KR20210020740A - Appratus and method for transmission of uplink control information in network cooperative communication - Google Patents

Abstract

The present disclosure relates to a communication technique fusing IoT technology with a 5G communication system for supporting a data transmission rate higher than a 4G system, and a system thereof. The present disclosure can be applied to intelligent services based on 5G communication technology and IoT-related technology (for example, a smart home, a smart building, a smart city, a smart car or connected car, healthcare, digital education, retail business, security and safety-related services and the like). The method includes the following steps of: receiving a first control signal; processing the first control signal; and transmitting a second control signal to a base station.

Description

Method and apparatus for transmitting uplink control information for network cooperative communication {APPRATUS AND METHOD FOR TRANSMISSION OF UPLINK CONTROL INFORMATION IN NETWORK COOPERATIVE COMMUNICATION}

The present disclosure (disclosure) relates to a wireless communication system, and more specifically, to a method and apparatus for a terminal to transmit uplink control information to multiple transmission points/panels/beams for cooperative communication between multiple transmission points/panels/beams. For.

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

On the other hand, the Internet is evolving from a human-centered network in which humans generate and consume information, to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with cloud servers, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between objects, machine to machine , M2M), and MTC (Machine Type Communication) technologies are being studied. In the IoT environment, intelligent IT (Internet Technology) services that create new value in human life by collecting and analyzing data generated from connected objects can be provided. IoT is the field of smart home, smart building, smart city, smart car or connected car, smart grid, healthcare, smart home appliance, advanced medical service, etc. through the convergence and combination of existing IT (information technology) technology and various industries. Can be applied to.

Accordingly, various attempts have been made to apply a 5G communication system to an IoT network. For example, technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication) are implemented by techniques such as beamforming, MIMO, and array antenna. There is. As the big data processing technology described above, a cloud radio access network (cloud RAN) is applied as an example of the convergence of 5G technology and IoT technology.

The present disclosure (disclosure) provides a method for a terminal to transmit uplink control information to a plurality of transmission points (transmission point) / panel / beam for network coordination in a wireless communication system.

The present invention for solving the above problem is a control signal processing method in a wireless communication system, the method comprising: 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.

According to the present disclosure, when network cooperative communication is used in a wireless communication system, a time required for a terminal to transmit uplink control information to each transmission point/panel/beam can be shortened.

1 is a diagram showing a basic structure of a time-frequency domain of a mobile communication system according to an embodiment of the present disclosure.
2 is a diagram illustrating a frame, subframe, and slot structure of a mobile communication system according to an embodiment of the present disclosure.
3 illustrates an example of a configuration of a bandwidth part (BWP) 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.
5 is a diagram illustrating a structure of a downlink control channel of a mobile communication system according to an embodiment of the present disclosure.
6 is a diagram illustrating an example of allocation of a frequency axis resource of a physical downlink shared channel (PDSCH) in a wireless communication system according to an embodiment of the present disclosure.
7 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.
8 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.
9 is a diagram illustrating a case of overlapping a plurality of PUCCH resources for HARQ-ACK transmission for PDSCH when multi-slot repetition is not configured according to an embodiment of the present disclosure.
FIG. 10 is a diagram illustrating a case in which a PUCCH resource overlaps when multi-slot repetition is set according to an embodiment of the present disclosure.
11 is a diagram illustrating a structure of a base station and a terminal radio protocol when performing single cell, carrier aggregation, and dual connectivity according to an embodiment of the present disclosure.
12 is a diagram illustrating an example of an antenna port configuration and resource allocation for cooperative communication according to some embodiments in a wireless communication system according to an embodiment of the present disclosure.
13 is a diagram illustrating an example configuration of downlink control information (DCI) for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.
14A, 14B, 14C, and 14D are diagrams illustrating HARQ-ACK reporting for non-coherent joint transmission (NC-JT) transmission according to an embodiment of the present disclosure.
15a is a diagram illustrating a case in which overlap occurs between PUCCH resources according to an embodiment of the present disclosure.
15B is a diagram illustrating a method of transmitting a PUCCH when an overlap occurs between PUCCH resources according to an embodiment of the present disclosure.
16A, 16B, and 16C show type 1 HARQ-ACK codebook methods for each of repeated PDSCH transmission over multiple slots, repeated PDSCH transmission within a single slot, and no repeated transmission according to an embodiment of the present disclosure It is a drawing.
17 illustrates a structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.
18 illustrates a structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

Hereinafter, embodiments of the present invention 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 invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention by omitting unnecessary description.

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

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, and only the embodiments of the present disclosure make the present disclosure complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the present disclosure is only defined by the scope of the claims. The same reference numerals refer to the same components throughout the specification.

In this case, it will be appreciated that each block of the flowchart diagrams and combinations of the flowchart diagrams may be executed by computer program instructions. Since these computer program instructions can be mounted on the processor of a general purpose computer, special purpose computer or other programmable data processing equipment, the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates a means to perform functions. These computer program instructions can also be stored in computer-usable or computer-readable memory that can be directed to a computer or other programmable data processing equipment to implement a function in a particular way, so that the computer-usable or computer-readable memory It may also be possible to produce an article of manufacture containing instruction means for performing the functions described in the flowchart block(s). Computer program instructions can also be mounted on a computer or other programmable data processing equipment, so that a series of operating steps are performed on a computer or other programmable data processing equipment to create a computer-executable process to create a computer or other programmable data processing equipment. Instructions to perform processing equipment may also be capable of providing steps for executing the functions described in the flowchart block(s).

In addition, each block may represent a module, segment, or part of code that contains one or more executable instructions for executing the specified logical function(s). In addition, it should be noted that in some alternative execution examples, functions mentioned in blocks may occur out of order. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order depending on the corresponding function.

At this time, the term'~ unit' used in this embodiment refers to software or hardware components such as field programmable gate array (FPGA) or application specific integrated circuit (ASIC), and'~ unit' performs certain roles. do. However,'~ part' is not limited to software or hardware. The'~ unit' may be configured to be in an addressable storage medium, or may be configured to reproduce one or more processors. Therefore, according to some embodiments,'~ unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and programs. Includes procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The components and functions provided in the'~ units' may be combined into a smaller number of elements and'~ units' or further separated into additional elements and'~ units'. In addition, components and'~ units' may be implemented to play one or more CPUs in a device or a security multimedia card. In addition, according to some embodiments, the'~ unit' may include one or more processors.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary depending on the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout this specification. Hereinafter, the base station is a subject that performs resource allocation of the terminal, and may be at least one of a gNode B, 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 a communication function. Of course, it is not limited to the above example. Hereinafter, the present disclosure describes a technique for a terminal to receive broadcast information from a base station in a wireless communication system. The present disclosure relates to 5G (5 ^th generation) communication system to support higher data rates than after 4G (4 ^th generation) system, a communication method and a system for fusing and IoT (Internet of Things, things, Internet) technology. This disclosure is based on 5G communication technology and IoT-related technology, and intelligent services (for example, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail, security and safety related services, etc. ) Can be applied.

In the following description, a term referring to broadcast information, a term referring to control information, a term related to communication coverage, a term referring to a state change (e.g., event), and network entities A term referring to, a term referring to messages, a term referring to a component of a device, and the like are exemplified for convenience of description. Accordingly, the present invention is not limited to terms to be described later, and other terms having equivalent technical meanings may be used.

For convenience of description below, some terms and names defined in the 3GPP 3rd generation partnership project long term evolution (LTE) standard may be used. However, the present invention is not limited by the terms and names, and can be applied equally to systems conforming to other standards.

The wireless communication system deviated from the initial voice-oriented service, for example, 3GPP 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. It is developing into a communication system.

As a representative example of a broadband wireless communication system, the LTE system employs an Orthogonal Frequency Division Multiplexing (OFDM) scheme in downlink (DL), and Single Carrier Frequency Division Multiplexing (SC-FDMA) scheme in uplink (UL). ) Method is adopted. Uplink refers to a radio link through 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 base station It refers to a wireless link that transmits data or control signals. The multiple access method as described above divides the data or control information of each user by assigning and operating time-frequency resources to carry data or control information for each user so that they do not overlap with each other, that is, orthogonality is established. .

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

According to some embodiments, eMBB aims to provide a data transmission speed that is more improved than the data transmission speed supported by the existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to provide a maximum transmission rate of 20 Gbps in downlink and 10 Gbps in uplink from the viewpoint of one base station. At the same time, it is necessary to provide an increased user perceived data rate. In order to satisfy these requirements, it is required to improve the transmission and reception technology, including a more advanced multi-input multi-output (MIMO) transmission technology. In addition, by using a frequency bandwidth wider than 20 MHz in a frequency band of 3 to 6 GHz or 6 GHz or higher instead of the 2 GHz band used by the current LTE, the data transmission speed required by the 5G communication system can be satisfied.

At the same time, mMTC is being considered to support application services such as the Internet of Thing (IoT) in 5G communication systems. In order to efficiently provide the Internet of Things, mMTC may require large-scale terminal access support within a cell, improved terminal coverage, improved battery time, and reduced terminal cost. The IoT is attached to various sensors and various devices to provide a communication function, so it must be able to support a large number of terminals (for example, 1,000,000 terminals/km2) within a cell. In addition, because the terminal supporting mMTC is highly likely to be located in a shaded area not covered by the cell, such as the basement of a building due to the characteristics of the service, it may require wider coverage than other services provided by the 5G communication system. A terminal supporting mMTC must be configured as a low-cost terminal, and since it is difficult to frequently exchange the battery of the terminal, a very long battery life time may be required.

Finally, in the case of URLLC, as a cellular-based wireless communication service used for a specific purpose (mission-critical), remote control for robots or machinery, industrial automation, and As a service used for unmaned aerial vehicles, remote health care, emergency alerts, etc., communication with ultra low latency and ultra reliability must be provided. For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds, and at the same time have a requirement of a packet error rate of 10-5 or less. Therefore, for a service supporting URLLC, a 5G system must provide a smaller Transmit Time Interval (TTI) than other services, and at the same time, a design requirement to allocate a wide resource in a frequency band is required. However, the aforementioned mMTC, URLLC, and eMBB are only examples of different service types, and the service types to which the present disclosure is applied are not limited to the above-described example.

The services considered in the 5G communication system described above should be provided by fusion with each other based on one framework. That is, for efficient resource management and control, it is preferable that each service is integrated into one system, controlled and transmitted rather than independently operated.

In addition, an embodiment of the present invention will be described below using an LTE, LTE-A, LTE Pro, or NR system as an example, but the embodiment of the present invention may be applied to other communication systems having a similar technical background or channel type. In addition, the embodiments of the present invention may be applied to other communication systems through some modifications without significantly departing from the scope of the present invention, as determined by a person having skilled technical knowledge.

The present disclosure relates to a method and apparatus for reporting channel state information to increase power saving efficiency of a terminal in a wireless communication system.

According to the present disclosure, when a terminal operates in a power saving mode in a wireless communication system, a power saving effect may be further improved by optimizing a method of reporting channel state information accordingly.

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

1 is a diagram showing a basic structure of a time-frequency domain of a mobile communication system according to an embodiment of the present disclosure.

Referring to FIG. 1, in FIG. 1, the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The basic unit of a resource in the time and frequency domain is a resource element (RE, 1-01), 1 OFDM (Orthogonal Frequency Division Multiplexing) symbol (1-02) on the time axis and 1 subcarrier (Subcarrier) on the frequency axis ( 1-03) can be defined. In the frequency domain, N_sc^RB (for example, 12) consecutive REs may constitute one resource block (Resource Block, RB, 1-04). In one embodiment, a plurality of OFDM symbols may constitute one subframe (1-10).

FIG. 2 is a diagram illustrating a frame, subframe, and slot structure of a next-generation mobile communication system according to an embodiment of the present disclosure.

)=14). 1 서브프레임(2-01)은 하나 또는 다수 개의 슬롯(2-02, 2-03)으로 구성될 수 있으며, 1 서브프레임(2-01)당 슬롯(2-02, 2-03)의 개수는 부반송파 간격에 대한 설정 값 μ(2-04, 2-05)에 따라 다를 수 있다. 도 2의 일 예에서는 부반송파 간격 설정 값으로 μ=0(2-04)인 경우와 μ=1(2-05)인 경우가 도시되어 있다. μ=0(2-04)일 경우, 1 서브프레임(2-01)은 1개의 슬롯(2-02)으로 구성될 수 있고, μ=1(2-05)일 경우, 1 서브프레임(2-01)은 2개의 슬롯(2-03)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 1]과 같이 정의될 수 있다.2, one frame (Frame, 2-00) is composed of one or more subframes (Subframe, 2-01), and one subframe is composed of one or more slots (Slot, 2-02). I can. For example, one frame (2-00) may be defined as 10 ms. One subframe (2-01) may be defined as 1ms, in this case, one frame (2-00) may be composed of a total of 10 subframes (2-01). One slot (2-02, 2-03) may be defined as 14 OFDM symbols (that is, the number of symbols per slot (

)=14). One subframe (2-01) may be composed of one or a plurality of slots (2-02, 2-03), and the number of slots (2-02, 2-03) per subframe (2-01) May differ depending on the setting value μ(2-04, 2-05) for the subcarrier spacing. In the example of FIG. 2, a case of μ=0 (2-04) and a case of μ=1 (2-05) as subcarrier spacing setting values are illustrated. When μ=0 (2-04), 1 subframe (2-01) may consist of 1 slot (2-02), and when μ=1 (2-05), 1 subframe (2 -01) may be composed of two slots (2-03). That is, the number of slots per 1 subframe according to the setting value μ for the subcarrier spacing (

) May vary, and the number of slots per frame (

) May be different. According to each subcarrier spacing setting μ

And

May be defined as shown in [Table 1] below.

[Table 1]

In NR, one component carrier (CC) or serving cell may consist of a maximum of 250 or more RBs. Therefore, when the terminal always receives the entire serving cell bandwidth like LTE, the power consumption of the terminal can be extreme, and to solve this, the base station sets one or more bandwidth parts (BWP) to the terminal. Thus, it is possible to support the UE to change the reception area within the cell. In NR, the base station may set the'initial BWP', which is the bandwidth of CORESET #0 (or common search space, CSS), to the terminal through the MIB. Thereafter, the base station may set an initial BWP (first BWP) of the terminal through RRC signaling, and may notify at least one or more BWP configuration information that may be indicated through downlink control information (DCI) in the future. Thereafter, the base station can indicate which band the terminal will use by notifying the BWP ID through DCI. If the terminal does not receive DCI in the currently allocated BWP for more than a certain time, the terminal returns to the'default BWP' and attempts DCI reception.

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

Referring to FIG. 3, FIG. 3 shows an example in which a terminal bandwidth 3-00 is set to two bandwidth portions, that is, a bandwidth portion #1 (3-05) and a bandwidth portion #2 (3-10). The base station may set one or a plurality of bandwidth portions to the terminal, and may set information as shown in [Table 2] below for each bandwidth portion.

[Table 2]

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

According to an embodiment, the terminal before the radio resource control (RRC) connection may receive an initial bandwidth part (Initial BWP) for initial access from the base station through a master information block (MIB). More specifically, in order to receive the system information (Remaining System Information; RMSI or System Information Block 1; may correspond to SIB1) required for initial access through the MIB in the initial access step, the terminal controls PDCCH to be transmitted Setting information about a region (Control Resource Set, CORESET) and a search space may be received. The control region and the search space set as the MIB may be regarded as identifiers (Identity, ID) 0, respectively.

The base station may notify the terminal of configuration information, such as frequency allocation information, time allocation information, and numerology, for control region #0 through the MIB. In addition, the base station may notify the UE of the setting information for the monitoring period and occasion for the control region #0, that is, the setting information for the search space #0 through the MIB. The UE may consider the frequency domain set to control region #0 obtained from the MIB as an initial bandwidth part for initial access. In this case, the identifier (ID) of the initial bandwidth part may be regarded as 0.

Setting of a bandwidth part supported by the above-described next-generation mobile communication system (5G or NR system) can be used for various purposes.

For example, when the bandwidth supported by the terminal is smaller than the system bandwidth, the bandwidth supported by the terminal may be supported through the setting of the bandwidth portion. For example, in <Table 2>, the frequency position (setting information 2) of the bandwidth portion is set to the terminal, so that the terminal can transmit and receive data at a specific frequency position within the system bandwidth.

As another example, for the purpose of supporting different neurology, the base station may set a plurality of bandwidth portions to the terminal. For example, in order to support both transmission and reception of data using a subcarrier spacing of 15 kHz and a subcarrier spacing of 30 kHz to an arbitrary terminal, two bandwidth portions may be set to use subcarrier spacings of 15 kHz and 30 kHz, respectively. Different bandwidth portions may be frequency division multiplexed (FDM), and when data is to be transmitted/received at a specific subcarrier interval, a bandwidth portion set at the corresponding subcarrier interval may be activated.

As another example, for the purpose of reducing the power consumption of the terminal, the base station may set a bandwidth portion having a different size of bandwidth to the terminal. For example, if the terminal supports a very large bandwidth, such as 100 MHz, and always transmits/receives data through the corresponding bandwidth, very large power consumption may occur. In particular, it is very inefficient in terms of power consumption for the UE to monitor an unnecessary downlink control channel for a large bandwidth of 100 MHz in a situation where there is no traffic. Therefore, for the purpose of reducing the power consumption of the terminal, the base station may set a bandwidth portion of a relatively small bandwidth to the terminal, for example, a bandwidth portion of 20 MHz. In a situation where there is no traffic, the UE may perform a monitoring operation in the 20 MHz bandwidth portion, and when data is generated, it may transmit and receive data using the 100 MHz bandwidth portion according to the instruction of the base station.

In the above-described method of configuring a bandwidth part, UEs before RRC connection may receive configuration information on an initial bandwidth part through a Master Information Block (MIB) in an initial access step. More specifically, the UE is a control region (Control Resource Set, CORESET) for a downlink control channel through which Downlink Control Information (DCI) scheduling a System Information Block (SIB) can be transmitted from the MIB of the PBCH (Physical Broadcast Channel). ) Can be set. The bandwidth of the control region set as the MIB may be regarded as the initial bandwidth part, and the UE may receive the PDSCH through which the SIB is transmitted through the set initial bandwidth part. In addition to the purpose of receiving the SIB, the initial bandwidth part may be utilized for other system information (OSI), paging, and random access.

Hereinafter, a Synchronization Signal (SS)/PBCH block of a next-generation mobile communication system (5G or NR system) will be described.

The SS/PBCH block may mean a physical layer channel block composed of a Primary SS (PSS), a Secondary SS (SSS), and a PBCH. More specifically, the SS/PBCH block may be defined as follows.

-PSS: A signal that serves as a reference for downlink time/frequency synchronization and may provide some information of the cell ID.

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

-PBCH: It is possible to provide essential system information required for transmission and reception of data channels and control channels of a terminal. The essential system information may include search space-related control information indicating radio resource mapping information of the control channel, scheduling control information for a separate data channel for transmitting system information, and the like.

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

The UE may detect the PSS and SSS in the initial access phase and may decode the PBCH. The UE can obtain the MIB from the PBCH and can receive the control region #0 set through the MIB. The UE may perform monitoring on the control area #0 assuming that the selected SS/PBCH block and the DMRS (Demodulation RS (Reference Signal)) transmitted in the control area #0 are in Quasi Co Location (QCL). The system information can be received by the downlink control information transmitted in area # 0. The terminal can obtain RACH (Random Access Channel) related configuration information necessary for initial access from the received system information. In consideration of the PBCH index, the PRACH (Physical RACH) can be transmitted to the base station, and the base station receiving the PRACH can obtain information on the SS/PBCH block index selected by the terminal. Among them, it can be seen that a block is selected, and the control region #0 corresponding to (or associated with) the SS/PBCH block selected by the UE is monitored.

Hereinafter, downlink control information (hereinafter referred to as DCI) in a next-generation mobile communication system (5G or NR system) will be described in detail.

Uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink data channel (Physical Downlink Shared Channel, PDSCH)) in a next-generation mobile communication system (5G or NR system) Scheduling information for may be delivered from the base station to the terminal through DCI. The UE may monitor a DCI format for fallback and a DCI format for non-fallback for PUSCH or PDSCH. The fallback DCI format may be composed of a fixed field that is predetermined between the base station and the terminal, and the DCI format for non-fallback may include a configurable field.

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

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

DCI format 0_0 may be used as a fallback DCI for scheduling a PUSCH, and in this case, the CRC may be scrambled with C-RNTI. In one embodiment, the DCI format 0_0 in which CRC is scrambled with C-RNTI may include information as shown in [Table 3] below.

[Table 3]

DCI format 0_1 may be used as a non-fallback DCI for scheduling a PUSCH, and in this case, the CRC may be scrambled with C-RNTI. In one embodiment, the DCI format 0_1 in which CRC is scrambled with C-RNTI may include information as shown in [Table 4] below.

[Table 4]

DCI format 1_0 may be used as a fallback DCI for scheduling a PDSCH, and in this case, the CRC may be scrambled with C-RNTI. In an embodiment, the DCI format 1_0 in which CRC is scrambled with C-RNTI may include information as shown in [Table 5] below.

[Table 5]

DCI format 1_1 may be used as a non-fallback DCI for scheduling the PDSCH, and in this case, the CRC may be scrambled with C-RNTI. In one embodiment, the DCI format 1_1 in which CRC is scrambled by C-RNTI may include information as shown in [Table 6] below.

[Table 6]

FIG. 4 is a diagram for describing a control region setting of a downlink control channel in a next generation mobile communication system according to an embodiment of the present disclosure. That is, FIG. 4 is a diagram illustrating an embodiment of a control region (Control Resource Set, CORESET) through which a downlink control channel is transmitted in a 5G wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 4, FIG. 4 shows two control regions (control region #1 (4-01) within one slot (4-20) in a frequency axis and a UE bandwidth part (4-10) as a frequency axis. ), control area #2 (4-02)) is set. The control regions 4-01 and 4-02 may be set in a specific frequency resource 4-03 within the entire terminal bandwidth part 4-10 on the frequency axis. The control regions 4-01 and 4-02 may be set as one or a plurality of OFDM symbols on the time axis, which may be defined as a control region length (Control Resource Set Duration, 4-04). Referring to FIG. 4, control region #1 (4-01) may be set to a control region length of 2 symbols, and control region #2 (4-02) may be set to control region length of 1 symbol.

In the control region in the above-described next-generation mobile communication system (5G or NR system), the base station provides higher layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling) to the terminal. It can be set by doing. Setting a control region to a terminal means providing information such as a control region identifier, a frequency position of the control region, and a symbol length of the control region. For example, the setting of the control region may include information as shown in [Table 7] below.

[Table 7]

In [Table 7], the tci-StatesPDCCH (hereinafter referred to as'TCI state') configuration information is one or more SSs (Synchronization) in a relationship between a Demodulation Reference Signal (DMRS) and a Quasi Co Located (QCL) transmitted in the corresponding control region. Signal)/PBCH (Physical Broadcast Channel) block (Block) index or CSI-RS (Channel State Information Reference Signal) index information may be included. It may also include information on what kind of relationship the QCL relationship is. For example, the setting of the TCI state may include information as shown in [Table 8] below.

[Table 8]

Referring to the TCI state setting, a cell index and/or a BWP index and a QCL type of a reference RS may be set together with an index of a reference RS having a QCL relationship, that is, an SS/PBCH block index or a CSI-RS index. The QCL type indicates channel characteristics that are assumed to be shared between the reference RS and the control region DMRS, and examples of possible QCL types are as follows.

- QCL typeA: Doppler shift, Doppler spread, average delay, delay spread. QCL typeB: Doppler shift, Doppler spread.

- QCL typeC: Doppler shift, average delay.

- QCL typeD: Spatial Rx parameter.

The TCI state can be similarly set for not only the control region DMRS but also other target RSs, such as PDSCH DMRS and CSI-RS, but detailed descriptions are omitted in order not to obscure the subject matter of the description.

5 is a diagram illustrating a structure of a downlink control channel of a next generation mobile communication system according to an embodiment of the present disclosure. That is, FIG. 5 is a diagram illustrating an example of a basic unit of time and frequency resources constituting a downlink control channel that can be used in 5G according to an embodiment of the present disclosure.

Referring to FIG. 5, a basic unit of time and frequency resources constituting a control channel may be defined as a Resource Element Group (REG, 5-03). REG (5-03) may be defined as 1 OFDM symbol (5-01) on the time axis and 1 Physical Resource Block (PRB, 5-02) on the frequency axis, that is, 12 subcarriers. The base station may configure a downlink control channel allocation unit by concatenating the REG (5-03).

As shown in FIG. 5, when a basic unit to which a downlink control channel is allocated in 5G is a control channel element (CCE, 5-04), 1 CCE (5-04) is a plurality of REGs (5-03). It can be composed of. For example, the REG (5-03) shown in FIG. 5 may be composed of 12 REs, and if 1 CCE (5-04) is composed of 6 REGs (5-03), 1 CCE (5-04) ) Can be composed of 72 REs. When a downlink control region is set, the corresponding region may be composed of a plurality of CCEs (5-04), and a specific downlink control channel is one or more CCEs (5) according to an aggregation level (AL) within the control region. -04) can be mapped and transmitted. CCEs 5-04 in the control area are classified by number, and the number of CCEs 5-04 can be assigned according to a logical mapping method.

The basic unit of the downlink control channel shown in FIG. 5, that is, the REG (5-03), may include both REs to which DCI is mapped and a region to which the DMRS 5-05, which is a reference signal for decoding them, is mapped. have. As shown in FIG. 5, three DMRSs 5-05 may be transmitted within 1 REG (5-03). The number of CCEs required to transmit the PDCCH may be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and the number of different CCEs indicates link adaptation of the downlink control channel. Can be used to implement. For example, when AL=L, one downlink control channel may be transmitted through L CCEs.

The UE needs to detect a signal without knowing the information on the downlink control channel, and a search space indicating a set of CCEs may be defined for blind decoding. The search space is a set of downlink control channel candidates (Candidates) consisting of CCEs to which the UE should attempt decoding on a given aggregation level. Since there are various aggregation levels that make one bundle with 1, 2, 4, 8, and 16 CCEs, the terminal may have a plurality of search spaces. The search space set may be defined as a set of search spaces at all set aggregation levels.

The search space may be classified into a common search space and a UE-specific search space. According to an embodiment of the present disclosure, terminals of a certain group or all terminals may examine a common search space of a PDCCH in order to receive cell-common control information such as dynamic scheduling or paging message for system information.

For example, the UE may receive PDSCH scheduling allocation information for transmission of SIB including cell operator information, etc. by examining the common search space of the PDCCH. In the case of a common search space, since a certain group of UEs or all UEs must receive a PDCCH, the common search space may be defined as a predetermined set of CCEs. Meanwhile, the UE may receive scheduling allocation information for UE-specific PDSCH or PUSCH by examining UE-specific search space of the PDCCH. The terminal-specific search space can be defined terminal-specifically as a function of the identity of the terminal and various system parameters.

In 5G, the parameter for the search space for the PDCCH may be set from the base station to the terminal by higher layer signaling (eg, SIB, MIB, RRC signaling). For example, the base station has the number of PDCCH candidates at each aggregation level L, a monitoring period for a search space, a monitoring occasion in a symbol unit in a slot for a search space, a search space type (common search space or a terminal-specific search space), The combination of the DCI format and RNTI to be monitored in the search space, and the control region index to monitor the search space can be set to the terminal. For example, the above-described setting may include information as shown in [Table 9] below.

[Table 9]

The base station may set one or a plurality of search space sets to the terminal based on the configuration information. According to an embodiment of the present disclosure, the base station may set search space set 1 and search space set 2 to the terminal, and set to monitor DCI format A scrambled with X-RNTI in search space set 1 in a common search space. In addition, DCI format B scrambled with Y-RNTI in search space set 2 may be set to be monitored in a UE-specific search space.

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

In the common search space, the 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, the 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 can follow the definitions and uses as follows.

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

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

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

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

P-RNTI (Paging RNTI): PDSCH scheduling for paging transmission

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

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

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

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

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

In one embodiment, the DCI formats described above may be defined as shown in [Table 10] below.

[Table 10]

According to an embodiment of the present disclosure, in 5G, a plurality of search space sets may be set with different parameters (eg, parameters in Table 8). Accordingly, the set of search space sets monitored by the terminal may vary at each time point. For example, if search space set #1 is set to X-slot period, search space set #2 is set to Y-slot period, and X and Y are different, the terminal searches for search space set #1 in a specific slot. Both 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.

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

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

The number of PDCCH candidates that can be monitored per slot may not exceed ^{M μ.} M ^μ may be defined as the maximum number of PDCCH candidate groups per slot in a cell set to a subcarrier interval of 15·2 ^{μ kHz, and may be defined as shown in [Table 11] below.}

[Table 11]

[Condition 2: Limit the maximum number of CCEs]

The number of CCEs constituting the total search space per slot (here, the total search space may mean the entire CCE set corresponding to the union region of a plurality of search space sets) may not exceed ^{C μ.} C ^μ may be defined as the maximum number of CCEs per slot in a cell set to a subcarrier interval of 15·2 ^{μ kHz, and may be defined as shown in [Table 12] below.}

[Table 12]

For convenience of explanation, a situation in which both conditions 1 and 2 are satisfied at a specific point in time may be exemplarily defined as “condition A”. Therefore, not satisfying the condition A may mean not satisfying at least one of the above-described conditions 1 and 2.

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

According to an embodiment of the present disclosure, the following method may be followed as a method of selecting some search spaces from among the entire set of search spaces.

[Method 1]

If the condition A for the PDCCH is not satisfied at a specific point in time (slot),

The terminal (or the base station) may preferentially select a search space set in which a search space type is set as a common search space among search space sets existing at a corresponding time point over a search space set set as a terminal-specific search space.

When all search space sets set as common search spaces are selected (i.e., when condition A is satisfied even after selecting all search spaces set as common search spaces), the terminal (or base station) is a terminal-specific search space You can select the search space sets set to. In this case, when there are a plurality of search space sets set as a terminal-specific search space, a search space set having a low search space set index may have a higher priority. In consideration of the priority, the UE or the base station may select UE-specific search space sets within a range in which condition A is satisfied.

Below, time and frequency resource allocation methods for data transmission in NR are described.

In NR, in addition to allocation of a frequency axis resource candidate through BWP indication, detailed frequency domain resource allocation (FD-RA) methods as follows may be provided.

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

Specifically, FIG. 6 shows three frequency axis resource allocation methods of type 0 (6-00), type 1 (6-05), and dynamic switch (6-10) that can be set through an upper layer in NR. Show them.

6, if the UE is configured to use only resource type 0 through higher layer signaling (6-00), some downlink control information (DCI) for allocating a PDSCH to the UE is NRBG It has a bitmap composed of bits. Conditions for this will be described later. At this time, NRBG means the number of resource block groups (RBG) determined as shown in [Table 13] below according to the BWP size allocated by the BWP indicator and the upper layer parameter rbg-Size, and according to the bitmap. Data is transmitted to the RBG indicated by 1.

[Table 13]

개의 비트들로 구성되는 주파수 축 자원 할당 정보를 가진다. 이를 위한 조건은 차후 다시 설명된다. 기지국은 이를 통하여 starting VRB(6-20)와 이로부터 연속적으로 할당되는 주파수 축 자원의 길이(6-25)를 설정할 수 있다.If the UE is configured to use only resource type 1 through higher layer signaling (6-05), some DCIs that allocate PDSCH to the UE are

It has frequency axis resource allocation information consisting of three bits. The conditions for this will be described again later. Through this, the base station may set the starting VRB 6-20 and the length of the frequency axis resources continuously allocated therefrom (6-25).

If the UE is configured to use both resource type 0 and resource type 1 through higher layer signaling (6-10), some DCIs that allocate PDSCH to the UE are payload for setting resource type 0 (6-15) It has frequency axis resource allocation information consisting of bits of the larger value (6-35) among payloads (6-20, 6-25) for setting resource type 1. The conditions for this will be described again later. At this time, one bit may be added to the first part (MSB) of the frequency axis resource allocation information within the DCI, and if the corresponding bit is 0, it indicates that resource type 0 is used, and if it is 1, it indicates that resource type 1 is used. Can be.

Hereinafter, a method of allocating time domain resources 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 data channel (Physical Downlink Shared Channel, PDSCH) and an uplink data channel (Physical Uplink Shared Channel, PUSCH) to the UE, and higher layer signaling (e.g. For example, RRC signaling) can be set. For the PDSCH, a table consisting of maxNrofDL-Allocations=16 entries can be set, and for the PUSCH, a table consisting of maxNrofUL-Allocations=16 entries can be set. In one embodiment, the time domain resource allocation information includes PDCCH-to-PDSCH slot timing (corresponds to the time interval in units of slots between the time when the PDCCH is received and the time when the PDSCH scheduled by the received PDCCH is transmitted, expressed as K0. ), PDCCH-to-PUSCH slot timing (corresponds 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 on the location and length of the scheduled start symbol, the PDSCH or PUSCH mapping type, and the like may be included. For example, information such as [Table 14] or [Table 15] below may be notified from the base station to the terminal.

[Table 14]

[Table 15]

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

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

,

), 스케줄링 오프셋(scheduling offset)(K₀) 값, 그리고 DCI를 통하여 동적으로 지시되는 한 slot 내 OFDM symbol 시작 위치(7-00)와 길이(7-05)에 따라 PDSCH 자원의 시간 축 위치를 지시할 수 있다. Referring to FIG. 7, the base station is a subcarrier spacing (SCS) of a data channel and a control channel set using an upper layer (

,

), the scheduling offset (K ₀ ) value, and the time axis position of the PDSCH resource according to the OFDM symbol start position (7-00) and length (7-05) within a slot dynamically indicated through DCI. I can instruct.

8 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.

), 데이터와 제어를 위한 슬롯 번호(slot number)가 같으므로, 기지국 및 단말은 미리 정해진 슬롯 오프셋(slot offset) K₀에 맞추어, 스케줄링 오프셋(scheduling offset)이 발생하는 것을 알 수 있다. 반면, 데이터 채널 및 제어 채널의 서브캐리어 간격이 다른 경우 (8-05,

), 데이터와 제어를 위한 슬롯 번호(slot number)가 다르므로, 기지국 및 단말은 PDCCH의 서브캐리어 간격을 기준으로 하여, 미리 정해진 슬롯 오프셋(slot offset) K₀에 맞추어 스케줄링 오프셋(scheduling offset)이 발생하는 것을 알 수 있다.Referring to FIG. 8, when the subcarrier spacing of the data channel and the control channel is the same (8-00,

), since the slot number for data and control are the same, the base station and the terminal can know that a scheduling offset occurs in accordance with _{a predetermined slot offset K 0.} On the other hand, if the subcarrier spacing of the data channel and the control channel is different (8-05,

), since the slot number for data and control is different, the base station and the terminal have a scheduling offset according to _{a predetermined slot offset K 0 based on the subcarrier interval of the PDCCH.} You can see what happens.

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

The base station may deliver a UE capability inquiry message requesting capability report to the UE in the connected state. In the message, the base station may include a UE capability request for each RAT type. The request for each RAT type may include requested frequency band information. In addition, the UE capability request message may request a plurality of RAT types in one RRC message container, or may include a UE capability request message including a request for each RAT type multiple times to the UE. That is, the UE capability request is repeated a plurality of times, and the UE may report a plurality of times by configuring a corresponding UE capability information message. In the next-generation mobile communication system, it is possible to request terminal capability for MR-DC including NR, LTE, and EN-DC. In addition, the UE capability request message is generally transmitted initially after the terminal is connected to the base station, but can be requested under any conditions when the base station is required.

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 the UE capability in the NR system.

One. If the UE receives a list of LTE and/or NR bands as a UE capability request from the base station, the UE configures a band combination (BC) for EN-DC and NR stand alone (SA). That is, a BC candidate list for EN-DC and NR SA is constructed based on the bands requested by the base station as FreqBandList. In addition, the priorities of the 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 “eutra” flag, the UE completely removes the NR SA BCs from the configured BC candidate list. This operation may occur only when the LTE base station (eNB) requests “eutra” capability.

3. Thereafter, the UE removes fallback BCs from the BC candidate list configured in the above step. Here, fallback BC corresponds to a case in which a band corresponding to at least one SCell is removed from a super set BC, and can be omitted because the super set BC can already cover the fallback BC. This step also applies to MR-DC, that is, to LTE bands. BCs remaining after this stage are the final “list of candidate BCs”.

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 constructs a supportedBandCombinationList in a predetermined order. That is, the UE configures the BC and UE capabilities to be reported in accordance with the order of the preset rat-Type. (nr -> eutra-nr -> eutra). In addition, featureSetCombination for the configured supportedBandCombinationList is configured, and a list of “candidate feature set combinations” is formed from the candidate BC list from which the list for fallback BC (including the capability of the same or lower level) has been removed. The “candidate feature set combination” includes both a feature set combination for NR and EUTRA-NR BC, and can be obtained from a feature set combination of UE-NR-Capabilities and UE-MRDC-Capabilities containers.

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

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

In NR, the UE transmits uplink control information (UCI) to the base station through a physical uplink control channel (PUCCH). The control information includes HARQ-ACK indicating success or failure of demodulation/decoding for a transport block (TB) received by the UE through the PDSCH, and a scheduling request (SR) for requesting resource allocation from the UE to the PUSCH base station for uplink data transmission. ), at least one of channel state information (CSI), which is information for reporting the channel state of the terminal, may be included.

The PUCCH resource can be largely divided into long PUCCH and short PUCCH according to the length of the allocated symbol. In NR, a long PUCCH has a length of 4 symbols or more in a slot, and a short PUCCH has a length of 2 symbols or less in a slot.

In more detail with respect to the Long PUCCH, the long PUCCH may be used for the purpose of improving uplink cell coverage, and thus may be transmitted in a DFT-S-OFDM scheme, which is a single carrier transmission rather than OFDM transmission. Long PUCCH supports transmission formats such as PUCCH format 1, PUCCH format 3, and PUCCH format 4 depending on the number of supportable control information bits and whether terminal multiplexing through Pre-DFT OCC support at the front end of the IFFT is supported.

First, PUCCH format 1 is a DFT-S-OFDM-based long PUCCH format capable of supporting up to 2 bits of control information, and uses frequency resources as much as 1 RB. The control information may be composed of a combination of HARQ-ACK and SR or each. In PUCCH format 1, an OFDM symbol including a DeModulation Reference Signal (DMRS) that is a demodulation reference signal (or a reference signal) and an OFDM symbol including UCI are repeatedly configured.

For example, when the number of transmission symbols of PUCCH format 1 is 8 symbols, the first start symbol of 8 symbols is sequentially composed of DMRS symbols, UCI symbols, DMRS symbols, UCI symbols, DMRS symbols, UCI symbols, DMRS symbols, and UCI symbols. It will be. The DMRS symbol is spread using an orthogonal code (or orthogonal sequence or spreading code, w_i(m)) on the time axis to a sequence corresponding to the length of 1RB on the frequency axis within one OFDM symbol, and is transmitted after IFFT is performed. .

The UCI symbol is modulated with 1-bit control information in BPSK and 2-bit control information in QPSK to generate d(0), and the generated d(0) is multiplied by a sequence corresponding to the length of 1 RB on the frequency axis to scramble and scramble. The sequence is spread using an orthogonal code (or an orthogonal sequence or spreading code, w_i(m)) on the time axis, and the IFFT is performed and then transmitted.

The UE generates a sequence based on the group hopping or sequence hopping set and set ID set as a higher signal from the base station, and cyclic shifts the generated sequence with an initial CS (cyclic shift) value set as a higher signal to a length of 1 RB. Generate the corresponding sequence.

와 같이 결정되며, 구체적으로 다음 [표 16]와 같이 주어진다. i는 스프레딩 부호 그 자체의 인덱스를 의미하며, m은 스프레딩 부호의 element들의 인덱스를 의미한다. 여기서 [표 16] 내에 [ ]안의 숫자들은

을 의미하며, 가령 스프레딩 부호의 길이가 2이고, 설정된 스프레딩 부호의 인덱스 i=0인 경우, 스프레딩 부호 w_i(m)은

,

이 되어서 w_i(m)=[1 1]이 된다.w_i(m) is given the length of the spreading code (N _SF)

It is determined as shown in [Table 16] below. i means the index of the spreading code itself, and m means the index of the elements of the spreading code. Here, the numbers in [] in [Table 16] are

For example, if the length of the spreading code is 2 and the index i of the set spreading code is 0, the spreading code w_i(m) is

,

And w_i(m) = [1 1].

[Table 16]

Next, PUCCH format 3 is a DFT-S-OFDM based long PUCCH format capable of supporting more than 2 bits of control information, and the number of RBs used can be set through an upper layer. The control information may consist of a combination of HARQ-ACK, SR, and CSI, or each. In PUCCH format 3, the position of the DMRS symbol is presented in [Table 17] according to whether frequency hopping in the slot and whether additional DMRS symbols are set.

[Table 17]

For example, when the number of transmission symbols of the PUCCH format 3 is 8 symbols, the first start symbol of the 8 symbols starts with 0, and the DMRS is transmitted in the first symbol and the fifth symbol. The above table is applied in the same manner to the DMRS symbol position of PUCCH format 4.

Next, PUCCH format 4 is a DFT-S-OFDM-based long PUCCH format capable of supporting more than 2 bits of control information, and uses frequency resources as much as 1 RB. The control information may consist of a combination of HARQ-ACK, SR, and CSI, or each. The difference between PUCCH format 4 and PUCCH format 3 is that in the case of PUCCH format 4, PUCCH format 4 of multiple terminals can be multiplexed within one RB. It is possible to multiplex PUCCH format 4 of a plurality of terminals through application of Pre-DFT OCC to control information in the front of the IFFT. However, the number of transmittable control information symbols of one terminal decreases according to the number of multiplexed terminals. The number of multiplexable terminals, that is, the number of different OCCs that can be used may be 2 or 4, and the number of OCCs and the OCC index to be applied may be set through a higher layer.

Next, the short PUCCH will be described. Short PUCCH can be transmitted in both a downlink centric slot and an uplink centric slot. In general, the last symbol of the slot or an OFDM symbol at the rear (for example, the last OFDM symbol or It is transmitted in the second OFDM symbol from the last, or the last 2 OFDM symbols). Of course, it is also possible to transmit a short PUCCH at any position in the slot. In addition, the short PUCCH may be transmitted using one OFDM symbol or two OFDM symbols. Short PUCCH can be used to shorten a delay time compared to long PUCCH in a situation where uplink cell coverage is good, and is transmitted in a CP-OFDM scheme.

Short PUCCH supports transmission formats such as PUCCH format 0 and PUCCH format 2 according to the number of supportable control information bits. First, PUCCH format 0 is a short PUCCH format capable of supporting control information of up to 2 bits, and uses frequency resources of 1 RB. The control information may be composed of a combination of HARQ-ACK and SR or each. PUCCH format 0 does not transmit DMRS, but transmits only sequences mapped to 12 subcarriers along the frequency axis within one OFDM symbol. The terminal generates a sequence based on the group hopping or sequence hopping configuration and set ID set as a higher signal from the base station, and the final CS value obtained by adding different CS values according to whether ACK or NACK to the indicated initial cyclic shift (CS) value. As a result, the generated sequence is cyclic shifted, mapped to 12 subcarriers, and transmitted.

For example, if HARQ-ACK is 1 bit, as shown in Table 18 below, if it is ACK, 6 is added to the initial CS value to generate the final CS, and if it is NACK, 0 is added to the initial CS to generate the final CS. The CS value 0 for NACK and 6, the CS value for ACK are defined in the standard, and the UE always transmits 1-bit HARQ-ACK by generating PUCCH format 0 according to the value.

[Table 18]

For example, if HARQ-ACK is 2 bits, 0 is added to the initial CS value if (NACK, NACK) as in the following [Table 19], and 3 is added to the initial CS value if (NACK, ACK), and (ACK, ACK ), 6 is added to the initial CS value, and 9 is added to the initial CS value if (ACK, NACK). The CS value 0 for (NACK, NACK), 3 for the CS value for (NACK, ACK), 6 for the CS value for (ACK, ACK), and 9 for the CS value for (ACK, NACK) are defined in the standard. , The terminal always transmits a 2-bit HARQ-ACK by generating PUCCH format 0 according to the value.

If the final CS value exceeds 12 by the CS value added according to ACK or NACK to the initial CS value, since the length of the sequence is 12, modulo 12 is applied to the final CS value.

[Table 19]

Next, PUCCH format 2 is a short PUCCH format that supports control information of more than 2 bits, and the number of RBs used can be set through an upper layer. The control information may consist of a combination of HARQ-ACK, SR, and CSI, or each. PUCCH format 2 has an index of #1, #4, #7, and #10 when the position of a subcarrier in which the DMRS is transmitted within one OFDM symbol is the index of the first subcarrier as #0 as shown in FIG. It is fixed to the subcarrier. The control information is mapped to the remaining subcarriers excluding the subcarrier where the DMRS is located through a modulation process after channel coding.

In summary, values that can be set for each of the above-described PUCCH formats and their ranges can be summarized as shown in Table 20 below. If the value does not need to be set in the following table, it is indicated as N.A.

[Table 20]

Meanwhile, in order to improve uplink coverage, multi-slot repetition may be supported for PUCCH formats 1, 3, and 4, and PUCCH repetition may be set for each PUCCH format.

Next, the PUCCH resource configuration of the base station or the terminal will be described. The base station can configure PUCCH resources for each BWP through an upper layer for a specific terminal. The setting can be as shown in the following [Table 21].

[Table 21]

According to the above table, one or a plurality of PUCCH resource sets in the PUCCH resource setting for a specific BWP may be set, and a maximum payload value for UCI transmission may be set in some of the PUCCH resource sets. Each PUCCH resource set may include one or more PUCCH resources, and each PUCCH resource may belong to one of the above-described PUCCH formats.

For the PUCCH resource set, the maximum payload value of the first PUCCH resource set may be fixed to 2 bits, and thus the corresponding value may not be set separately through an upper layer or the like. When the remaining PUCCH resource set is configured, the index of the corresponding PUCCH resource set may be set in ascending order according to the maximum payload value, and the maximum payload value may not be set in the last PUCCH resource set. The upper layer configuration for the PUCCH resource set may be as shown in Table 22 below.

[Table 22]

The resourceList parameter of the table may include IDs of PUCCH resources belonging to the PUCCH resource set.

If at the time of initial access or when the PUCCH resource set is not set, a PUCCH resource set as shown in [Table 22], which is composed of a plurality of cell-specific PUCCH resources in the initial BWP, may be used. The PUCCH resource to be used for initial access in this PUCCH resource set may be indicated through SIB1.

[Table 23]

The maximum payload of each PUCCH resource included in the PUCCH resource set may be 2 bits in case of PUCCH format 0 or 1, and may be determined by the symbol length, the number of PRBs, and the maximum code rate in the case of the remaining formats. The above-described symbol length and number of PRBs may be set for each PUCCH resource, and the maximum code rate may be set for each PUCCH format.

Next, PUCCH resource selection for UCI transmission will be described. In the case of SR transmission, a PUCCH resource for an SR corresponding to schedulingRequestID may be configured through a higher layer as shown in Table 24 below. The PUCCH resource may be a resource belonging to PUCCH format 0 or PUCCH format 1.

[Table 24]

For the set PUCCH resource, a transmission period and an offset are set through the periodicityAndOffset parameter of [Table 24]. When there is uplink data to be transmitted by the UE at a time corresponding to the set period and offset, the corresponding PUCCH resource is transmitted, otherwise the corresponding PUCCH resource may not be transmitted.

In the case of CSI transmission, a PUCCH resource for transmitting a periodic or semi-persistent CSI report through PUCCH may be set in the pucch-CSI-ResourceList parameter as shown in Table 23 below. The parameter contains a list of PUCCH resources for each BWP for the cell or CC to which the corresponding CSI report is to be transmitted. The PUCCH resource may be a resource belonging to PUCCH format 2 or PUCCH format 3 or PUCCH format 4.

[Table 25]

For the PUCCH resource, a transmission period and an offset are set through reportSlotConfig of [Table 23].

In the case of HARQ-ACK transmission, a resource set of PUCCH resources to be transmitted is first selected according to the payload of the UCI including the corresponding HARQ-ACK. That is, a PUCCH resource set having a minimum payload that is not smaller than the UCI payload is selected. Next, the PUCCH resource in the PUCCH resource set can be selected through the PUCCH resource indicator (PRI) in the DCI that schedules the TB corresponding to the corresponding HARQ-ACK, and the PRI is the PUCCH specified in [Table 5 ] or [Table 6]. May be a resource indicator. The relationship between the PRI and PUCCH resources selected from the PUCCH resource set may be as shown in Table 26 below.

[Table 26]

If the number of PUCCH resources in the selected PUCCH resource set is greater than 8, the PUCCH resource may be selected by the following equation.

[Equation 1]

는 PUCCH resource set 내 선택된 PUCCH resource의 인덱스,

는 PUCCH resource set에 속한 PUCCH resource의 개수,

는 PRI 값,

는 수신 DCI가 속한 CORESET p의 총 CCE 수,

는 수신 DCI에 대한 첫번째 CCE 인덱스를 가리킨다.In the above equation

Is the index of the selected PUCCH resource in the PUCCH resource set,

Is the number of PUCCH resources belonging to the PUCCH resource set,

Is the PRI value,

Is the total number of CCEs in CORESET p to which the receiving DCI belongs,

Indicates the first CCE index for the received DCI.

슬롯 이후이다. 상기

값의 후보는 상위 레이어로 설정되며, 보다 구체적으로 [표 21]에 명시된 PUCCH-Config 내 dl-DataToUL-ACK 파라미터에 설정된다. 이들 후보 중 하나의

값이 상기 TB를 스케줄하는 DCI 내 PDSCH-to-HARQ feedback timing indicator에 의해 선택될 수 있으며 이 값은 상기 [표 5] 또는 [표 6]에 명시된 값일 수 있다. 한편, 상기

값의 단위는 슬롯 단위이거나 서브슬롯 단위일 수 있다. 여기서 서브슬롯이란 슬롯보다 작은 길이의 단위로서 하나 또는 복수개의 심볼이 하나의 서브슬롯을 구성할 수 있다.The time point at which the corresponding PUCCH resource is transmitted is from the TB transmission corresponding to the HARQ-ACK

After the slot. remind

The value candidate is set to the upper layer, and more specifically, is set in the dl-DataToUL-ACK parameter in the PUCCH-Config specified in [Table 21]. One of these candidates

A value may be selected by the PDSCH-to-HARQ feedback timing indicator in the DCI scheduling the TB, and this value may be a value specified in [Table 5 ] or [Table 6]. Meanwhile, above

The unit of the value may be a slot unit or a subslot unit. Here, a subslot is a unit of a length smaller than that of a slot, and one or a plurality of symbols may constitute one subslot.

Next, a case where two or more PUCCH resources are located in one slot will be described. The UE can transmit UCI through one or two PUCCH resources in one slot or subslot, and when UCI is transmitted through two PUCCH resources in one slot/subslot i) Each PUCCH resource does not overlap in units of symbols, ii) At least one PUCCH resource may be a short PUCCH. Meanwhile, the UE may not expect to transmit a plurality of PUCCH resources for HARQ-ACK transmission within one slot.

Next, it describes the PUCCH transmission procedure in case two or more PUCCH resources overlap. When two or more PUCCH resources overlap, one of the overlapping PUCCH resources is selected or a new PUCCH resource may be selected according to the above-described condition, that is, the condition that the transmitted PUCCH resource should not overlap in symbol units. In addition, the UCI payload transmitted through the overlapping PUCCH resource may be multiplexed and transmitted or some may be dropped. First, Case 1. When multi-slot repetition is not set in PUCCH resource and Case 2. Multi-slot repetition is set.

When the PUCCH resource is overlapped for Case 1, it is divided into Case 1-1) when two or more PUCCH resources for HARQ-ACK transmission are overlapped and Case 1-2) the remaining cases.

A case corresponding to Case 1-1) is illustrated in FIG. 9.

값(9-50, 9-51)에 대응하는 상향링크 슬롯이 동일한 경우, 해당 PDCCH에 대응하는 PUCCH resource들은 서로 overlap된다고 볼 수 있다. 9 is a diagram illustrating a case of overlapping a plurality of PUCCH resources for HARQ-ACK transmission for PDSCH when multi-slot repetition is not configured according to an embodiment of the present disclosure. Referring to FIG. 9, PDSCH For two or more different scheduled PDCCHs (9-10, 9-11), if the transmission slot of the PUCCH resource corresponding to each PDCCH is the same, the corresponding PUCCH resource can be seen as overlapping each other. That is, a number of PDCCHs indicated

If the uplink slots corresponding to the values (9-50, 9-51) are the same, PUCCH resources corresponding to the corresponding PDCCH can be viewed as overlapping each other.

At this time, among the PUCCH resources indicated by the PRIs (9-40, 9-41) in the PDCCH, a PUCCH resource selected based on the PRI (9-41) corresponding to the PDCCH (9-11) transmitted at the latest time point Only (9-31) is selected and transmitted. Therefore, all HARQ-ACK information for PDSCH (9-21) through the selected PUCCH resource (9-31), and HARQ-ACK information for other PUCCH (9-30) overlapping with the PUCCH resource (9-31) Is encoded by a predefined HARQ-ACK codebook and then transmitted.

Next, corresponding to Case 1-2), if the PUCCH resource for HARQ-ACK transmission and the PUCCH resource for SR and/or CSI transmission are overlapped or a plurality of PUCCH resources for SR and/or CSI transmission are overlapped Explain the case. In the above case, when a plurality of PUCCH resources transmitted in the same slot overlap more than one symbol in the time axis, it is defined that the corresponding PUCCH resource is overlapped, and whether or not multiplexing of UCIs in these resources can be summarized as shown in Table 27 below.

[Table 27]

According to the above table, if the HARQ-ACK is overlapped between the PUCCH resource is transmitted, or if the overlap between the PUCCH SR and CSI are transmitted, these UCIs are always multiplexed.

On the other hand, when each PUCCH resource in which SR and HARQ-ACK are transmitted overlap, that is, in the case of Case 1-2-1, whether or not UCI multiplexing is performed according to the format of the PUCCH resource is divided as follows.

-SR on PUCCH format 0 + HARQ-ACK on PUCCH format 1: SR is dropped and only HARQ-ACK is transmitted

-In the other cases: SR and HARQ-ACK are both multiplexed

In addition, the remaining cases corresponding to Case 1-2-2, that is, when overlapping between the PUCCH resource in which HARQ-ACK and CSI are transmitted, or when overlapping between a plurality of PUCCH resources in which CSI is transmitted, the multiplexing of these UCIs is higher You can follow the layer settings. Also, whether to multiplex between HARQ-ACK and CSI and whether to multiplex between multiple CSIs can be independently performed.

For example, whether or not HARQ-ACK and CSI are multiplexed may be set through simultaneousHARQ-ACK-CSI parameters for PUCCH formats 2, 3, and 4, and the corresponding parameters may all be set to the same value for the PUCCH format. If the multiplexing is set not to be performed through the above parameters, only HARQ-ACK is transmitted and the overlapping CSI may be dropped. In addition, whether or not multiplexing between multiple CSIs is performed may be set through a multi-CSI-PUCCH-ResourceList parameter in PUCCH-Config. That is, when the multi-CSI-PUCCH-ResourceList parameter is set, inter-CSI multiplexing may be performed. Otherwise, only a PUCCH corresponding to a CSI having a higher priority may be transmitted according to the inter-CSI priority.

When UCI multiplexing is performed as described above, the selection method of the PUCCH resource to transmit the corresponding UCI resource and the multiplexing method may be different according to the information of the overlapped UCI and the format of the PUCCH resource, which can be summarized as follows [Table 28] I can.

[Table 28]

Each option in the above table is as follows.

-Option 1: different PUCCH resource selection according to the SR value of the HARQ-ACK PUCCH resource and overlapped SR PUCCH resource. That is, if the SR value is positive, PUCCH resource for SR is selected, and if the SR value is negative, PUCCH resource for HARQ-ACK is selected. HARQ-ACK information is transmitted to the selected PUCCH resource.

-Option 2: HARQ-ACK information and SR information are multiplexed and transmitted to PUCCH resource for HARQ-ACK transmission.

-Option 3: multiplexed SR information and HARQ-ACK information to PUCCH resource for CSI transmission and transmitted.

-Option 4: PUCCH resource transmission for overlapping between HARQ-ACK-Detailed operation is described in the case 1-1).

-Option 5: PUCCH resource for HARQ-ACK corresponding to the PDSCH scheduled as PDCCH and PUCCH resource for CSI transmission are overlapped, and if multiplexing between HARQ-ACK and CSI is set to the upper layer, PUCCH resource for HARQ-ACK HARQ-ACK information and CSI information are multiplexed and transmitted.

-Option 6: PUCCH resource for HARQ-ACK corresponding to SPS (semi-persistent scheduling) PDSCH and PUCCH resource for CSI transmission overlap, and when multiplexing between HARQ-ACK and CSI is set as an upper layer, PUCCH for CSI transmission HARQ-ACK information and CSI information are multiplexed and transmitted to the resource.

If the PUCCH resource list for multiplexing to the upper layer, that is, multi-CSI-PUCCH-ResourceList is set, all of the multiplexed UCI payloads among the resources in the list can be transmitted, and the UCI payload after selecting one resource with the lowest index Transmit. If there is no resource capable of transmitting all the multiplexed UCI payloads in the list, the resource with the largest index is selected, and then HARQ-ACKs and CSI reports as many as the number of possible transmissions are transmitted to the corresponding resource.

-Option 7: When multiple CSI transmission PUCCH resources are overlapped and multiplexing between multiple CSIs is set to the upper layer, the PUCCH resource list for CSI multiplexing set to the upper layer, that is, multiplexed within the multi-CSI-PUCCH-ResourceList All of the UCI payloads can be transmitted, and the UCI payload is transmitted after selecting one resource with the lowest index. If there is no resource capable of transmitting all of the multiplexed UCI payloads in the list, select the resource with the largest index and transmit as many CSI reports as possible to the corresponding resource.

In the above, for the convenience of technology, the focus has been dealt with the case where two PUCCH resources overlap, but the method may be similarly applied even when three or more PUCCH resources overlap. For example, if SR+HARQ-ACK is multiplexed PUCCH resource and CSI PUCCH resource overlap, it can follow the multiplexing method between HARQ-ACK and CSI.

If it is configured not to perform multiplexing between specific UCIs, UCI with a higher priority is transmitted according to the priority in the order of HARQ-ACK> SR> CSI, and UCI with a lower priority may be dropped. When multiple CSI PUCCH resources are set not to perform multiplexing when overlapping, PUCCH corresponding to the high priority CSI is transmitted, and PUCCH corresponding to other CSI can be dropped.

Next, Case 2, that is, when multi-slot repetition is set, is divided into Case 2-1) when two or more PUCCH resources for HARQ-ACK transmission are located in the same start slot and Case 2-2) the remaining cases. Each case is shown in FIG. 10.

10 is a diagram illustrating a case in which a PUCCH resource overlaps when a multi-slot repetition is set according to an embodiment of the present disclosure.

으로 지시되는 두 PUCCH의 시작 슬롯이 동일하다면 Case 1-1)과 동일하게 단일 PUCCH resource (한 슬롯에서 가장 나중 시점에 전송되는 PUCCH), 즉 PUCCH #2가 선택될 수 있다. 따라서, 해당 PUCCH에는 PDSCH #1및 PDSCH #2에 상응하는 HARQ-ACK이 HARQ-ACK 코드북을 통해 모두 멀티플렉싱되어 전송된다. Referring to Case 2-1), when multi-slot repetition is set in the PUCCH resource for HARQ-ACK, that is, PUCCH #1 is repeatedly transmitted over multiple slots (10-30, 10-40) and PUCCH #2 is also When repeatedly transmitted over multiple slots (10-31, 10-41),

If the starting slots of the two PUCCHs indicated as are the same, a single PUCCH resource (PUCCH transmitted at the latest time in one slot), that is, PUCCH #2, may be selected in the same manner as Case 1-1). Accordingly, HARQ-ACKs corresponding to PDSCH #1 and PDSCH #2 are multiplexed and transmitted to the PUCCH through the HARQ-ACK codebook.

For the convenience of technology, a case in which a plurality of PUCCHs subjected to multi-slot repetition are overlapped is exemplified, but the same method may be applied when overlapping between the multi-slot repetition PUCCH and the PUCCH transmitted in a single slot.

Case 2-2) corresponds to a case in which a symbol unit overlap occurs between PUCCH for HARQ-ACK transmission and PUCCH for SR or CSI transmission, or between PUCCHs for multiple SR or CSI transmission. That is, when PUCCH #1 is repeatedly transmitted over multiple slots (10-50, 10-51) and PUCCH #2 is also repeatedly transmitted over multiple slots (10-60, 10-61), PUCCH #1 and PUCCH # 2 corresponds to the case where more than one symbol overlap occurs in one slot (10-70).

Between PUCCHs in which more than one symbol overlap occurs in the corresponding slot (10-70), by comparing the priority between UCIs in the PUCCH, UCIs with higher priority are transmitted, and other UCIs are dropped in the corresponding slot. At this time, the priority between UCIs follows HARQ-ACK> SR> CSI in the highest order.

In addition, when a plurality of CSI PUCCH resources overlap, the PUCCH corresponding to the high priority CSI is transmitted, and the PUCCH corresponding to the other CSI may be dropped in the corresponding slot. PUCCH transmission or drop according to the above-described priority is performed only in the slot in which the symbol unit overlap has occurred, and is not performed in other slots. That is, the PUCCH in which multi-slot repetition is set may be dropped in the slot where the symbol unit overlap occurs, but may be transmitted as set in the remaining slots.

In the above case, for convenience of technology, a case in which a plurality of PUCCHs subjected to multi-slot repetition is overlapped is exemplified, but the same method may be applied when overlapping between the multi-slot repetition PUCCH and the PUCCH transmitted in a single slot.

Next, a method of generating a HARQ-ACK codebook for transmitting HARQ-ACK in the selected PUCCH resource as described above will be described. When the PDSCH, which is the downlink data, is scheduled based on the DCI information of the PDCCH, the PDSCH is transmitted and the slot information to which the corresponding HARQ-ACK feedback is mapped, and the mapping of the uplink control channel PUCCH that carries the HARQ-ACK feedback information. Information is conveyed. Specifically, the slot interval between the downlink data PDSCH and the corresponding HARQ-ACK feedback is indicated through the PDSCH-to-HARQ_feedback timing indicator, and eight feedback timing offsets set through an upper layer (eg, RRC signaling) Either can be indicated. In addition, in order to deliver the PUCCH resource including the type of the UL control channel PUCCH to which the HARQ-ACK feedback information is mapped, the location of the start symbol, and the number of mapping symbols, one of eight resources set as an upper layer through the PUCCH resource indicator Instruct. In order to transmit HARQ-ACK information to the base station, the terminal collects and transmits HARQ-ACK feedback bits, and hereinafter, the collected HARQ-ACK feedback bits may be referred to as a combination of the HARQ-ACK codebook.

The base station may configure a Type-1 HARQ-ACK codebook that transmits HARQ-ACK feedback bits corresponding to the PDSCH that can be transmitted at a slot position of a predetermined timing to the terminal, regardless of whether the PDSCH is actually transmitted. Alternatively, the base station may configure a Type-2 HARQ-ACK codebook that manages and transmits HARQ-ACK feedback bits corresponding to the actually transmitted PDSCH through counter DAI (downlink assignment index) or total DAI to the terminal.

When the UE is configured with the Type-1 HARQ-ACK codebook, it should be transmitted through a table including information on the slot to which the PDSCH is mapped, the start symbol, the number of symbols, or length information, and the K1 candidate values, which are HARQ-ACK feedback timing information for the PDSCH. The feedback bit can be determined. The table including the start symbol, number of symbols, or length information of the PDSCH may be set as higher layer signaling or may be set as a default table. Also, the K1 candidate values may be set as default values, for example {1,2,3,4,5,6,7,8} or may be determined through higher layer signaling. The slot to which the PDSCH is mapped can be known through the K1 value when the PDSCH is transmitted in a single slot, and indicates the K1 value and the number of repetitive transmissions when the PDSCH is repeatedly transmitted in a plurality of slots. It can be known as a higher layer parameter, for example a pdsch-AggregationFactor value set in the PDSCH-Config IE in the active BWP. If the PDSCH is repeatedly transmitted in a plurality of slots, the K1 value is indicated on the basis of the last slot in the repeated transmission of the PDSCH, and the slot to which the PDSCH is mapped is the last slot to be repeatedly transmitted, that is, the slot of the pdsch-AggregationFactor th from the repeat transmission start slot. Is regarded as,

Assuming that the set of PDSCH reception candidate cases in the serving cell c is M _{A,c , M A,c} can be determined in the following [pseudo-code 1] steps.

[start pseudo-code 1]

Step 1: Initialize j to 0, M _A,c to empty set, and HARQ-ACK transmission timing index k to 0.

- Step 2: Set R as a set of rows in a table including information on a slot to which the PDSCH is mapped, a start symbol, number of symbols, or length. If the symbol to which the PDSCH indicated by each row of R is mapped is set as an uplink symbol according to the higher layer setting, the corresponding row is deleted from R.

-Step 3-1: If the UE can receive one PDSCH for unicast in one slot and R is not an empty set, k is added _{to the sets M A,c.}

-Step 3-2: If the UE can receive more than one PDSCH in one slot, R counts the maximum number of PDSCHs that can be allocated to different symbols, increases j as much as the number by 1 _{, and M A, c} Add.

- Step 4: Start over from Step 2 by increasing k by 1.

[end of pseudo-code 1]

HARQ-ACK feedback bits may be determined in the following [pseudo-code 2] steps for _{M A,c} determined by the [pseudo-code 1].

[start pseudo-code 2]

- Step 1: Initialize the HARQ-ACK reception occasion index m to 0 and the HARQ-ACK feedback bit index j to 0.

- Step 2-1: When the UE is instructed to receive HARQ-ACK bundling for codewords through higher layer signaling, not instructing to transmit CBG of PDSCH, and to receive up to two codewords through one PDSCH , j is increased by 1, and HARQ-ACK feedback bits for each codeword are configured.

- Step 2-2: When the UE is instructed to bundle HARQ-ACK for a codeword through higher layer signaling and is instructed to receive up to two codewords through one PDSCH, HARQ-ACK for each codeword The feedback bit is composed of one HARQ-ACK feedback bit through a binary AND operation.

- Step 2-3: If the UE is instructed to transmit CBG of the PDSCH through higher layer signaling and is not instructed to receive a maximum of two codewords through one PDSCH, j is increased by 1 and added to one codeword. For each of the number of CBG HARQ-ACK feedback bits are configured.

- Step 2-4: When the UE is instructed to transmit CBG of PDSCH through higher layer signaling and is instructed to receive up to two codewords through one PDSCH, j is increased by 1 and for each codeword Configure HARQ-ACK feedback bits as many as the number of CBGs.

- Step 2-5: When the UE is not instructed to transmit CBG of PDSCH through higher layer signaling and is not instructed to receive up to two codewords through one PDSCH, HARQ-ACK feedback for one codeword Make up the beat.

- Step 3: Start over from Step 2-1 by increasing m by 1.

[end of pseudo-code 2]

When the terminal is configured with the Type-2 HARQ-ACK codebook, a counter DAI (downlink assignment index) or total DAI that manages K1 candidate values, which are HARQ-ACK feedback timing information for the PDSCH, and HARQ-ACK feedback bits corresponding to the PDSCH. The feedback bit to be transmitted through is determined. K1 candidate values, which are HARQ-ACK feedback timing information for the PDSCH, are composed of a union of default values and values designated through higher layer signaling. For example, default values may be set as {1,2,3,4,5,6,7,8}.

이라 하고, 상향링크 제어 채널 PDCCH 모니터링 타이밍 m에 PDSCH를 할당한 DCI format 1_1의 total DAI를

이라 하면, 하기와 같은 [pseudo-code 3] 단계들로 Type-2 HARQ-ACK codebook을 구성할 수 있다.The counter DAI of DCI format 1_0 or DCI format 1_1 allocated by the serving cell c to the PDCCH monitoring timing m

And the total DAI of DCI format 1_1 allocated with the PDSCH to the uplink control channel PDCCH monitoring timing m

In this case, a Type-2 HARQ-ACK codebook can be configured with the following [pseudo-code 3] steps.

[Start pseudo-code 3]

-Step 1: Serving cell index c as 0, PDCCH monitoring timing m as 0, j as 0, indexes for DAI comparison V _temp , V _temp2 as 0, HARQ-ACK feedback bit set V _S as empty set reset.

- Step 2: If the PDCCH monitoring timing m is before the downlink BWP change for the serving cell c or before the uplink BWP change for the PCell, and the downlink BWP change is not triggered due to the DCI format 1_1 of the PDCCH monitoring timing m, c Excluded from serving cell set.

가 V_temp보다 작거나 같으면 j를 1 증가시키고 V_temp를

로 설정. 또한,

가 공집합일 경우 V_temp2를

로 설정하고

가 공집합이 아닐 경우 V_temp2를

로 설정.-Step 3-1: When the PDSCH allocated by the PDCCH corresponding to the PDCCH monitoring timing m exists in the serving cell c,

It is increased by one for less than or equal to j and the V _temp V _temp

Set to. Also,

If is an empty set, V _temp2

Set to

If is not an empty set, V _temp2

Set to.

- Step 3-2: PDSCH allocated by the PDCCH corresponding to the PDCCH monitoring timing m exists in the serving cell c, and the UE does not receive HARQ-ACK bundling for the codeword through higher layer signaling, and serves at least one When instructed to receive up to two codewords through one PDSCH in at least one downlink BWP of the cell, j is increased by 1 and a HARQ-ACK feedback bit for each codeword is configured.

- Step 3-3: PDSCH allocated by the PDCCH corresponding to the PDCCH monitoring timing m exists in the serving cell c, the UE receives HARQ-ACK bundling for the codeword through higher layer signaling, and at least one serving cell When instructed to receive up to two codewords through one PDSCH in at least one downlink BWP of, HARQ-ACK feedback bits for each codeword are configured as one HARQ-ACK feedback bit through a binary AND operation. .

- Step 3-4: If the PDSCH allocated by the PDCCH corresponding to the PDCCH monitoring timing m exists in the serving cell c, and is not instructed to receive up to two codewords through one PDSCH, for one codeword Configure the HARQ-ACK feedback bit.

- Step 4: Start over from Step 2 by increasing c by 1.

- Step 5: Start over from Step 2 by increasing m by 1.

_-Step 6: If V temp2 is _{less than V temp} , increase j by 1.

로 설정.-Step 7-1: The UE does not receive HARQ-ACK bundling for codewords through higher layer signaling, and receives up to two codewords through one PDSCH in at least one downlink BWP of at least one serving cell When instructed to do so, the total number of HARQ-ACK feedback bits

Set to.

로 설정.-Step 7-2: When the UE is instructed to bundle HARQ-ACK for codewords through higher layer signaling or is not instructed to receive up to two codewords through one PDSCH, full HARQ-ACK feedback Number of bits

Set to.

- Step 8: For HARQ-ACK feedback bits not set in Step 3-1, Step 3-2, Step 3-3, Step 3-4, the HARQ-ACK feedback bit is determined as NACK.

[end of pseudo-code 3]

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

Referring to FIG. 11, radio protocols of the next-generation mobile communication system include NR SDAP (Service Data Adaptation Protocol S25, S70), NR PDCP (Packet Data Convergence Protocol S30, S65), and NR RLC (Radio Link Control) in a terminal and an NR base station, respectively. S35, S60), 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

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

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

- A function of mapping a relective QoS flow to a data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

For the SDAP layer device, the UE may be configured with an 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, bearer or logical channel, and the SDAP header. If is set, the UE uses the NAS QoS reflective configuration 1-bit indicator (NAS reflective QoS) in the SDAP header and the AS QoS reflective configuration 1-bit indicator (AS reflective QoS) to map the QoS flow and data bearer of the uplink and downlink. 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, scheduling information, etc. to support smooth service.

The main functions of the NR PDCP (10-30, 10-65) 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 rearranging the PDCP PDUs received from the lower layer in order based on the PDCP sequence number (SN), and the function of delivering data to the upper layer in the rearranged order. It may include, or may include a function of immediately delivering without considering the order, may include a function of recording lost PDCP PDUs by rearranging the order, and reporting the status of lost PDCP PDUs It may include a function of performing the transmission side, and may include a function of requesting retransmission of lost PDCP PDUs.

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

- Data transfer function (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

- Protocol error detection

- RLC SDU discard function (RLC SDU discard)

- RLC re-establishment

In the above, the in-sequence delivery function of the NR RLC device refers to the function of delivering RLC SDUs received from the lower layer to the upper layer in order, and originally, one RLC SDU is divided into several RLC SDUs and received. If so, it may include a function of reassembling and delivering it, and may include a function of rearranging the received RLC PDUs based on RLC sequence number (SN) or PDCP sequence number (SN), and rearranging the order It may include a function of recording lost RLC PDUs, may include a function of reporting a status of lost RLC PDUs to a transmitting side, and a function of requesting retransmission of lost RLC PDUs. If there is a lost RLC SDU, it may include a function of transferring only RLC SDUs before the lost RLC SDU to a higher layer in order, or if a predetermined timer expires even if there is a lost RLC SDU, the timer It may include a function of delivering all RLC SDUs received before the start of the system in order to the upper layer, or if a predetermined timer expires even if there is a lost RLC SDU, all RLC SDUs received so far are sequentially transferred to the upper layer. It may include the ability to deliver. In addition, RLC PDUs may be processed in the order in which they are received (regardless of the order of serial number and sequence number, in the order of arrival) and delivered to the PDCP device regardless of the order (Out-of sequence delivery). Segments stored in a buffer or to be received in the future may be received, reconstructed into one complete RLC PDU, processed, and delivered 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 may be 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 directly delivering RLC SDUs received from the lower layer to the upper layer regardless of the order, and originally, one RLC SDU is When it is divided into SDUs and received, it may include a function of reassembling and transmitting them, and includes a function of storing the RLC SN or PDCP SN of the received RLC PDUs, sorting the order, and recording the lost RLC PDUs. I 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 and demultiplexing function (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

The NR PHY layer (S45, S50) performs channel coding and modulation of upper layer data, making it into an OFDM symbol and transmitting it through a radio channel, or demodulating and channel decoding an OFDM symbol received through a radio channel and transmitting it to the upper 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 the base station transmits data to the 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 like S10, but a protocol for multiplexing the PHY layer through the MAC layer. You will use the structure. As another example, when a base station transmits data to a terminal based on DC (dual connectivity) using multiple carriers in multiple TRP, the base station and the terminal have a single structure up to the RLC as in S20, but the PHY layer is provided through the MAC layer. It uses a multiplexing protocol structure.

Referring to the above descriptions related to PUCCH, in the current Rel-15 NR, PDSCH transmission from a single cell/transmission point/panel/beam (hereinafter referred to as a transmission reception point (TRP)), or coherent for multiple TRPs ( It is concentrated on PDSCH transmission of the coherent) scheme, and as an optimized HARQ-ACK transmission scheme, a maximum of one PUCCH resource for HARQ-ACK is transmitted within one slot.

Meanwhile, NR release 16 supports non-coherent transmission, that is, non-coherent joint transmission (NC-JT) for each TRP, and at this time, each TRP participating in NC-JT is a separate PDSCH at the same time. Can be transmitted to the terminal. HARQ-ACK information for the PDSCHs may be transmitted through one PUCCH resource, and in consideration of a case where overhead due to information exchange between TRPs is burdened, such as a case where the backhaul delay time per TRP is long A method of transmitting the HARQ-ACK information through separate PUCCH resources for each TRP is also possible. In particular, when HARQ-ACK information (or UCI information) is transmitted through a separate PUCCH resource for HARQ-ACK transmission for each TRP, the HARQ-ACK information may be TDM and transmitted within a slot. The treatment method for the case where the overlap between resources occurs is not defined in Rel-15. In the present invention, by providing a processing method for the above-described case, loss of uplink control information and transmission delay time during NC-JT transmission can be minimized. Meanwhile, the present invention is applicable regardless of whether NC-JT is transmitted if a number of PUCCH resources for HARQ-ACK transmission are included in one slot.

Hereinafter, embodiments of the present disclosure will be described in detail together with the accompanying drawings. 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, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present disclosure and may vary according to the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, the base station may be at least one of a gNode B, gNB, eNode B, Node B, BS (Base Station), a radio access unit, a base station controller, or a node on a network as a subject performing resource allocation of the terminal. 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 a communication function. In addition, an embodiment of the present disclosure will be described below using an NR or LTE/LTE-A system as an example, but an embodiment of the present disclosure may be applied to other communication systems having a similar technical background or channel type. In addition, the embodiments of the present disclosure may be applied to other communication systems through some modifications without significantly departing from the scope of the present disclosure, as determined by a person having skilled technical knowledge.

The contents of the present disclosure are applicable to FDD and TDD systems.

Hereinafter, in the present disclosure, higher signaling is a method of transmitting a signal from the base station to the base station using the downlink data channel of the physical layer or from the terminal to the base station using the uplink data channel of the physical layer, RRC signaling, or PDCP signaling. , Or a medium access control (MAC) control element (MAC control element; MAC CE).

Hereinafter, in the present disclosure, in determining whether to apply cooperative communication, the UE has a specific format in which the PDCCH(s) for allocating the PDSCH to which the cooperative communication is applied, or the PDCCH(s) for allocating the PDSCH to which the cooperative communication is applied. It includes a specific indicator indicating whether or not communication is applied, or the PDCCH(s) allocating a PDSCH to which cooperative communication is applied are scrambled with a specific RNTI, or assuming the application of cooperative communication in a specific section indicated by a higher layer, etc. It is possible to use various methods. For the convenience of explanation later, it will be referred to as the NC-JT case that the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to those described above.

Hereinafter, in the present disclosure, determining the priority between A and B means selecting the one having a higher priority according to a predetermined priority rule and performing the corresponding operation or having a lower priority. It can be mentioned in various ways, such as omitting or dropping the operation for.

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

<First Example: DCI reception for NC-JT>

Unlike the conventional 5G wireless communication system, it is possible to support not only a service requiring a high transmission rate, but also a service having a very short transmission delay and a service requiring a high connection density. In a wireless communication network including a plurality of cells, transmission and reception points (TRP), or beams, coordinated transmission between each cell, TRP, or/and beam increases the strength of a signal received by the terminal or each cell, It is one of the element technologies that can satisfy various service requirements by efficiently performing TRP or/and inter-beam interference control.

Joint Transmission (JT) is a representative transmission technology for cooperative communication described above, and supports one terminal through different cells, TRPs or/and beams through the joint transmission technology to increase the strength of the signal received by the terminal. I can. On the other hand, since the characteristics of each cell, TRP or/and the beam and the channel between the terminal may differ greatly, different precoding, MCS, resource allocation, etc. need to be applied to each cell, TRP or/or the link between the beam and the terminal. . In particular, in the case of non-coherent joint transmission (NC-JT, Non-Coherent Joint Transmission) supporting non-coherent precoding between each cell, TRP or/and beam, each cell, TRP or/and It is important to configure individual down link (DL) transmission information for the beams. On the other hand, the setting of individual DL transmission information for each cell, TRP, or/and beam is a major factor that increases the payload required for DL DCI transmission, which is the reception of a physical downlink control channel (PDCCH) that transmits DCI. It can adversely affect performance. Therefore, it is necessary to carefully design a tradeoff between the amount of DCI information and the PDCCH reception performance for JT support.

12 is a diagram illustrating an example of an antenna port configuration and resource allocation for cooperative communication according to some embodiments in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 12, examples of radio resource allocation for each TRP according to a joint transmission (JT) technique and a situation are shown. In FIG. 12, N000 is an example of coherent joint transmission (C-JT) supporting coherent precoding between each cell, TRP or/and beam. In C-JT, single data (PDSCH) is transmitted to the terminal (N015) in TRP A (N005) and TRP B (N010), and joint precoding is performed in multiple TRPs. This means that TRP A (N005) and TRP B (N010) transmit the same DMRS ports (for example, DMRS ports A and B in both TRPs) for the same PDSCH transmission. In this case, the UE may receive one DCI information for receiving one PDSCH demodulated based on the DMRS transmitted through the DMRS ports A and B.

In FIG. 12, N020 is an example of non-coherent joint transmission (NC-JT) supporting non-coherent precoding between each cell, TRP or/and beam. 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 transmits a different PDSCH to improve throughput compared to single cell, TRP, or/and beam transmission, or each cell, TRP, or/and beam repeatedly transmits the same PDSCH to a single cell, TRP Alternatively, it is possible to improve reliability compared to beam transmission.

When the frequency and time resources used by multiple TRPs for PDSCH transmission are all the same (N040), when the frequency and time resources used by multiple TRPs do not overlap at all (N045), and the frequency and time used by multiple TRPs Various radio resource allocation may be considered, such as when some of the resources overlap (N050). In each case of the above-described radio resource allocation, when multiple TRPs repeatedly transmit the same PDSCH to improve reliability, if the receiving terminal does not know whether the corresponding PDSCH is repeatedly transmitted, the corresponding terminal performs the combination of the corresponding PDSCH in the physical layer. Since (combining) cannot be performed, there may be limitations in improving reliability. Therefore, in the present disclosure, a method for instructing and configuring repetitive transmission for improving NC-JT transmission reliability is provided.

In order to simultaneously allocate a plurality of PDSCHs to one terminal for NC-JT support, DCIs of various types, structures, and relationships may be considered.

13 is a diagram illustrating an example configuration of downlink control information (DCI) for cooperative communication in a wireless communication system according to an embodiment of the present disclosure.

Referring to FIG. 13, four examples of DCI design for NC-JT support are shown.

Referring to FIG. 13, case #1 (N100) is different from each other in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to serving TRP (TRP#0) used when transmitting a single PDSCH. In a situation in which other (N-1) PDSCHs are transmitted, control information for PDSCHs transmitted in (N-1) additional TRPs is in the same form as control information for PDSCHs transmitted in serving TRP (same DCI format). This is an example that is transmitted. That is, all terminals (DCI#0 ~ DCI#(N-1)) different TRPs (TRP#0 ~ TRP#(N-1)) through DCIs having the same DCI format and the same payload. Control information on PDSCHs transmitted in may be obtained.

In the above-described case #1, the degree of freedom for control (allocation) of each PDSCH may be completely guaranteed, but when each DCI is transmitted in a different TRP, a coverage difference for each DCI may occur, resulting in deterioration of reception performance.

Case #2 (N105) is different (N-1) in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in addition to serving TRP (TRP#0) used when transmitting a single PDSCH. In a situation in which two PDSCHs are transmitted, control information for PDSCHs transmitted in (N-1) additional TRPs is transmitted in a different form (different DCI format or different DCI payload) from control information for PDSCHs transmitted in serving TRP. This is an example. For example, in the case of DCI#0, which is control information for the PDSCH transmitted from the serving TRP (TRP#0), all information elements of DCI format 1_0 to DCI format 1_1 are included, but cooperation TRP (TRP#1 In the case of shortened DCI (hereinafter, sDCI) (sDCI#0 to sDCI#(N-2)), which is control information for PDSCHs transmitted from ~TRP#(N-1)), information of DCI format 1_0 to DCI format 1_1 May contain only some of the elements. Therefore, in the case of sDCI that transmits control information for PDSCHs transmitted in the cooperative TRP, the payload is small compared to normal DCI (nDCI) that transmits PDSCH-related control information transmitted in the serving TRP, or less than nDCI. It is possible to include reserved bits as many as the number of bits.

In case #2 described above, the degree of freedom for controlling (allocation) of each PDSCH may be limited according to the contents of the information element included in sDCI, but since the reception performance of sDCI is superior to nDCI, the coverage difference per DCI It may be less likely to occur.

Case #3 (N110) is different (N-1) in (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than serving TRP (TRP#0) used when transmitting a single PDSCH In a situation in which two PDSCHs are transmitted, control information for PDSCHs transmitted in (N-1) additional TRPs is transmitted in a different form (different DCI format or different DCI payload) from control information for PDSCHs transmitted in serving TRP. This is an example. For example, in the case of DCI#0, which is control information for the PDSCH transmitted from the serving TRP (TRP#0), all information elements of DCI format 1_0 to DCI format 1_1 are included, and cooperation TRP (TRP#1 In the case of control information for PDSCHs transmitted in ~TRP#(N-1)), it is possible to collect and transmit only some of the information elements of DCI format 1_0 to DCI format 1_1 in one'secondary' DCI (sDCI). 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, in the case of information not included in the sDCI such as a bandwidth part (BWP) indicator or a carrier indicator, DCI (DCI#0, normal DCI, nDCI) of the serving TRP may be followed.

In case #3, the degree of freedom for controlling (allocation) of each PDSCH may be limited according to the contents of the information element included in the sDCI, but the reception performance of sDCI can be adjusted and compared with case #1 or case #2, The complexity of DCI blind decoding may be reduced.

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

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 the cooperative TRP, and has special restrictions. If not specified, the description is similarly applicable to the various auxiliary DCIs.

In the following description and embodiments, the above-described case #1, case #2, and case #3 in which more than one DCI (PDCCH) is used to support NC-JT are classified into multiple PDCCH-based NC-JTs, and NC- Case #4, in which a single DCI (PDCCH) is used for JT support, can be classified as a single PDCCH-based NC-JT.

In embodiments of the present disclosure, "cooperation TRP" may be replaced with various terms such as "cooperation panel" or "cooperation beam" when applied in practice.

In the embodiments of the present disclosure, "when NC-JT is applied" means "when a terminal receives one or more PDSCHs at the same time in one BWP", "when a terminal simultaneously receives two or more TCIs (Transmission Configuration) in one BWP. Indicator) In the case of receiving the PDSCH based on the indication", "when the PDSCH received by the terminal is associated with one or more DMRS port groups", it is possible to be variously interpreted according to the situation, but one for convenience of explanation Used as an expression.

In the present invention, a radio protocol structure for NC-JT can be used in various ways according to a TRP deployment scenario. For example, when there is no or small backhaul delay between cooperative TRPs, it is possible to use a structure based on MAC layer multiplexing similar to S10 of FIG. 11 (CA-like method). On the other hand, when the backhaul delay between cooperative TRPs is so large that it cannot be ignored (e.g., when a time of 2 ms or more is required for information exchange such as CSI, scheduling, HARQ-ACK, etc. between cooperative TRPs) By using an independent structure for each TRP, it is possible to secure characteristics that are robust to delay (DC-like method).

<Embodiment 1-1: Method for Setting Downlink Control Channel for Multi-PDCCH-Based NC-JT Transmission>

In the multiple PDCCH-based NC-JT, when DCI is transmitted for the PDSCH schedule of each TRP, it may have a CORESET or search space that is classified for each TRP. CORESET or search space for each TRP can be set as at least one of the following cases.

● Higher layer index setting for each CORESET: A higher layer index value for each CORESET that has been set, and the TRP that transmits the PDCCH from the corresponding CORESET can be identified. That is, in the set of CORESETs having the same upper layer index value, it may be considered that the same TRP transmits the PDCCH or that the PDCCH scheduling the PDSCH of the same TRP is transmitted.

● Multiple PDCCH-Config configuration: Multiple PDCCH-Configs are configured in one BWP, and each PDCCH-Config can be viewed as configuring a PDCCH configuration for each TRP. Here, a list of CORESET for each TRP and/or a list of search spaces for each TRP may be configured.

● CORESET beam/beam group configuration: TRP corresponding to the corresponding CORESET can be classified through a beam or beam group set for each CORESET. For example, when the same TCI state is set for a plurality of CORESETs, the corresponding CORESETs may be considered to be transmitted through the same TRP, or a PDCCH scheduling a PDSCH of the same TRP may be considered to be 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, a TRP for each search space can be classified. 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 that the PDCCH scheduling the PDSCH of the same TRP is transmitted in the corresponding search space. have.

By dividing the CORESET or search space for each TRP as described above, it is possible to classify PDSCH and HARQ-ACK information for each TRP, and through this, it is possible to generate an independent HARQ-ACK codebook for each TRP and use an independent PUCCH resource.

<Second embodiment: method of transmitting HARQ-ACK information for NC-JT transmission>

The following embodiment provides a detailed method of transmitting HARQ-ACK information for NC-JT transmission.

14A, 14B, 14C, and 14D illustrate various DCI configurations for NC-JT transmission and a method of transmitting HARQ-ACK information according to a PUCCH configuration.

값을 통해 지시될 수 있다.First, FIG. 14a (option #1: HARQ-ACK for single-PDCCH NC-JT) (14-00) shows that in the case of single-PDCCH-based NC-JT, one or more PDSCHs 14-05 scheduled by TRP It shows a situation in which HARQ-ACK information for is transmitted through one PUCCH resource (14-10). The PUCCH resource is the PRI value in the DCI and

Can be indicated by value.

14B (Option #2) to 14D (option #4) (14-20, 14-40, 14-60)) illustrate the case of multi-PDCCH-based NC-JT. At this time, each option may be classified according to the number of PUCCH resources to transmit HARQ-ACK information corresponding to the PDSCH of each TRP and the position of the PUCCH resource on the time axis.

14B (Option #2: joint HARQ-ACK) (14-20) shows a situation in which HARQ-ACK information corresponding to the PDSCHs 14-25 and 14-26 of each TRP is transmitted through one PUCCH resource. do. All HARQ-ACK information for each TRP may be generated based on a single HARQ-ACK codebook, or HARQ-ACK information for each TRP may be generated based on a separate HARQ-ACK codebook.

When an individual HARQ-ACK codebook for each TRP is used, the TRP is a set of CORESETs having the same upper layer index, the same TCI state or a set of CORESETs belonging to the beam or beam group, as defined in Example 1-1, and the same TCI state. Alternatively, it may be classified as at least one of a beam or a set of search spaces belonging to a beam group.

값에 의해 결정될 수 있다. 만일 다수의 PDCCH가 지시하는

값이 동일 슬롯을 가리키는 경우, 해당 PDCCH들은 모두 동일 TRP에서 스케줄했다고 간주하고 이들에 대응하는 HARQ-ACK 정보를 모두 전송할 수 있다.14c (Option #3: inter-slot TDMed separate HARQ-ACK) 14-40 shows HARQ-ACK information corresponding to the PDSCHs 14-45 and 14-46 of each TRP in different slots 14-52 , 14-53) shows a situation of transmitting through the PUCCH resource (14-50, 14-51). The slot in which the PUCCH resource per TRP is transmitted is described above

Can be determined by value. If multiple PDCCHs indicate

When the value indicates the same slot, all corresponding PDCCHs are considered to be scheduled in the same TRP, and all HARQ-ACK information corresponding to them can be transmitted.

값에 의해 결정될 수 있으며, 만일 다수의 PDCCH가 지시하는

값이 동일 슬롯을 가리키는 경우 적어도 다음 중 하나의 방법을 통해 PUCCH resource 선택 및 전송 심볼을 결정할 수 있다.14D (Option #4: intra-slot TDMed separate HARQ-ACK) 14-60 shows HARQ-ACK information corresponding to the PDSCHs 14-65 and 14-66 of each TRP in the same slot 14-75. It shows a situation in which different symbols are transmitted through different PUCH resources (14-70, 14-71). The slot in which the PUCCH resource per TRP is transmitted is described above

It can be determined by a value, and if multiple PDCCHs indicate

When the value indicates the same slot, PUCCH resource selection and transmission symbol may be determined through at least one of the following methods.

● PUCCH resource group setting by TRP

A PUCCH resource group for HARQ-ACK transmission per TRP can be configured. When the TRP for each CORESET / search space is classified as in Example 1-1, the PUCCH resource for HARQ-ACK transmission for each TRP may be selected within the PUCCH resource group for the corresponding TRP. TDM may be expected between PUCCH resources selected from different PUCCH resource groups, that is, it may be expected that the selected PUCCH resources do not overlap in symbol units. As described above, an individual HARQ-ACK codebook for each TRP may be generated in the PUCCH resource selected for each TRP and then transmitted.

● Different PRI instructions for each TRP

When the TRP for each CORESET / search space is classified as in Example 1-1, PUCCH resources for each TRP may be selected according to the PRI. That is, the PUCCH resource selection process in Rel-15 described above may be independently performed for each TRP. At this time, the PRIs used to determine the PUCCH resource for each TRP must be different. For example, the UE may not expect that the PRI used to determine the PUCCH resource for each TRP is indicated with the same value. In addition, TDM can be expected between the PUCCH resource corresponding to the PRI for each TRP. That is, it can be expected that the selected PUCCH resources do not overlap on a symbol basis. As described above, an individual HARQ-ACK codebook for each TRP may be generated in the PUCCH resource selected for each TRP and then transmitted.

값을 서브슬롯 단위로 정의●

Define values in units of subslots

값을 서브슬롯 단위로 정의할 수 있다. 예컨대 동일 서브슬롯에 HARQ-ACK을 보고하도록 지시된 PDSCH/PDCCH들에 대한 HARQ-ACK codebook을 생성 후 PRI로 지시된 PUCCH resource에 전송할 수 있다. 상기 HARQ-ACK codebook 생성 및 PUCCH resource 선택 과정은 CORESET / 탐색공간 별 TRP 구분 여부와 관계 없을 수 있다.Follow the PUCCH resource selection process in Rel-15 described above,

Value can be defined in units of subslots. For example, after generating a HARQ-ACK codebook for PDSCH/PDCCHs instructed to report HARQ-ACK in the same subslot, it may be transmitted to a PUCCH resource indicated by the PRI. The process of generating the HARQ-ACK codebook and selecting a PUCCH resource may be irrelevant to whether the CORESET / TRP for each search space is classified.

When the terminal supports NC-JT reception, one of the options may be set through an upper layer or may be implicitly selected according to a situation. For example, in a UE supporting multi-PDCCH-based NC-JT, one of option 2 and option 3/4 may be selected as an upper layer. As another example, depending on whether the single-PDCCH-based NC-JT or multi-PDCCH-based NC-JT is supported/configured, one of option 1 for the former and option 2/3/4 for the latter may be selected. As another example, in the multi-PDCCH-based NC-JT, the option used according to the selection of the PUCCH resource may be determined. When PUCCH resources of the same slot are selected in different TRPs, if the corresponding PUCCH resources are different and do not overlap in symbol units, HARQ-ACK is transmitted according to option 4, and if the PUCCH resources overlap in symbol units or are identical, HARQ according to option 2 -ACK can be transmitted. When PUCCH resources of different slots are selected in different TRPs, HARQ-ACK may be transmitted according to option 3. The setting for the option may be dependent on the terminal capability. For example, the base station may receive the capability of the terminal according to the above-described procedure, and may set the option based on this. For example, option 4 configuration is allowed only for a terminal having the capability to support intra-slot TDMed separate HARQ-ACK, and a terminal not equipped with the corresponding capability may not expect configuration according to option 4.

<Third Example; PUCCH-PUCCH overlap processing method for multi-PDCCH-based NC-JT>

In the multi-PDCCH-based NC-JT, when the intra-slot TDMed separate HARQ-ACK is used, multiple HARQ-ACKs in one slot may be transmitted through a PUCCH resource. This is differentiated from Rel-15, in which only one HARQ-ACK is transmitted within one slot. Therefore, a specific processing method for a case where an overlap between the PUCCH resource for the HARQ-ACK and the PUCCH resource for other uplink control information occurs is presented in this embodiment.

In this embodiment, a method for the case of occurrence of overlap between PUCCH resources in which multi-repetition is not set will be described first. At this time, the following two cases shown in FIG. 15 will be described.

15A is a diagram illustrating a case in which overlap occurs between PUCCH resources according to an embodiment of the present disclosure.

Referring to Figure 15, Case 1 (15-10) is the overlap between PUCCH resource #1, #2 (15-11, 15-12) and other PUCCH resource #3 (15-13) for HARQ-ACK transmission It indicates the case of occurrence.

Case 2 (15-20) represents a case where an overlap occurs between PUCCH resource #1 (15-21) and other PUCCH resource (15-23) #3 for HARQ-ACK transmission.

Some of the above cases may not occur according to the PUCCH resource configuration for each TRP and the HARQ-ACK transmission method described in Embodiment 2.

For example, only Case 2 may occur in a situation in which joint HARQ-ACK or inter-slot TDMed separate HARQ-ACK is applied.

On the other hand, in a situation where intra-slot TDMed separate HARQ-ACK is applied, both Case 1 and Case 2 may occur.

As another example, some of the above cases may not occur depending on whether or not a PUCCH resource group for each TRP described in Embodiment 2 is set. If all PUCCH resources are classified according to the PUCCH resource group for each TRP, only Case 2 may occur. On the other hand, in a situation in which a PUCCH resource group for each TRP is not configured or only PUCCH resources for HARQ-ACK transmission are classified according to a PUCCH resource group for each TRP, both Case 1 and Case 2 may occur.

It will be described in Figure 15b how to process PUCCH according to the overlap of the PUCCH resource according to the Figure 15a.

15B is a diagram illustrating a method of transmitting a PUCCH when an overlap occurs between PUCCH resources according to an embodiment of the present disclosure.

Referring to FIG. 15B, the UE may receive configuration information related to a PUCCH resource in step 1530. The configuration information may be received through higher layer signaling.

In this case, the setting information may include one or more PUCCH resource sets as described above, and one or more PUCCH resources may be included in one PUCCH resource set. For details, refer to the above.

In addition, the terminal may receive the DCI including resource allocation information in step 1540. The resource allocation information may include at least one of information such as information on a resource for receiving downlink data and information on a resource for transmitting uplink control information.

In this case, the information on the resource for transmitting the uplink control information may include an indicator indicating the PUCCH resource received through the configuration information. In addition, it may include information K1 on the slot location for transmitting the PUCCH resource. For details, refer to the above.

In addition, when the terminal supports NC-JT reception, the terminal can receive DCI for each TRP. In this case, various methods proposed in FIG. 13 may be used as a method of receiving DCI, and for details, refer to the foregoing.

In addition, the UE may check a PUCCH resource to transmit uplink control information in step 1550. The terminal may check the PUCCH resource based on at least one of the configuration information or DCI.

When NC-JT is set in the terminal, the terminal must transmit UCI for a plurality of TRPs, and a plurality of PUCCH resources can be checked. At this time, when a plurality of confirmed PUCCH resources are located in one slot, a PUCCH resource group is set for each TRP as described above, or a different PRI is indicated for each TRP, or the K1 value included in DCI is used in subslot units. It can be defined so that it can be assigned to another symbol within one slot. For details, refer to the above.

Meanwhile, the UE may transmit capability information on whether or not the UE can multiplex and transmit control information for HARQ-ACK transmission through the TDMed PUCCH resource within one slot, and only when the UE has capability, the eNB As described above, a plurality of PUCCH resources for HARQ-ACK transmission can be configured in one slot. Details related to the capability transmission/reception method and transmission/reception timing are the same as described above, and will be omitted below.

In this way, when two or more PUCCH resources (PUCCH #1, PUCCH #2) are located in one slot, a PUCCH resource (PUCCH #3) for another UCI transmission may be allocated to the same slot at the same time. In this case, the other uplink information may include SR, CSI, etc., or may include HARQ-ACK information for other TRP. Meanwhile, for convenience of explanation, PUCCH #1 and PUCCH #2 TDM in the time axis among the PUCCH resources shown in FIG. 15A may be referred to as a first PUCCH, and PUCCH #3 may be referred to as a second PUCCH. Alternatively, PUCCH #1, PUCCH #2, and PUCCH #3 may be referred to as a first PUCCH, a second PUCCH, and a third PUCCH, respectively.

Therefore, the terminal can check whether the overlap occurred between the PUCCH resource in step 1560. At this time, the UE can check whether an overlap has occurred between the PUCCH resource (eg, TDMed PUCCH resource in the slot) and other PUCCH resource identified in step 1550. In this case, the different PUCCH resource may mean different UCI (eg, UCI excluding HARQ-ACK). As described above, the PUCCH resource (PUCCH #1, PUCCH #2) identified in step 1550 may be referred to as a first PUCCH, and another PUCCH resource (PUCCH #3) may be referred to as a second PUCCH.

At this time, the overlap between PUCCH resources may mean the overlap of symbol units. Therefore, step 1560 may mean a step of checking whether there is a PUCCH resource overlapping with the TDM PUCCH resource in the slot as shown in FIG. 15A.

If the result of the check does not overlap, the UE can transmit UCI through each PUCCH resource. For example, when a PUCCH resource corresponding to each of the TRP 1 and TRP2 is included in one slot and an intra-slot TDMed separate HARQ-ACK is set, the UE multiplexes the HARQ-ACK information for each TRP to the PUCCH resource for each TRP. In this case, the PUCCH resource for each TRP may be determined according to the PUCCH resource selection process in the intra-slot TDMed separate HARQ-ACK described above. In addition, the other uplink information may also be transmitted through an allocated PUCCH resource.

On the other hand, when overlap occurs, case 1 and case 2 described in Fig. 15a may occur.

Accordingly, when it is determined that the terminal corresponds to case 1 in step 1570, the terminal may perform an operation according to the case.

Meanwhile, when it is determined that the terminal corresponds to case 2 in step 1580, the terminal may perform an operation according to the case.

Details of the operation according to case 1 and case 2 will be described below.

Returning to the description of Figure 15a, in the case of Case 1, it may be determined whether the Rel-15-based PUCCH overlapping processing method can be applied according to whether SR or CSI is transmitted through PUCCH resource-specific format and PUCCH resource #3. If the SR is transmitted through PUCCH resource #3, the following problems may occur if the Rel-15 based PUCCH multiplexing method is applied.

When one of the PUCCH resources for HARQ-ACK transmission is PUCCH format 1 and the PUCCH resource #3 for SR transmission is PUCCH format 1. Hereinafter, for convenience of technology, a PUCCH resource for HARQ-ACK transmission corresponding to PUCCH format 1 is referred to as PUCCH resource #1.

In the above case, at this time, if the SR is positive, HARQ-ACK for PUCCH resource #1 should be transmitted through PUCCH resource #3. However, since PUCCH resource #3 is not TDM with PUCCH resource #2, it needs to be changed in Rel-15-based processing method.

Therefore, in order to solve the above problem, at least one of the following methods may be considered.

● Method 1-1: When applying intra-slot TDMed separate HARQ-ACK, multiplexing to drop SR when overlapping between PUCCH resource for HARQ-ACK transmission (PUCCH format 1) and PUCCH resource for SR transmission (PUCCH format 1) Rules change.

● Method 1-2: When intra-slot TDMed separate HARQ-ACK is applied, PUCCH format 1 is not set for HARQ-ACK transmission.

● Method 1-3: When applying intra-slot TDMed separate HARQ-ACK, PUCCH format 1 is not set for SR transmission

● Method 1-4: When applying intra-slot TDMed separate HARQ-ACK, the UE does not expect an overlap between the PUCCH resource (PUCCH format 1) for HARQ-ACK transmission and the (PUCCH format 1) for SR transmission.

Meanwhile, the following problems may occur when the Rel-15 based PUCCH multiplexing method is applied. If the PUCCH resource for HARQ-ACK transmission is not PUCCH format 1. In this case, the same SR information is multiplexed and transmitted to both PUCCH resources for HARQ-ACK transmission. This may be an undesirable situation in the network. For example, a plurality of TRPs receiving HARQ-ACK may perform all of the response procedures for the SR request, and unnecessary control information transmission/reception and uplink resource allocation may occur accordingly. Therefore, there is a need for a method of selecting one of PUCCH resource #1, #2, and allowing the SR to be multiplexed only for that resource.

Therefore, in order to solve the above problem, at least one of the following methods may be considered. Specifically, the SR is multiplexed to two PUCCH resources for HARQ-ACK transmission and transmitted, or the SR may be multiplexed to one of two PUCCH resources and transmitted, and a method of selecting one PUCCH resource The following method may be considered.

● Method 2-1: Select by index or order. For example, it is possible to select a PUCCH resource transmitted first on the time axis, a PUCCH resource corresponding to a low PRI, or a PUCCH resource corresponding to a low PUCCH resource group.

● Method 2-2: Selection based on maximum payload. For example, it is possible to preferentially select a PUCCH resource having a large transmittable maximum payload.

● Method 2-3: Selection according to PUCCH format. Long PUCCH with good coverage may be selected prior to short PUCCH. In addition, PUCCH format 2/3/4 capable of transmitting a payload exceeding 2 bits may be selected prior to PUCCH 0/1.

● Method 2-4: Selection according to TRP. When SR information is to be transmitted to a specific TRP, a PUCCH resource corresponding to the same TRP can be selected. For example, it is possible to select a PUCCH resource for HARQ-ACK in which spatial relation info identical to that of PUCCH resource #3 is activated. Alternatively, a PUCCH resource in a PUCCH resource group belonging to the TRP corresponding to the SR may be selected. Or, when the TRP index is set in the CORESET in which the DCI scheduled transmission of the PDSCH and HARQ-ACK PUCCH is transmitted, a corresponding TRP index is set for each SR ID, or the TRP index to transmit all SRs is set to a specific value, such as TRP index 0. Can be assumed. Alternatively, a TRP index may be set on a PUCCH resource to transmit an SR, or a specific value, for example, TRP index 0 may be assumed. At this time, it is possible to select a PUCCH resource corresponding to the HARQ-ACK having the same value as the above-described SR ID or TRP index associated with the PUCCH for SR transmission. Alternatively, the TRP index may be expressed as a parameter set for PUCCH power control. For example, the TRP index may be expressed as one of the following values or a combination thereof in the following PUCCH-PowerControl IE set as RRC.

In more detail, the TRP index may correspond to the p0-PUCCH-Id value set for PUCCH power control. For example, when p0-PUCCH-Id has a value between 1 and 4, it may correspond to TRP index 0, and when p0-PUCCH-Id has a value between 5 and 8, it may correspond to TRP index 1. The mapping between the range of the p0-PUCCH-Id and the TRP index may be changed. Alternatively, the TRP index may correspond to a pathlossReferenceRS configured for PUCCH power control. Alternatively, the TRP index may correspond to a power control adjustment state index set for PUCCH power control. The power control adjustment state index is an indicator indicating the power control state of the PUCCH resource, and may also be referred to as an expression such as a closed loop power control index and a TRP/panel specific closed loop power control index. When the twoPUCCH-PC-AdjustmentStates value of the RRC parameter is set to twoStates, the power control adjustment state index may have one of two values, e.g., a value expressed as i0 or i1, where i0 is TRP index 0, i1 May correspond to TRP index 1. The i0 or i1 mentioned above may be indicated in the form of a closedLoopIndex parameter value in spatial relation info activated for each PUCCH/PUCCH group as follows.

As described above, among PUCCH resources, a resource in which the closedLoopIndex parameter connected to spatial relation info is set to i0 is a PUCCH resource corresponding to TRP index 0, and a resource in which the closedLoopIndex parameter is set to i1 can be viewed as a PUCCH resource corresponding to TRP index 1. have.

On the other hand, the power control adjustment state index can be extended so that two can be set per TRP. Therefore, if the number of TRPs is supported up to 2, the total configurable power control adjustment state index can be extended to be set up to 4. For example, FourStates may be set as the value of the twoPUCCH-PC-AdjustmentStates parameter, or a new parameter such as the fourPUCCH-PC-AdjustmentStates parameter may be set. At this time, if the closedLoopIndex parameter connected to the spatial relation info is set to i0, i1, TRP index 0, the closedLoopIndex parameter is set to i2, i3, or a new parameter in the spatial relation info, for example, closedLoopIndexNew parameter, is additionally set. It can be seen as 1. In addition, as described above, a connection relationship between the PUCCH resource and the TRP index can be established.

If the PUCCH resource for the TRP to which the SR is to be transmitted is not selected (eg, due to the absence of information such as spatial relation info), the UE may not multiplex the SR and HARQ-ACK. In this case, a PUCCH resource or UCI having a lower priority may be dropped according to the priority in the order of HARQ-ACK> SR> CSI.

Alternatively, for simplification of the terminal operation, the base station may properly schedule a PUCCH resource or instruct multiplexing configuration so that the above-described case does not occur.

Next, in case of Case 1, if CSI is transmitted through PUCCH resource #3, it may be determined whether to multiplex HARQ-ACK and CSI by higher layer configuration. If the multiplexing is configured, the following problems may occur when applying the Rel-15 based PUCCH multiplexing method.

The same CSI information may be multiplexed and transmitted to both PUCCH resources for HARQ-ACK transmission, which may lead to waste of uplink transmission resources and transmission power due to redundant CSI payload transmission. Therefore, there is a need for a method of selecting one of PUCCH resource #1, #2, and allowing CSI to be multiplexed only for that resource.

In order to solve the above problem, at least one of the following methods may be considered.

● Method 3-1: Select by index or order. For example, it is possible to select a PUCCH resource transmitted first on the time axis, a PUCCH resource corresponding to a low PRI, or a PUCCH resource corresponding to a low PUCCH resource group.

● Method 3-2: Selection based on maximum payload. A PUCCH resource having a large maximum payload that can be transmitted may be prioritized and selected.

● Method 3-3: Selection according to PUCCH format. Long PUCCH with good coverage may be selected prior to short PUCCH. In addition, when subband CSI is reported, PUCCH format 3/4 capable of subband CSI transmission may be selected prior to PUCCH format 2 capable of only wideband CSI transmission.

● Method 3-4: Selection according to TRP. When only the channel state for a specific TRP is included in the CSI information, it may be desirable to multiplex the CSI information only on the PUCCH resource to be transmitted to the corresponding TRP. To this end, for example, a PUCCH resource for HARQ-ACK in which spatial relation info identical to that of PUCCH resource #3 is activated may be selected. Alternatively, a PUCCH resource in the PUCCH resource group belonging to the TRP corresponding to the CSI information may be selected. Alternatively, when the TRP index is set in the CORESET in which the DCI scheduled transmission of the PDSCH and HARQ-ACK PUCCH is transmitted, the TRP index may be set in the CSI report/resource setting or the TRP index may be set in the PUCCH resource for CSI report transmission. At this time, it is possible to select a PUCCH resource corresponding to the HARQ-ACK having the same value as the TRP index associated with the CSI PUCCH described above. If the PUCCH resource for the TRP to which CSI is to be transmitted is not selected, the UE may not multiplex the CSI with other UCI. In this case, a PUCCH resource or UCI having a lower priority may be dropped according to the priority in the order of HARQ-ACK> SR> CSI. When multiple CSIs are overlapped, the priority between CSIs may be applied. Or, when the TRP index is set in the CSI report/resource setting or the TRP index is set in the PUCCH resource for CSI report transmission, a situation in which multiple CSIs having different TRP indexes are overlapped may occur. In this case, when the corresponding CSIs are configured to be multiplexed, for example, when the above-described multi-CSI-PUCCH-ResourceList is set, the TRP index of the PUCCH resource to transmit the multiplexed CSI may be unclear. The above situation can be prevented by properly scheduling PUCCH resources for CSI report transmission in the network. Alternatively, when CSI reports/resources with different TRP indexes are set or activated/triggered, multi-CSI-PUCCH-ResourceList may not be expected to be set. Alternatively, a TRP index may be set for each PUCCH resource corresponding to the multi-CSI-PUCCH-ResourceList, or a specific TRP index value, for example, TRP index 0 may be assumed. Alternatively, in this case, even if multi-CSI-PUCCH-ResourceList is set, multiplexing between overlapping CSI reports is not performed, and dropping according to priority may be performed. The priority at this time may follow the Rel-15-based CSI report priority described above.

Alternatively, the TRP index may be expressed as a parameter set for PUCCH power control. For example, the TRP index may be expressed as one of the following values or a combination thereof in the following PUCCH-PowerControl IE set as RRC.

In more detail, the TRP index may correspond to the p0-PUCCH-Id value set for PUCCH power control. For example, when p0-PUCCH-Id has a value between 1 and 4, it may correspond to TRP index 0, and when p0-PUCCH-Id has a value between 5 and 8, it may correspond to TRP index 1. The mapping between the range of the p0-PUCCH-Id and the TRP index may be changed. Alternatively, the TRP index may correspond to a pathlossReferenceRS configured for PUCCH power control. Alternatively, the TRP index may correspond to a power control adjustment state index set for PUCCH power control. The power control adjustment state index is an indicator indicating the power control state of the PUCCH resource, and may also be referred to as an expression such as a closed loop power control index and a TRP/panel specific closed loop power control index. When the twoPUCCH-PC-AdjustmentStates value of the RRC parameter is set to twoStates, the power control adjustment state index may have one of two values, e.g., a value expressed as i0 or i1, where i0 is TRP index 0, i1 May correspond to TRP index 1. The i0 or i1 mentioned above may be indicated in the form of a closedLoopIndex parameter value in spatial relation info activated for each PUCCH/PUCCH group as follows.

As described above, among PUCCH resources, a resource in which the closedLoopIndex parameter connected to spatial relation info is set to i0 is a PUCCH resource corresponding to TRP index 0, and a resource in which the closedLoopIndex parameter is set to i1 can be viewed as a PUCCH resource corresponding to TRP index 1. have.

On the other hand, the power control adjustment state index can be extended so that two can be set per TRP. Therefore, if the number of TRPs is supported up to 2, the total configurable power control adjustment state index can be extended to be set up to 4. For example, FourStates may be set as the value of the twoPUCCH-PC-AdjustmentStates parameter, or a new parameter such as the fourPUCCH-PC-AdjustmentStates parameter may be set. At this time, if the closedLoopIndex parameter connected to the spatial relation info is set to i0, i1, TRP index 0, the closedLoopIndex parameter is set to i2, i3, or a new parameter in the spatial relation info, for example, closedLoopIndexNew parameter, is additionally set. It can be seen as 1. In addition, as described above, a connection relationship between the PUCCH resource and the TRP index can be established.

However, when CSI is transmitted through PUCCH resource #3, and multiplexing between HARQ-QCK and CSI is configured, a method of multiplexing and transmitting the same CSI information to both PUCCH resources may be used.

Alternatively, for simplification of the terminal operation, the base station may properly schedule a PUCCH resource or instruct multiplexing configuration so that the above-described case does not occur. For example, when the above-described simultaneousHARQ-ACK-CSI is configured, the UE may not expect a situation in which CSI is transmitted through PUCCH resource #3 in Case 1.

For Case 2, beams between overlapped PUCCH resources may be different. This can be interpreted that the TRP to be transmitted through the overlapped PUCCH resource may be different. If multiplexing between corresponding PUCCH resources is configured, some of the multiplexed UCIs may be transmitted to an untargeted TRP. At least one of the following methods may be considered to solve this problem.

● Method 4-1: A beam applied to a PUCCH corresponding to a UCI having a high priority among multiplexed UCIs is followed. Through this, UCI with at least a high priority can be transmitted to a target TRP. The UCI priority may be HARQ-ACK> SR> CSI. When multiple CSIs are overlapped, the priority between CSIs may be applied.

● Method 4-2: If the beams between overlapped PUCCHs are different, multiplexing may not be performed, which may take precedence over higher layer settings. Accordingly, only one of the overlapped PUCCHs is selected and transmitted, and the rest may be dropped, and the PUCCH selection may follow the priority between UCIs contained in the overlapped PUCCH. The UCI priority may be HARQ-ACK> SR> CSI. When multiple CSIs are overlapped, inter-CSI priority may be applied. The above-described PUCCH beam may be indicated through PUCCH spatial relation info. Alternatively, the above-described PUCCH beam may be replaced with a TRP for transmitting PUCCH, and in this case, the TRP may be expressed as PUCCH spatial relation info, PUCCH resource group, TRP index, and the like. For example, when the TRP index is set in the CORESET in which the DCI scheduled for PDSCH and HARQ-ACK PUCCH transmission is transmitted, the TRP index can be set in the CSI report/resource setting, or the TRP index can be set in the PUCCH resource for CSI report transmission. . In this case, a PUCCH resource corresponding to the CSI having the same value as the TRP index associated with the HARQ-ACK PUCCH described above may be selected.

Alternatively, the TRP index, which may be set in a PUCCH resource for CSI report or SR or HARQ-ACK transmission, may be expressed as a parameter set for PUCCH power control. For example, the TRP index may be expressed as one of the following values or a combination thereof in the following PUCCH-PowerControl IE set as RRC.

In more detail, the TRP index may correspond to the p0-PUCCH-Id value set for PUCCH power control. For example, when p0-PUCCH-Id has a value between 1 and 4, it may correspond to TRP index 0, and when p0-PUCCH-Id has a value between 5 and 8, it may correspond to TRP index 1. The mapping between the range of the p0-PUCCH-Id and the TRP index may be changed. Alternatively, the TRP index may correspond to a pathlossReferenceRS configured for PUCCH power control. Alternatively, the TRP index may correspond to a power control adjustment state index set for PUCCH power control. The power control adjustment state index is an indicator indicating the power control state of the PUCCH resource, and may also be referred to as an expression such as a closed loop power control index and a TRP/panel specific closed loop power control index. When the twoPUCCH-PC-AdjustmentStates value of the RRC parameter is set to twoStates, the power control adjustment state index may have one of two values, e.g., a value expressed as i0 or i1, where i0 is TRP index 0, i1 May correspond to TRP index 1. The i0 or i1 mentioned above may be indicated in the form of a closedLoopIndex parameter value in spatial relation info activated for each PUCCH/PUCCH group as follows.

As described above, among PUCCH resources, a resource in which the closedLoopIndex parameter connected to spatial relation info is set to i0 is a PUCCH resource corresponding to TRP index 0, and a resource in which the closedLoopIndex parameter is set to i1 can be viewed as a PUCCH resource corresponding to TRP index 1. have.

On the other hand, the power control adjustment state index can be extended so that two can be set per TRP. Therefore, if the number of TRPs is supported up to 2, the total configurable power control adjustment state index can be extended to be set up to 4. For example, FourStates may be set as the value of the twoPUCCH-PC-AdjustmentStates parameter, or a new parameter such as the fourPUCCH-PC-AdjustmentStates parameter may be set. At this time, if the closedLoopIndex parameter connected to the spatial relation info is set to i0, i1, TRP index 0, the closedLoopIndex parameter is set to i2, i3, or a new parameter in the spatial relation info, for example, closedLoopIndexNew parameter, is additionally set. It can be seen as 1. In addition, as described above, a connection relationship between the PUCCH resource and the TRP index can be established.

If the TRP index is set in the CSI report/resource setting or the TRP index is set in the PUCCH resource for CSI report transmission, a situation in which a plurality of CSIs with different TRP indexes overlap may occur. At this time, when the corresponding CSIs are configured to be multiplexed, for example, when the above-described multi-CSI-PUCCH-ResourceList is set, the TRP index of the PUCCH resource to transmit the multiplexed CSI may be unclear. The above situation can be prevented by properly scheduling PUCCH resources for CSI report transmission in the network. Alternatively, when CSI reports/resources with different TRP indexes are set or activated/triggered, multi-CSI-PUCCH-ResourceList may not be expected to be set. Alternatively, a TRP index may be set for each PUCCH resource corresponding to the multi-CSI-PUCCH-ResourceList, or a specific TRP index value, for example, TRP index 0 may be assumed. Alternatively, in this case, even if multi-CSI-PUCCH-ResourceList is set, multiplexing between overlapping CSI reports is not performed, and dropping according to priority may be performed. The priority at this time may follow the Rel-15-based CSI report priority described above.

● Method 4-3: For simplification of terminal operation, the base station can properly schedule the PUCCH resource so that the above-described overlapped PUCCH beam/TRP does not differ from each other.

In this case, the TRP or TRP index may be classified by the method described above in Method 4-2. For example, a TRP index may be set for each PUCCH resource. Meanwhile, the TRP index may not be set in the PUCCH resource for HARQ-ACK transmission, or may not be used even if it is set. Instead, the TRP index set in the CORESET in which the DCI scheduled for the PUCCH transmission is transmitted may be actually used. In addition, the UE may not expect that the TRP index set for each PUCCH resource and the TRP index value set in the CORESET for which the DCI scheduled for PUCCH transmission is transmitted are different from each other.

For example, the TRP index set for each PUCCH resource may be expressed as a parameter set for PUCCH power control. For example, the TRP index may be expressed as one of the following values or a combination thereof in the following PUCCH-PowerControl IE set as RRC.

In more detail, the TRP index may correspond to the p0-PUCCH-Id value set for PUCCH power control. For example, when p0-PUCCH-Id has a value between 1 and 4, it may correspond to TRP index 0, and when p0-PUCCH-Id has a value between 5 and 8, it may correspond to TRP index 1. The mapping between the range of the p0-PUCCH-Id and the TRP index may be changed. Alternatively, the TRP index may correspond to a pathlossReferenceRS configured for PUCCH power control. Alternatively, the TRP index may correspond to a power control adjustment state index set for PUCCH power control. The power control adjustment state index is an indicator indicating the power control state of the PUCCH resource, and may also be referred to as an expression such as a closed loop power control index and a TRP/panel specific closed loop power control index. When the twoPUCCH-PC-AdjustmentStates value of the RRC parameter is set to twoStates, the power control adjustment state index may have one of two values, e.g., a value expressed as i0 or i1, where i0 is TRP index 0, i1 May correspond to TRP index 1. The i0 or i1 mentioned above may be indicated in the form of a closedLoopIndex parameter value in spatial relation info activated for each PUCCH/PUCCH group as follows.

As described above, among PUCCH resources, a resource in which the closedLoopIndex parameter connected to spatial relation info is set to i0 is a PUCCH resource corresponding to TRP index 0, and a resource in which the closedLoopIndex parameter is set to i1 can be viewed as a PUCCH resource corresponding to TRP index 1. have.

On the other hand, the power control adjustment state index can be extended so that two can be set per TRP. Therefore, if the number of TRPs is supported up to 2, the total configurable power control adjustment state index can be extended to be set up to 4. For example, FourStates may be set as the value of the twoPUCCH-PC-AdjustmentStates parameter, or a new parameter such as the fourPUCCH-PC-AdjustmentStates parameter may be set. At this time, if the closedLoopIndex parameter connected to the spatial relation info is set to i0, i1, TRP index 0, the closedLoopIndex parameter is set to i2, i3, or a new parameter in the spatial relation info, for example, closedLoopIndexNew parameter, is additionally set. It can be seen as 1. In addition, as described above, a connection relationship between the PUCCH resource and the TRP index can be established.

Alternatively, if the overlapped PUCCH beams / TRP are different from each other, the base station may instruct the multiplexing configuration so as not to perform multiplexing. For example, when the above-described simultaneousHARQ-ACK-CSI is set, in Case 2, the UE may not expect a situation in which the PUCCH resource for transmitting HARQ-ACK and the PUCCH resource for transmitting CSI overlap. In this case, the inter-PUCCH beam/TRP may indicate the aforementioned TRP index.

In the case of Intra-slot TDMed separate HARQ-ACK, constraints for simplification of the overlap processing method between PUCCHs may be set. For example, the PUCCH format of a PUCCH resource for HARQ-ACK transmission may be limited, and the corresponding format may be short PUCCH, that is, format 0 and format 2, or some of them. It is also possible to be limited to Long PUCCH or some of them. Alternatively, in the case of Intra-slot TDMed separate HARQ-ACK, it is possible to not expect multiplexing between HARQ-ACK and CSI to be configured, or to ignore the multiplexing between HARQ-ACK and CSI and always be limited to drop the overlapped CSI.

Meanwhile, the above-mentioned method can be similarly applied even when multi-slot repetition is set. Therefore, for specific details, refer to the above.

Or, if multi-slot repetition is set, multiplexing is not allowed between overlapping PUCCHs similar to Rel-15, and slots overlapping the PUCCH resource or UCI with a lower priority according to the priority in the order of HARQ-ACK> SR> CSI Can be dropped from. Therefore, when a plurality of CSIs are multiplexed, priority between CSIs may be applied.

Meanwhile, multiplexing or drop may occur even when PUCCH and PUSCH overlap. In this case, the PUCCH and the PUSCH may be scheduled in the same serving cell or component carrier (CC), or may be scheduled in the same cell group or another serving cell/CC belonging to the same PUCCH group. In this case, a plurality of PUCCHs and a single PUSCH for HARQ-ACK transmission are overlapped similarly to Case 1 within the same cell group or the same PUCCH group, or a single PUCCH for HARQ-ACK / SR / CSI transmission is similar to Case 2 A single PUSCH overlaps, or multiple PUSCHs scheduled for multiple serving cells / CC and a single / multiple PUSCH overlap may occur. At this time, a TRP index is set for each CORESET in which DCI scheduling a PUSCH is transmitted in each serving cell/CC, and a TRP index may also be set for the PUCCH overlapped with these PUSCHs. When multiplexing between the overlapped PUCCH and PUSCH, the PUCCH may be multiplexed to the PUSCH corresponding to the lowest serving cell/CC index among the PUSCHs corresponding to the same value as the TRP index of the PUCCH. If there is no PUSCH corresponding to the same value as the TRP index of the corresponding PUCCH, the corresponding PUCCH may be dropped or the PUSCH may be dropped according to a preset priority. For example, when the PUCCH includes HARQ-ACK, the PUSCH is dropped, and when the PUCCH includes CSI and the PUSCH also includes CSI, the PUCCH may be dropped. If the TRP index is not set in the PUSCH, drop or multiplexing may be performed according to a rule set in Rel-15.

In this case, the TRP or TRP index of the PUCCH can be obtained according to the above-described method. For example, the TRP index may be expressed as a parameter set for PUCCH power control. For example, the TRP index may be expressed as one of the following values or a combination thereof in the following PUCCH-PowerControl IE set as RRC.

In more detail, the TRP index may correspond to the p0-PUCCH-Id value set for PUCCH power control. For example, when p0-PUCCH-Id has a value between 1 and 4, it may correspond to TRP index 0, and when p0-PUCCH-Id has a value between 5 and 8, it may correspond to TRP index 1. The mapping between the range of the p0-PUCCH-Id and the TRP index may be changed. Alternatively, the TRP index may correspond to a pathlossReferenceRS configured for PUCCH power control. Alternatively, the TRP index may correspond to a power control adjustment state index set for PUCCH power control. The power control adjustment state index is an indicator indicating the power control state of the PUCCH resource, and may also be referred to as an expression such as a closed loop power control index and a TRP/panel specific closed loop power control index. When the twoPUCCH-PC-AdjustmentStates value of the RRC parameter is set to twoStates, the power control adjustment state index may have one of two values, e.g., a value expressed as i0 or i1, where i0 is TRP index 0, i1 May correspond to TRP index 1. The i0 or i1 mentioned above may be indicated in the form of a closedLoopIndex parameter value in spatial relation info activated for each PUCCH/PUCCH group as follows.

As described above, among PUCCH resources, a resource in which the closedLoopIndex parameter connected to spatial relation info is set to i0 is a PUCCH resource corresponding to TRP index 0, and a resource in which the closedLoopIndex parameter is set to i1 can be viewed as a PUCCH resource corresponding to TRP index 1. have.

On the other hand, the power control adjustment state index can be extended so that two can be set per TRP. Therefore, if the number of TRPs is supported up to 2, the total configurable power control adjustment state index can be extended to be set up to 4. For example, FourStates may be set as the value of the twoPUCCH-PC-AdjustmentStates parameter, or a new parameter such as the fourPUCCH-PC-AdjustmentStates parameter may be set. At this time, if the closedLoopIndex parameter connected to the spatial relation info is set to i0, i1, TRP index 0, the closedLoopIndex parameter is set to i2, i3, or a new parameter in the spatial relation info, for example, closedLoopIndexNew parameter, is additionally set. It can be seen as 1. In addition, as described above, a connection relationship between the PUCCH resource and the TRP index can be established. The above connection relationship can be similarly applied between a parameter for PUSCH power control and a TRP index.

<Fourth Example; PUCCH resource selection method for multi-PDCCH-based NC-JT>

In this embodiment, when two or more PUCCH resources overlap, it proposes a method of selecting a PUCCH resource for multiplexing.

Case i. When two or more PUCCH resources overlap, when the PUCCH for grant-based HARQ-ACK transmission is included, the PUCCH resource indicated by the PRI (9-40, 9-41) for the HARQ-ACK in the PDCCH as described above Among them, only the PUCCH resource (9-31) selected based on the PRI (9-41) corresponding to the PDCCH (9-11) transmitted at the last point is selected and transmitted. At this time, the selected PUCCH resource is selected based on the payload of the UCI to be transmitted as described above. That is, a PUCCH resource set having a minimum payload that is not smaller than the UCI payload is selected. Next, the PUCCH resource set indicated by the PRI in the corresponding PUCCH resource set is selected.

If the overlapped PUCCH resource contained UCI transmitted to different TRP, the dropping rule as described in Example 3 may be applied.

If the overlapped PUCCH resource contained UCI to be transmitted to the same TRP, a method of ensuring that the selected PUCCH resource according to the payload of the multiplexed UCI can also be transmitted to the same TRP is required. For this, at least one of the following methods can be considered.

Method 1. Within the PUCCH resource set, select only the PUCCH resource corresponding to the target TRP of the UCI to be multiplexed.

Method 2. In the PUCCH resource set, the PUCCH resource that does not correspond to the target TRP of the UCI to be multiplexed is excluded. That is, select one of the PUCCH resource corresponding to the target TRP and the PUCCH resource for which the target TRP is not set.

Method 3. PUCCH resource set and PUCCH resource selection according to the above-described Rel-15-based method. At this time, it is assumed that the target TRP of the selected PUCCH resource corresponds to the target TRP of the multiplexed UCI.

In this case, in the case of HARQ-ACK, the target TRP of UCI may be a higher layer index set in CORESET in which DCI corresponding to the HARQ-ACK is transmitted, for example, a CORESET group index or a TRP index. Meanwhile, in the case of CSI, the target TRP may be a CORESET group index or a TRP index corresponding to the CSI report/resource setting. Alternatively, the HARQ-ACK or CSI may be a TRP identification factor corresponding explicitly/implicitly to the PUCCH resource to be transmitted, and the corresponding TRP identification factor may be one of a CORESET group index / TRP index / serving cell index. Alternatively, a PUCCH resource group to which a corresponding PUCCH resource belongs or a group / set index corresponding to a PUCCH resource set may be used as a TRP identification factor.

Meanwhile, the target TRP corresponding to the PUCCH resource may be a TRP identification factor corresponding to the corresponding PUCCH resource explicitly/implicitly, and the corresponding TRP identification factor may be one of a CORESET group index / TRP index / serving cell index. Alternatively, a PUCCH resource group to which a corresponding PUCCH resource belongs or a group / set index corresponding to a PUCCH resource set may be used as a TRP identification factor. Alternatively, in the third embodiment, it may be expressed as one of the above-described PUCCH power control parameters or a combination thereof, and the parameter may be the aforementioned p0-PUCCH-Id value, pathlossReferenceRS, and power control adjustment state index. If the power control adjustment state index is used, the TRP identification factor may be a corresponding TRP index from the power control adjustment state index as described above.

If the PUCCH resource selected according to one of the above methods overlaps with another PUCCH resource, the above-described UCI multiplexing and PUCCH resource selection process may be reapplied if the target TRP of these PUCCH resources is the same. If the target TRPs of these PUCCH resources are different, the dropping rule as described in Embodiment 3 may be applied.

Case ii. When two or more PUCCH resources are overlapped, each of the PUCCH resources is a resource for CSI transmission, or if the configured grant-based HARQ-ACK and one or more CSI are overlapped, multiplexing between multiple CSIs as described above is a higher layer If set, all of the multiplexed UCI payloads in the PUCCH resource list for CSI multiplexing set to the upper layer, such as multi-CSI-PUCCH-ResourceList, can be transmitted, and the UCI payload is transmitted after selecting one resource with the lowest index. . If there is no resource capable of transmitting all of the multiplexed UCI payloads in the list, select the resource with the largest index and transmit as many CSI reports as possible to the corresponding resource.

If the overlapped PUCCH resource contained UCI transmitted to different TRP, the dropping rule as described in Example 3 may be applied.

If the overlapped PUCCH resource contained UCI to be transmitted to the same TRP, a method of ensuring that the selected PUCCH resource according to the payload of the multiplexed UCI can also be transmitted to the same TRP is required. For this, at least one of the following methods can be considered.

Method 1. In the multi-CSI-PUCCH-ResourceList, select only the PUCCH resource corresponding to the target TRP of the UCI to be multiplexed.

Method 2. In the multi-CSI-PUCCH-ResourceList, the PUCCH resource that does not correspond to the target TRP of the UCI to be multiplexed is excluded. That is, select one of the PUCCH resource corresponding to the target TRP and the PUCCH resource for which the target TRP is not set.

Method 3. Select a PUCCH resource from the multi-CSI-PUCCH-ResourceList according to the Rel-15-based method described above. At this time, it is assumed that the target TRP of the selected PUCCH resource corresponds to the target TRP of the multiplexed UCI.

At this time, the target TRP of UCI and the target TRP of PUCCH resource can be confirmed according to the method described above (eg, Case i.).

If the PUCCH resource selected according to one of the above methods overlaps with another PUCCH resource, the above-described UCI multiplexing and PUCCH resource selection process may be reapplied if the target TRP of the overlapping PUCCH resources is the same. If the target TRPs of these PUCCH resources are different, the dropping rule as described in Embodiment 3 may be applied.

Case iii. When an overlap occurs between the PUCCH resource and the PUSCH, Rel-15 describes a procedure for multiplexing the UCI of the PUCCH to the PUSCH and then transmitting only the PUSCH, or dropping the PUSCH without PUCCH-PUSCH multiplexing. At this time, the PUCCH and PUSCH in which the overlap occurs may belong to the same serving cell, may belong to the same cell group or another serving cell belonging to the same PUCCH group.

If the overlapped PUCCH resource and the target TRP of the PUSCH are different from each other, a dropping rule similar to that described in the above (eg, Example 3) may be applied.

If the overlapped PUCCH resource and the target TRP of the PUSCH are the same, there is a need for a method of ensuring that these multiplexed PUSCHs can also be designated as the same target TRP. For this, at least one of the following methods can be considered.

Method 1. Within the PUCCH and the overlapped PUSCH, select one PUSCH corresponding to the target TRP of the UCI to be multiplexed according to a predetermined rule. The rules may be the same as those described in the third embodiment.

Method 2. Within the PUCCH and the overlapped PUSCH, exclude the PUSCH that does not correspond to the target TRP of the UCI to be multiplexed. That is, one of the PUSCH corresponding to the target TRP and the PUSCH for which the target TRP is not set is selected. The rules may be the same as those described in the third embodiment.

Method 3. According to the Rel-15-based method, the PUSCH to be multiplexed is selected regardless of whether the target TRP value of the PUSCH or the target TRP is set. At this time, it is assumed that the target TRP of the selected PUSCH corresponds to the target TRP of the multiplexed UCI. In this case, the target TRP of the UCI and the target TRP of the PUCCH resource are according to the method described above (e.g., Case i.) I can confirm. The target TRP of the PUSCH can be checked through the TRP index set in the CORESET in which the DCI scheduling the corresponding PUSCH is transmitted, or the beam for the corresponding PUSCH transmission, e.g., the TPMI indicated by the DCI scheduling the corresponding PUSCH, or the SRS specified as SRI or SRI. You can check it with the connected spatialRelationInfo.

When the PUSCH selected according to one of the above methods overlaps with other PUCCH resources, the above-described multiplexing process may be reapplied if the target TRP of these PUSCHs and PUCCH resources are the same. If the target TRP of these PUSCH and PUCCH resources are different, the dropping rule as described in the third embodiment may be applied.

Meanwhile, in the method proposed in the present invention, some components may be omitted and only some components may be included within a range that does not impair the essence of the present invention.

In addition, the method proposed in the present invention may be implemented by combining some or all of the contents included in each embodiment within the scope not impairing the essence of the invention.

<Fourth Example; HARQ-ACK codebook generation method for repeated transmission NC-JT>

NC-JT may be used to improve reliability of repeated PDSCH transmission. Repeated NC-JT PDSCH transmission may be performed through different time resources. For example, the PDSCH may be repeatedly transmitted for each slot over a plurality of slots, or the PDSCH may be repeatedly transmitted within one slot. A single PDCCH may be used to schedule the repetitive transmission. The DCI of the PDCCH may indicate a list of all TRPs that will participate in repetitive transmission. The list of TRPs to be repeatedly transmitted may be indicated in the form of a TCI state list, and the length of the TCI state list may be dynamically changed.

When the PDSCH is repeatedly transmitted over multiple slots, the time and frequency resources of the first transmitted PDSCH are indicated by DCI, and the time and frequency resources in the slot allocated to the repeatedly transmitted PDSCH for each slot may be the same. If the number of repetitive transmissions is greater than the number of TCI states, a specific pattern may be followed when the TCI state is applied to each repetition slot. For example, if the number of repetitive transmissions is 4 and TCI state indexes 1 and 2 are indicated, the TCI state can be applied to each of the transmission slots according to the pattern of 1, 2, 1, 2 or 1, 1, 2, 2 have. In addition, the number of repetitive transmissions may be dynamically indicated through DCI/MAC-CE. For example, the number of repetitive transmissions may be indicated through a time domain resource allocation field indicated by DCI. For example, through the time domain resource allocation field of the DCI, the number of repetitive transmissions may be indicated in addition to a value indicated by the current NR, for example, values such as K _{0, S, and L described above in FIG. 8.}

When the PDSCH is repeatedly transmitted in one slot, the time and frequency resources of the first PDSCH transmitted in the slot are indicated by DCI, and the symbol length and frequency resources allocated for each repeatedly transmitted PDSCH may be the same. An offset for each PDSCH that is repeatedly transmitted may be set in units of symbols. For example, the next repeated transmission PDSCH may be transmitted after a symbol separated by a set offset based on the last symbol of the first repeated transmission PDSCH.

For convenience of technology, the repetitive transmission method has been described as an example of NC-JT, but the repetitive transmission method is similarly applicable to single TRP-based transmission. For example, a method in which the number of repetitive transmissions is dynamically indicated through a time domain resource allocation field indicated by DCI is similarly applicable to single TRP-based transmission.

When repetitive transmission is configured according to the above embodiment, the HARQ-ACK codebook generation method may be different for each repetitive transmission method. That is, different HARQ-ACK codebook generation methods can be applied according to repetitive transmission within a slot or repetition transmission across multiple slots. In this embodiment, for the convenience of technology, the description focuses on the type 1 HARQ-ACK codebook.

16A, 16B, and 16C show a type 1 HARQ- for each of the repeated PDSCH transmission NC-JT in a single slot and the repeated PDSCH transmission NC-JT across multiple slots when there is no repetition transmission according to an embodiment of the present disclosure. A diagram showing methods of generating an ACK codebook

First, when there is no repeated transmission (16-00), a set of reception candidate cases M _A,c is configured according to pseudo-code 1, and corresponding to each reception candidate in _{the set M A,c according to pseudo-code 2} The HARQ-ACK feedback bit is determined according to whether the PDSCH is received. Whether the PDSCH #1 (16-10) and PDSCH #2 (16-20) are received is configured as a HARQ-ACK codebook (16-40), respectively, and may be transmitted as a PUCCH resource (16-30) or a PUSCH resource. .

Next, when intra-slot repetitive transmission is set (16-50), the set M _A,c of reception candidate cases is configured according to the pseudo-code 1, and each reception in _{the set M A,c} according to pseudo-code 2 The HARQ-ACK feedback bit is determined according to whether the PDSCH corresponding to the candidate is received. Meanwhile, in pseudo-code 2, the HARQ-ACK feedback bit is determined for the first repeatedly transmitted PDSCH according to whether the repeatedly transmitted PDSCH is received, whereas the HARQ-ACK feedback bit is omitted for the second and subsequent PDSCHs, or the corresponding PDSCH In the case of a reception candidate corresponding to, that is, a HARQ-ACK feedback bit may be determined as NACK at a position corresponding to a corresponding PDSCH among _{M A and c.} In addition, when the intra-slot repetitive transmission is set, repetitive transmission over multiple slots may not be set at the same time, and thus, in this case, the number of transmission slots can be regarded as one slot.

Next, when repetitive transmission over multiple slots is set (16-90), repetitive transmission PDSCH (16-92) to PUCCH (16-95) transmitted in the slot corresponding to the K1 value from the last slot in which the PDSCH is repeatedly transmitted HARQ-ACK feedback bit can be transmitted. For PUCCHs 16-94 of the remaining slots, when HARQ-ACK is transmitted according to the pseudo-code 1 and pseudo-code 2, a reception candidate corresponding to the repetitive transmission PDSCH, that is, the corresponding PDSCH among _{M A and c} The HARQ-ACK feedback bit may be determined as NACK at the corresponding position.

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

Referring to FIG. 17, the terminal may include a transceiver 17-00, a memory 17-05, and a processor 17-10. According to the above-described communication method of the terminal, the transmission/reception unit 17-00 and the processor 17-10 of the terminal may operate. However, the components of the terminal are not limited to the above-described example. For example, the terminal may include more or fewer components than the above-described components. In addition, the transmission/reception unit 17-00, the memory 17-05, and the processor 17-10 may be implemented in the form of a single chip.

The transmission/reception unit 17-00 may transmit and receive signals to and from the base station. Here, the signal may include control information and data. To this end, the transmission/reception unit 17-00 may include an RF transmitter that up-converts and amplifies a frequency of a transmitted signal, and an RF receiver that amplifies a received signal with low noise and down-converts a frequency. However, this is only an embodiment of the transmission/reception unit 17-00, and components of the transmission/reception unit 17-00 are not limited to the RF transmitter and the RF receiver.

Also, the transceiver 17-00 may receive a signal through a wireless channel, output it to the processor 17-10, and transmit a signal output from the processor 17-10 through a wireless channel.

The memories 17-05 may store programs and data necessary for the operation of the terminal. In addition, the memory 17-05 may store control information or data included in signals transmitted and received by the terminal. The memories 17-05 may be formed of a storage medium such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. Also, there may be a plurality of memories 17-05.

In addition, the processor 17-10 may control a series of processes so that the terminal can operate according to the above-described embodiment. For example, the processor 17-10 may control the components of the terminal to receive a DCI composed of two layers and simultaneously receive a plurality of PDSCHs. There may be a plurality of processors 17-10, and the processor 17-10 may perform a component control operation of the terminal by executing a program stored in the memory 17-05.

18 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. 18, a base station may include a transceiver 18-00, a memory 18-05, and a processor 18-10. According to the above-described communication method of the base station, the transmission/reception unit 18-00 and the processor 18-10 of the base station may operate. However, the components of the base station are not limited to the above-described example. For example, the base station may include more or fewer components than the above-described components. In addition, the transmission/reception unit 18-00, the memory 18-05, and the processor 18-10 may be implemented in the form of a single chip.

The transceiving unit 18-00 may transmit and receive signals to and from the terminal. Here, the signal may include control information and data. To this end, the transmission/reception unit 18-00 may include an RF transmitter that up-converts and amplifies a frequency of a transmitted signal, and an RF receiver that amplifies a received signal with low noise and down-converts a frequency. However, this is only an embodiment of the transmission/reception unit 18-00, and components of the transmission/reception unit 18-00 are not limited to the RF transmitter and the RF receiver.

In addition, the transmission/reception unit 18-00 may receive a signal through a wireless channel, output it to the processor 18-10, and transmit a signal output from the processor 18-10 through a wireless channel.

The memories 18-05 may store programs and data required for the operation of the base station. In addition, the memories 18-05 may store control information or data included in signals transmitted and received by the base station. The memories 18-05 may be composed of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. Also, there may be a plurality of memories 18-05.

The processor 18-10 may control a series of processes so that the base station can operate according to the above-described embodiment of the present disclosure. For example, the processor 18-10 may control each component of the base station to configure and transmit DCIs of two layers including allocation information for a plurality of PDSCHs. There may be a plurality of processors 18-10, and the processors 18-10 may perform component control operations of the base station by executing programs stored in the memory 18-05.

The methods according to the embodiments described in the claims or the 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 to be executable by one or more processors in an electronic device (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.

These programs (software modules, software) 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 types of It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all of them. In addition, a plurality of configuration memories may be included.

In addition, the program is accessed through a communication network such as the Internet, Intranet, LAN (Local Area Network), WLAN (Wide LAN), or SAN (Storage Area Network), or a communication network composed of a combination thereof. It may be stored in an (access) attachable storage device. 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 the communication network may access a device performing an embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, the constituent elements included in the invention are expressed in the singular or plural according to the presented specific embodiment. However, the singular or plural expression is selected appropriately for the situation presented for convenience of description, and the present disclosure is not limited to the singular or plural constituent elements, and even constituent elements expressed in plural are composed of the singular or in the singular. Even the expressed constituent elements may be composed of pluralities.

Meanwhile, the embodiments of the present disclosure disclosed in the present specification and drawings are merely provided with specific examples to easily describe the technical content of the present disclosure and to aid understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. That is, that other modified examples based on the technical idea of the present disclosure may be implemented is obvious to those of ordinary skill in the technical field to which the present disclosure belongs. In addition, each of the above embodiments can be operated in combination with each other as needed. For example, portions of an embodiment of the present disclosure and another embodiment may be combined with each other to operate a base station and a terminal. For example, parts of the first and second embodiments of the present disclosure may be combined with each other to operate a base station and a terminal. In addition, although the above embodiments have been presented based on the FDD LTE system, other systems such as the TDD LTE system, 5G, or NR system may also be implemented with other modifications based on the technical idea of the embodiment.

On the other hand, in the drawings for explaining the method of the present invention, the order of description does not necessarily correspond to the order of execution, and the relationship between precedence and subsequent changes or may be executed in parallel.

Alternatively, in the drawings for explaining the method of the present invention, some components may be omitted and only some components may be included within the scope not impairing the essence of the present invention.

In addition, the method of the present invention may be implemented by combining some or all of the contents included in each embodiment within the scope not impairing the essence of the invention.

Claims (1)

In the 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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