and an existing method can be used for SRS and PRACH.

According to an embodiment, when defining the UE capability report for [Method 3], the UE may consider at least one of the following.

- [Method 3] Range of downlink channels/signals applied when supported

- [Method 3] Range of uplink channels/signals applied when supported

- How to select between [Method 1] and [Method 3]: A supported method among RRC, MAC-CE, and DCI-based methods

- [Method 3] The maximum number of transmit/receive beams that can be set if supported (maxNrofPreConfiguredTCIStateCandidateSet above)

26 is a diagram illustrating a TCI candidate presetting and instruction-based transmit/receive beam control scheme according to an embodiment of the present disclosure.

In this figure, it can be assumed that the terminal operates based on MAC-CE for the selection method among [Method 1] and [Method 3]. In addition, in the figure, it is assumed that the terminal receives one higher layer signaling for the [Method 3] and applies the higher layer signaling to all downlink and uplink channels/signals except SSB and TRS. can In addition, in this figure, it can be assumed that the terminal receives settings for higher layer signaling from the base station as in (26-27).

The terminal may receive a DCI for scheduling a PDSCH including a MAC-CE indicating activation of [Method 3] from the base station (26-00), and upon receiving the DCI, the corresponding DCI is received based on [Method 1] It can be assumed that TCI-State#1 is activated for the control resource set to be used (26-03). For example, it can be assumed that TCI-state#1 is activated by PDCCH TCI state activation MAC-CE received 3 ms before DCI (26-00) reception. The terminal may receive a PDSCH including a MAC-CE indicating activation of [Method 3] based on the corresponding DCI from the base station (26-01), and upon receiving the PDSCH, based on [Method 1], the TCI-State It can be assumed that #2 is instructed (26-04). For example, it can be assumed that TCI-state#2 is indicated by DCI (26-00). Thereafter, the terminal may transmit to the base station a PUCCH including HARQ-ACK information indicating whether reception of the PDSCH including the MAC-CE indicating activation of [Method 3] is successful (26-02), and when transmitting the PUCCH Based on [Method 1], it can be assumed that pucch-spatialRelationInfo#1 connected to the corresponding PUCCH resource is used (26-05). If the UE succeeds in receiving the PDSCH including the MAC-CE and transmits the ACK information through the PUCCH, the UE's transmission/reception beam until (26-07) 3 ms after the PUCCH transmission and before (26-06) The control method can be operated based on [Method 1], and from the time point (26-06) after 3 ms after PUCCH transmission (26-08), the UE transmit/receive beam control method is based on [Method 3] can be operated. As described above, for the PDSCH, the UE is pre-configured-TCI-state- Each TCI-State set in candidate-set1 corresponds to each code point of the TCI state field in DCI, and the reception beam of the UE can be identified through the TCI state field in DCI, and all downlink and For uplink channels/signals, TCI-State#1, which is the first TCI state set in pre-configured-TCI-state-candidate-set1, can be used as a transmission/reception beam. That is, DCI (26-09) received by the UE during appliedTime#1 can be received based on TCI-State#1 (26-11), and the reception beam for the PDSCH (26-10) scheduled by the corresponding DCI is It can be determined as TCI-State#5 indicated through the TCI state field in DCI (26-12). As described above, from the point at which appliedTime#1 ends (26-14) to appliedTime#2 (26-16), the UE sets each value set in pre-configured-TCI-state-candidate-set2 for the PDSCH as described above. The TCI-State corresponds to each code point of the TCI state field in DCI, and the reception beam of the UE can be identified through the TCI state field in DCI, and all downlink and uplink channels / signals except PDSCH, SSB, and TRS For TCI-State#2, which is the first TCI state set in pre-configured-TCI-state-candidate-set2, can be used as a transmit/receive beam. That is, the DCI (26-17) received by the UE during appliedTime#2 can be received based on TCI-State#2 (26-19), and the reception beam for the PDSCH (26-18) scheduled by the DCI is It can be determined as TCI-State#3 indicated through the TCI state field in DCI (26-20). Similarly, the terminal may perform transmit/receive beam control using the set TCI-State for a set time similar to the above from the point (26-22) when appliedTime#2 ends (26-24).

27 is a diagram illustrating operations of a base station for a TCI candidate presetting and indication-based transmit/receive beam control scheme according to an embodiment of the present disclosure. The base station may receive a terminal capability report from the terminal (2700). At this time, the information that the base station can receive may include at least one of the terminal capability reports. Thereafter, the base station may transmit configuration information related to transmission/reception beams to the terminal by referring to the terminal capability report (2701). Thereafter, the base station can perform transmission/reception beam control operation of the terminal using [Method 3] when a specific condition is satisfied (2702), and when the specific condition is not satisfied (2702) [Method 1] is used. can Possible conditions at this time are when higher layer signaling is set for [Method 3] as described above, when MAC-CE indicating activation for using [Method 3] is received, or when DCI is received can be

28 is a diagram illustrating operations of a terminal in relation to TCI candidate presetting and indication-based transmit/receive beam control method according to an embodiment of the present disclosure. The terminal may transmit a terminal capability report to the base station (2800). At this time, the information that the base station can receive may include at least one of the terminal capability reports. Thereafter, the terminal may transmit configuration information related to transmission/reception beams from the base station (2801). Thereafter, when a specific condition is satisfied (2802), the terminal can perform transmission/reception beam control operations when receiving downlink from the base station and transmitting uplink to the base station using [Method 3] (2804), and the specific condition is satisfied. If not, (2802) [Method 1] can be used. Possible conditions at this time are when higher layer signaling is set for [Method 3] as described above, when MAC-CE indicating activation for using [Method 3] is received, or when DCI is received can be

<Third Embodiment: Channel State Information Feedback Method Based on Channel State Information Prediction>

As an example of an embodiment of the present disclosure, a channel state information (CSI) feedback method based on channel state information prediction in a terminal will be described. The terminal may receive the CSI-RS from the base station, generate CSI considering a plurality of viewpoints on the time axis through a channel state information prediction function, and report it to the base station. At this time, the single or multiple CSI-RS resources that the UE can receive for use in CSI generation are CSI-RS for tracking (when trs-info, which is higher layer signaling), CSI-RS for CSI (higher layer signaling) A combination of at least one of layer signaling trs-info and repetition is not set), CSI-RS for beam management (upper layer signaling, repetition is set), or CSI-RS for mobility. At this time, among the reported CSI, at least one of CRI, CQI, PMI, RI, and LI may be channel state information that may vary for each view among a plurality of views on the time axis. If the terminal generates CSI considering N (N is a natural number of 2 or more) views on the time axis through the channel state information prediction function and reports it to the base station, the terminal includes different CQIs for each viewpoint and reports it. Depending on the higher layer signaling configuration received from the base station, at least one of the following methods may be combined to generate CQIs corresponding to N views and include them in the CSI report.

- For example, the terminal may generate independent CQIs for each N views. The CQI for each time point may be reported according to a CQI reporting unit on a frequency resource according to higher layer signaling configuration at that point in time, or only wideband CQI and subband CQI may be reported together. For example, the UE may quantize and report the wideband CQI to a specific number of bits (e.g., 4 bits), and if the UE reports the subband CQI, the differential CQI calculated from the wideband CQI value is a specific number of bits ( e.g., 2 bits) can be quantized and reported.

■ The meaning of generating an independent CQI for each view may mean that quantization is not performed by using the value of each view as a reference when performing quantization for each view. That is, it may mean that the CQI value of the first time point does not affect (irrelevant to) the quantization of the CQI value of the second time point.

■ CQI reporting units on frequency resources are different for each time point, so they can all have the same value based on independent higher layer signaling or through single higher layer signaling. For example, the base station may transmit higher layer signaling to report only the wideband CQI for all viewpoints considered for CSI reporting to the terminal. As another example, the base station may transmit higher layer signaling configuration to allow the terminal to report the wideband CQI at a specific time point among the time points considered for CSI reporting, and the wideband CQI and subband CQI at another time point. As another example, the base station may transmit higher layer signaling so that the UE reports reports on the wideband CQI and subband CQI up to a specific point in time, and reports only the wideband CQI for all points in time after the specific point in time.

- For example, the terminal may generate dependent CQIs for each N views. For the first time point, the UE may report only the wideband CQI or report both the wideband CQI and the subband CQI according to the CQI reporting unit on the frequency resource according to the upper layer signaling configuration at that time point. For all time points after the first time point, the UE may calculate a differential CQI based on the CQI value calculated at the first time point and include it in the CSI report. At this time, for wideband CQI reports for all time points after the first time point, differential CQI is calculated based on the wideband CQI value calculated at the first time point. It can be the number of bits. In addition, for subband CQIs for all time points after the first time point, differential CQI is calculated based on the wideband CQI value calculated at the first time point, or differential CQI value is based on the subband CQI value of the same frequency resource location at the first time point. The CQI is calculated, or the differential CQI is calculated based on the wideband CQI value at that time. The number of bits used in this case may be 2 bits or the number of bits of another value, for example.

■ When calculating the wideband CQI or subband CQI for all views after the first view, as described above, the base station informs the UE about what value to calculate the differential CQI value for, as described above, in an independent upper layer for each view after the first view. Wideband or subband CQI calculation may be considered using methods independent of each other by transmitting signaling configuration. Alternatively, the base station tells the UE to have the same CQI calculation method for all points in time after the first point in time considered for CSI reporting (for example, the wideband and subbnad CQIs calculated for all points in time after the first point in time are The differential CQI value is calculated based on the wideband CQI of The subband CQI calculated for all views may calculate a differential CQI value based on the wideband CQI at each view) Higher layer signaling may be transmitted.

■ CQI reporting units on frequency resources are different for each time point, so they can all have the same value based on independent higher layer signaling or through single higher layer signaling. For example, the base station allows the UE to have a CQI reporting unit on the same frequency resource for all views considered for CSI reporting (for example, to report only wideband CQI for all views, or wideband CQI and subband CQI for all views). may be reported) Higher layer signaling may be transmitted. As another example, the base station may transmit higher layer signaling configuration so that the UE reports the wideband CQI at a specific time point and the wideband CQ and subband CQI at another time point for each time point considered for CSI reporting. As another example, the base station may transmit higher layer signaling so that the UE reports reports on the wideband CQI and subband CQI up to a specific point in time, and reports only the wideband CQI for all points in time after the specific point in time.

In addition, the terminal may include information on the N viewpoints considered when generating the CSI when reporting the CSI and report the information to the base station.

The terminal may report the terminal capability for the channel state information feedback method based on the channel state information prediction to the base station. In this case, the channel state information feedback method based on the above-described channel state information prediction may include at least one or more of methods to be described later.

- A CSI reporting method that includes a plurality of time points on the time axis and calculates based on each time point

- Method for generating independent CQI for each of a plurality of time points

■ How to independently set the CQI reporting unit on frequency resources for each time point

■ How to set the CQI reporting unit to a single value on frequency resources for each time point

■ A method of using both wideband and subband as CQI reporting units on frequency resources until a specific point in time, and then using only wideband for all points in time

- Method for generating dependent CQIs for each of a plurality of time points

■ How to calculate differential CQI based on X-bit based on the wideband CQI of the first time point when calculating wideband and subband CQI for all time points after the first time point (X can be 2 bits as an example)

■ When calculating wideband CQI for all time points after the first time point, differential CQI is calculated based on X-bit based on the wideband CQI at the first time point (X can be 2 bits, for example), and the first time point How to calculate differential CQI based on X-bit based on wideband CQI at each time point after the first time point when subband CQI is calculated for all subsequent time points (X can be 2 bits as an example).

■ When calculating wideband CQI for all time points after the first time point, differential CQI is calculated based on X-bit based on the wideband CQI at the first time point (X can be 2 bits, for example), and the first time point How to calculate the differential CQI at each time point based on the X-bit based on the subband CQI for each subband at the same location at the first time point when calculating the subband CQI for each subband for all subsequent time points (X is an example) 2 bits may be possible).

29 is a diagram illustrating a structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 29 , a terminal may include a terminal receiving unit 2900 and a transceiver that refers to a terminal transmitting unit 2910, a memory (not shown), and a terminal processing unit 2905 (or a terminal control unit or processor). According to the communication method of the terminal described above, the transmission/reception units 2900 and 2910, the memory and the terminal processing unit 2905 of the terminal may operate. However, the components of the terminal are not limited to the above-described examples. For example, a terminal may include more or fewer components than the aforementioned components. In addition, the transceiver, memory, and processor may be implemented in a single chip form.

The transmitting/receiving unit may transmit/receive signals with the base station. Here, the signal may include control information and data. To this end, the transceiver unit may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting the frequency. However, this is only one embodiment of the transceiver, and components of the transceiver are not limited to the RF transmitter and the RF receiver.

Also, the transceiver may receive a signal through a wireless channel, output the signal to the processor, and transmit the signal output from the processor through the wireless channel.

The memory may store programs and data required for operation of the terminal. In addition, the memory may store control information or data included in signals transmitted and received by the terminal. The memory may include a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, there may be a plurality of memories.

In addition, the processor may control a series of processes so that the terminal can operate according to the above-described embodiment. For example, the processor may control components of the terminal to simultaneously receive a plurality of PDSCHs by receiving DCI composed of two layers. There may be a plurality of processors, and the processors may perform component control operations of the terminal by executing a program stored in a memory.

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

Referring to FIG. 30 , a base station may include a base station receiving unit 3000 and a transmitting/receiving unit that refers to a base station transmitting unit 3010, a memory (not shown), and a base station processing unit 3005 (or a base station control unit or processor). According to the communication method of the base station described above, the transmission/reception units 3000 and 3010 of the base station, the memory and the base station processing unit 3005 can operate. However, components of the base station are not limited to the above-described examples. For example, a base station may include more or fewer components than those described above. In addition, the transceiver, memory, and processor may be implemented in a single chip form.

The transmission/reception unit may transmit/receive signals with the terminal. Here, the signal may include control information and data. To this end, the transceiver unit may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, and an RF receiver for low-noise amplifying a received signal and down-converting the frequency. However, this is only one embodiment of the transceiver, and components of the transceiver are not limited to the RF transmitter and the RF receiver.

Also, the transceiver may receive a signal through a wireless channel, output the signal to the processor, and transmit the signal output from the processor through the wireless channel.

The memory may store programs and data necessary for the operation of the base station. In addition, the memory may store control information or data included in signals transmitted and received by the base station. The memory may include a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of storage media. Also, there may be a plurality of memories.

The processor may control a series of processes so that the base station operates according to the above-described embodiment of the present disclosure. For example, the processor may configure and transmit two layers of DCIs including allocation information for a plurality of PDSCHs and may control each element of the base station. There may be a plurality of processors, and the processors may perform a component control operation of the base station by executing a program stored in a memory.

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

Such programs (software modules, software) may include random access memory, non-volatile memory including flash memory, read only memory (ROM), and 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 other forms of It can be stored on optical storage devices, magnetic cassettes. Alternatively, it may be stored in a memory composed of a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

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

In the specific embodiments of the present disclosure described above, components included in the invention are expressed in singular or plural numbers according to the specific embodiments presented. However, the singular or plural expressions are selected appropriately for the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components, and even components expressed in plural are composed of the singular number or singular. Even the expressed components may be composed of a plurality.

On the other hand, the embodiments of the present disclosure disclosed in the present specification and drawings are only presented as specific examples to easily explain the technical content of the present disclosure and help understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. That is, it is obvious to those skilled in the art that other modifications based on the technical idea of the present disclosure are possible. In addition, each of the above embodiments can be operated in combination with each other as needed. For example, a base station and a terminal may be operated by combining parts of one embodiment of the present disclosure and another embodiment. For example, a base station and a terminal may be operated by combining parts of the first embodiment and the second embodiment of the present disclosure. In addition, although the above embodiments have been presented based on the FDD LTE system, other modifications based on the technical idea of the above embodiment may be implemented in other systems such as a TDD LTE system, 5G or NR system.

Meanwhile, the order of explanation in the drawings for explaining the method of the present invention does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

Alternatively, drawings describing the method of the present invention may omit some of the elements and include only some of the elements within the scope of not impairing the essence of the present invention.

In addition, the method of the present invention may be executed by combining some or all of the contents included in each embodiment within a range that does not impair the essence of the invention.

Various embodiments of the present disclosure have been described above. The foregoing description of the present disclosure is for illustrative purposes, and the embodiments of the present disclosure are not limited to the disclosed embodiments. Those of ordinary skill in the art to which the present disclosure belongs will be able to understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present disclosure. The scope of the present disclosure is indicated by the following claims rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts should be interpreted as being included in the scope of the present disclosure. do.

Claims (1)

A control signal processing method in a wireless communication system,
Receiving a first control signal transmitted from a base station;
processing the received first control signal; and
and transmitting a second control signal generated based on the processing to the base station.

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