Method and apparatus for determining priority for reception of downlink control information in wireless communication system

Abstract

The present disclosure relates to a communication technique for merging IoT technology with a 5G communication system for supporting a data transmission rate higher than that of a 4G system, and a system therefor. The present disclosure can be applied to intelligent services (for example, smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail businesses, security- and safety-related services, and the like) on the basis of 5G communication technology and IoT-related technology. The present disclosure may provide a method and an apparatus for determining a priority for reception of downlink control information in a wireless communication system.

Description

Method and device for determining priority for receiving downlink control information in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a method for determining a priority for receiving downlink control information in a wireless communication system and a device capable of performing the same.

[0002] To meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems, efforts are being made to develop improved 5G communication systems, or pre-5G communication systems. For this reason, 5G communication systems, or pre-5G communication systems, are also called beyond 4G networks or post-LTE systems. To achieve high data rates, 5G communication systems are being considered for implementation in ultra-high frequency (mmwave) bands (e.g., 60 gigahertz (80 GHz) bands). To mitigate path loss and increase transmission range of radio waves in ultra-high frequency bands, beamforming, massive MIMO, full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large-scale antenna technologies are being discussed in 5G communication systems. Additionally, to improve the network of the system, technologies such as evolved small cells, advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device to device communication (D2D), wireless backhaul, moving networks, cooperative communication, coordinated multi-points (CoMP), and interference cancellation are being developed in 5G communication systems.In addition, advanced coding modulation (ACM) methods such as hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC), as well as advanced access technologies such as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) are being developed in 5G systems.

[0003] Meanwhile, the Internet is evolving from a human-centric network where humans create and consume information to the Internet of Things (IoT), where information is exchanged and processed between distributed components such as objects. The Internet of Everything (IoE) is also emerging, combining IoT technologies with big data processing technologies such as cloud servers. To implement the IoT, technological elements such as sensing technologies, wired and wireless communication and network infrastructure, service interface technologies, and security technologies are required. Recently, research is being conducted on technologies such as sensor networks, machine-to-machine (M2M), and machine-type communication (MTC) for connecting objects. In the IoT environment, intelligent IT (Internet Technology) services can be provided that collect and analyze data generated from connected objects to create new value for human life. IoT can be applied to areas such as smart homes, smart buildings, smart cities, smart or connected cars, smart grids, healthcare, smart appliances, and advanced medical services through the convergence and integration of existing IT (Information Technology) technologies with various industries.

[0004] Accordingly, various attempts are being made to apply 5G communication systems (also known as new radio (NR)) to IoT networks. For example, technologies such as sensor networks, machine-to-machine (M2M) communication, and machine-type communication (MTC) are being implemented using 5G communication techniques such as beamforming, MIMO, and array antennas. The application of cloud radio access networks (cloud RAN), a big data processing technology described above, can also be considered an example of the convergence of 3eG and IoT technologies.

[0005] As described above and with the development of wireless communication systems, various services have become available, and methods for providing these services smoothly are required.

[0006] The present disclosure seeks to provide a device and method capable of effectively providing a service in a mobile communication system.

[0007] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0008] According to one embodiment, a method performed by a terminal in a communication system may be provided.

[0009] According to one embodiment, the method may include receiving, via higher layer signaling, (i) a configuration for a physical downlink control channel (PDCCH) repetition and (ii) a configuration for a plurality of control resource sets (CORESETs).

[0010] According to one embodiment, the method may include: identifying one or more CORESETs for PDCCH monitoring among the plurality of CORESETs, based on quasi co-location (QCL) Type-D configurations corresponding to the plurality of CORESETs and predefined QCL priorities, such that the number of QCL Type-D configurations for PDCCH monitoring is less than or equal to the maximum number supported by the terminal, when a CORESET pool index corresponding to some CORESETs among the plurality of CORESETs is set to 1; and receiving the PDCCH repetition based on PDCCH monitoring for the one or more CORESETs.

[0011] According to one embodiment, the CORESET full index corresponding to the remaining CORESETs excluding some of the CORESETs among the plurality of CORESETs may not be set or may be set to 0.

[0012] In one embodiment, when the maximum number is defined per CORESET pool index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the maximum number may be applied to each of the some CORESETs and the remaining CORESETs.

[0013] In one embodiment, when the maximum number is defined for the entire CORESET full index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the maximum number may be applied to the plurality of CORESETs.

[0014] According to one embodiment, the plurality of CORESETs may overlap in the time domain.

[0015] According to one embodiment, the plurality of CORESETs may include a plurality of SSs (search spaces).

[0016] According to one embodiment, in identifying the QCL priority, the CORESET full index may be considered in ascending order, then the indices of the plurality of CORESETs may be considered in ascending order, and then the indices of the plurality of SSs may be considered in ascending order.

[0017] According to one embodiment, when two SSs having the same linking identifier are included in the plurality of SSs, and a CORESET including a first SS among the two SSs is identified as being for the PDCCH monitoring, a CORESET including a second SS among the two SSs can be identified as being for the PDCCH monitoring.

[0018] According to one embodiment, when a first CORESET corresponding to a first CORESET full index among the CORESET full indices is identified as being for the PDCCH monitoring, a second CORESET corresponding to a second CORESET full index among the CORESET full indices and having a QCL Type-D setting that is the same as the QCL Type-D setting of the first CORESET may be identified as being for the PDCCH monitoring.

[0019] According to one embodiment, among the CORESET pool indices, the SS with the lowest index among the SSs included in the CORESET with the lowest index corresponding to the lowest CORESET pool index among the CORESET pool indices may be considered as the highest priority in identifying the QCL priority.

[0020] According to one embodiment, when information is received that sets a high priority for a specific CORESET pool index, in identifying the QCL priority, the specific CORESET pool index set to the high priority may be given priority instead of considering the CORESET pool indexes in ascending order.

[0021] According to one embodiment, when information setting a high priority for a specific connection identifier is received, in identifying the QCL priority, two SSs having the specific connection identifier may be given priority in identifying the QCL priority.

[0022] According to one embodiment, the method may further comprise the step of transmitting a terminal capability report including information about the maximum number.

[0023] According to one embodiment, the terminal capability report may further include information corresponding to at least one FG (feature group) identified according to a predefined rule among a plurality of predefined FGs in relation to whether the terminal supports an operation of identifying one or more CORESETs for PDCCH monitoring based on the QCL priority.

[0024] According to one embodiment, a terminal of a communication system may be provided.

[0025] According to one embodiment, the terminal may include a transceiver; and a processor connected to the transceiver.

[0026] According to one embodiment, the processor may be configured to receive, via higher layer signaling, (i) a configuration for physical downlink control channel (PDCCH) repetition and (ii) a configuration for a plurality of control resource sets (CORESETs).

[0027] According to one embodiment, the processor may be configured to: identify one or more CORESETs for PDCCH monitoring among the plurality of CORESETs, based on QCL (quasi co-location) Type-D configurations corresponding to the plurality of CORESETs and predefined QCL priorities, such that the number of QCL Type-D configurations for PDCCH monitoring is less than or equal to the maximum number supported by the terminal, when a CORESET pool index corresponding to some CORESETs among the plurality of CORESETs is set to 1; and receive the PDCCH repetition based on PDCCH monitoring for the one or more CORESETs.

[0028] According to one embodiment, the CORESET full index corresponding to the remaining CORESETs excluding some of the CORESETs among the plurality of CORESETs may not be set or may be set to 0.

[0029] In one embodiment, when the maximum number is defined per CORESET pool index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the maximum number may be applied to each of the some CORESETs and the remaining CORESETs.

[0030] In one embodiment, when the maximum number is defined for the entire CORESET full index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the maximum number may be applied to the plurality of CORESETs.

[0031] According to one embodiment, the plurality of CORESETs may overlap in the time domain.

[0032] According to one embodiment, the plurality of CORESETs may include a plurality of SSs (search spaces).

[0033] According to one embodiment, in identifying the QCL priority, the CORESET full index may be considered in ascending order, then the indices of the plurality of CORESETs may be considered in ascending order, and then the indices of the plurality of SSs may be considered in ascending order.

[0034] According to one embodiment, when two SSs having the same linking identifier are included in the plurality of SSs, and a CORESET including a first SS among the two SSs is identified as being for the PDCCH monitoring, a CORESET including a second SS among the two SSs can be identified as being for the PDCCH monitoring.

[0035] According to one embodiment, when a first CORESET corresponding to a first CORESET full index among the CORESET full indices is identified as being for the PDCCH monitoring, a second CORESET corresponding to a second CORESET full index among the CORESET full indices and having a QCL Type-D setting that is the same as the QCL Type-D setting of the first CORESET may be identified as being for the PDCCH monitoring.

[0036] According to one embodiment, among the CORESET pool indices, the SS with the lowest index among the SSs included in the CORESET with the lowest index corresponding to the lowest CORESET pool index among the CORESET pool indices may be considered as the highest priority in identifying the QCL priority.

[0037] According to one embodiment, when information is received that sets a high priority for a specific CORESET pool index, in identifying the QCL priority, the specific CORESET pool index set to the high priority may be given priority instead of considering the CORESET pool indexes in ascending order.

[0038] According to one embodiment, when information setting a high priority for a specific connection identifier is received, in identifying the QCL priority, two SSs having the specific connection identifier may be given priority in identifying the QCL priority.

[0039] According to one embodiment, the processor may be configured to transmit a terminal capability report including information about the maximum number.

[0040] According to one embodiment, the terminal capability report may further include information corresponding to at least one FG (feature group) identified according to a predefined rule among a plurality of predefined FGs in relation to whether the terminal supports an operation of identifying one or more CORESETs for PDCCH monitoring based on the QCL priority.

[0041] According to one embodiment, a method performed by a base station in a communication system may be provided.

[0042] According to one embodiment, the method may include transmitting to the terminal, via higher layer signaling, (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for a plurality of CORESETs (control resource sets).

[0043] According to one embodiment, the method may include transmitting the PDCCH repetition to the terminal based on one or more CORESETs among the plurality of CORESETs.

[0044] According to one embodiment, if a CORESET pool index corresponding to some of the plurality of CORESETs is 1, the one or more CORESETs may be based on a QCL (quasi co-location) type-D setting corresponding to the plurality of CORESETs and a predefined QCL priority.

[0045] According to one embodiment, the number of QCL type-D settings corresponding to the one or more CORESETs may be less than or equal to the maximum number supported by the terminal.

[0046] According to one embodiment, the plurality of CORESETs may overlap in the time domain.

[0047] According to one embodiment, the plurality of CORESETs may include a plurality of SSs (search spaces).

[0048] According to one embodiment, the QCL priority may be defined such that the CORESET full index is considered in ascending order, then the indices of the plurality of CORESETs are considered in ascending order, and then the indices of the plurality of SSs are considered in ascending order.

[0049] According to one embodiment, a base station of a communication system may be provided.

[0050] According to one embodiment, the base station may include a transceiver; and a processor connected to the transceiver.

[0051] According to one embodiment, the processor may be configured to: transmit to the terminal, via upper layer signaling, (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for a plurality of CORESETs (control resource sets).

[0052] According to one embodiment, the processor may be configured to transmit the PDCCH repetition to the terminal based on one or more CORESETs among the plurality of CORESETs.

[0053] According to one embodiment, if a CORESET pool index corresponding to some of the plurality of CORESETs is 1, the one or more CORESETs may be based on a QCL (quasi co-location) type-D setting corresponding to the plurality of CORESETs and a predefined QCL priority.

[0054] According to one embodiment, the number of QCL type-D settings corresponding to the one or more CORESETs may be less than or equal to the maximum number supported by the terminal.

[0055] According to one embodiment, the plurality of CORESETs may overlap in the time domain.

[0056] According to one embodiment, the plurality of CORESETs may include a plurality of SSs (search spaces).

[0057] According to one embodiment, the QCL priority may be defined such that the CORESET full index is considered in ascending order, then the indices of the plurality of CORESETs are considered in ascending order, and then the indices of the plurality of SSs are considered in ascending order.

[0058] According to one embodiment of the present disclosure, a device and method for effectively providing a service in a mobile communication system can be provided.

[0059] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

[0060] FIG. 1 is a diagram illustrating a basic structure of a time-frequency domain in a wireless communication system according to one embodiment of the present disclosure.

[0061] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to one embodiment of the present disclosure.

[0062] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to one embodiment of the present disclosure.

[0063] FIG. 4 is a diagram illustrating an example of setting a control region of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0064] FIG. 5a is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0065] FIG. 5b is a diagram illustrating a case in which a terminal can have multiple PDCCH monitoring positions within a slot through Span in a wireless communication system according to one embodiment of the present disclosure.

[0066] FIG. 6 is a diagram illustrating an example of DRX operation in a wireless communication system according to one embodiment of the present disclosure.

[0067] FIG. 7 is a diagram illustrating an example of base station beam allocation according to TCI state settings in a wireless communication system according to one embodiment of the present disclosure.

[0068] FIG. 8 is a diagram illustrating an example of a TCI state allocation method for a PDCCH in a wireless communication system according to one embodiment of the present disclosure.

[0069] FIG. 9 is a diagram illustrating a TCI indication MAC CE signaling structure for PDCCH DMRS in a wireless communication system according to one embodiment of the present disclosure.

[0070] FIG. 10 is a diagram illustrating an example of beam setting of CORESET and search space in a wireless communication system according to one embodiment of the present disclosure.

[0071] FIG. 11 is a diagram for explaining a method for a base station and a terminal to transmit and receive data in consideration of a downlink data channel and rate matching resources in a wireless communication system according to one embodiment of the present disclosure.

[0072] FIG. 12 is a diagram for explaining a method for selecting a receivable CORESET by considering priority when a terminal receives a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0073] FIG. 13 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation in a wireless communication system according to one embodiment of the present disclosure.

[0074] FIG. 14 is a diagram illustrating an example of antenna port configuration and resource allocation for cooperative communication in a wireless communication system according to one embodiment of the present disclosure.

[0075] FIG. 15 is a diagram illustrating an example of configuring downlink control information (DCI) for cooperative communication in a wireless communication system according to one embodiment of the present disclosure.

[0076] FIG. 16 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0077] FIG. 17 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0078] FIG. 18 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0079] FIG. 19 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0080] FIG. 20 is a diagram illustrating a method for determining a priority upon reception for PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0081] FIG. 21 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0082] FIG. 22 is a flowchart illustrating an operation of a terminal for receiving a repeatedly transmitted PDCCH according to one embodiment of the present disclosure.

[0083] FIG. 23 is a diagram showing an example of the operation of a terminal according to one embodiment of the present disclosure.

[0084] FIG. 24 is a diagram showing an example of the operation of a base station according to one embodiment of the present disclosure.

[0085] FIG. 25 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0086] FIG. 26 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0087] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0088] In describing the embodiments, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to ensure that the gist of the present disclosure is conveyed more clearly without obscuring it by omitting unnecessary explanations.

[0089] For the same reason, some components in the attached drawings may be exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component may not fully reflect its actual size. Identical or corresponding components in each drawing may be assigned the same reference number.

[0090] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals may refer to like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, the detailed description thereof may be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and may vary depending on the intention or custom of the user or operator. Therefore, the definitions should be made based on the contents throughout the specification.

[0091] Hereinafter, the base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (base station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (user equipment), an MS (mobile station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) may refer to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) may refer to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although an LTE or LTE-A system may be described below as an example, embodiments of the present disclosure may also be applied to other communication systems having a similar technical background or channel type. For example, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included here, and 5G below may also refer to a concept that includes existing LTE, LTE-A, and other similar services. In addition, the present disclosure may be applied to other communication systems with some modifications within a scope that does not significantly deviate from the scope of the present disclosure, as judged by a person having skilled technical knowledge.

[0092] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0093] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0094] Here, the term '~ unit' used in this embodiment means software or hardware components such as FPGA (field programmable gate array) or ASIC (application specific integrated circuit), and the '~ unit' can perform certain roles. However, the '~ unit' is not limited to software or hardware. The '~ unit' may be configured to be on an addressable storage medium and may be configured to play one or more processors. Accordingly, as an example, the '~ unit' may include components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~parts' may include one or more processors.

[0095] Wireless communication systems are evolving from providing voice-oriented services in the early days to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards such as 3GPP's HSPA (high speed packet access), LTE (long term evolution or E-UTRA (evolved universal terrestrial radio access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's HRPD (high rate packet data), UMB (ultra mobile broadband), and IEEE's 802.16e.

[0096] As a representative example of the above broadband wireless communication system, the LTE system adopts the orthogonal frequency division multiplexing (OFDM) method in the downlink (DL) and the single carrier frequency division multiple access (SC-FDMA) method in the uplink (UL). The uplink refers to a wireless link in which a terminal (user equipment (UE) or mobile station (MS)) transmits data or control signals to a base station (eNode B or base station (BS)), and the downlink refers to a wireless link in which a base station transmits data or control signals to a terminal. The above multiple access method can distinguish the data or control information of each user by allocating and operating the time-frequency resources for transmitting data or control information to each user so that they do not overlap, that is, so that orthogonality is established.

[0097] As a future communication system beyond LTE, 5G communication systems must be able to freely reflect the diverse needs of users and service providers. Therefore, they must support services that simultaneously satisfy these diverse requirements. Services being considered for 5G communication systems include enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable low-latency communication (URLLC).

[0098] eMBB aims to provide data transmission rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to support a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink from the perspective of a single base station. Furthermore, 5G communication systems must provide not only the peak data rate but also the increased user-perceived data rate for terminals. To meet these requirements, improvements in various transmission and reception technologies, including improved multi-input, multi-output (MIMO) transmission technology, are required. Furthermore, while LTE transmits signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the data transmission rates required by 5G communication systems by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher frequency bands.

[0099] At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide the IoT, mMTC requires supporting large-scale terminal connections within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. The IoT requires the ability to support a large number of terminals (e.g., 1,000,000 terminals / km2) within a cell, as it provides communication capabilities through the attachment of various sensors and devices. Furthermore, due to the nature of the service, terminals supporting mMTC are likely to be located in shadow areas, such as basements, beyond cell coverage. Therefore, they may require broader coverage compared to other services provided by 5G communication systems. Terminals supporting mMTC must be inexpensive, and since frequent battery replacement is unlikely, they may require extremely long battery lifespans, such as 10 to 15 years.

[0100] Finally, URLLC refers to cellular-based wireless communication services used for specific mission-critical purposes. Examples include remote control of robots or machinery, industrial automation, unmanaged aerial vehicles, remote health care, and emergency alerts. Therefore, URLLC communications must offer extremely low latency and high reliability. For example, services supporting URLLC must meet air interface latency requirements of less than 0.5 milliseconds and a packet error rate of less than 10-5. Therefore, for services supporting URLLC, 5G systems must provide shorter transmit time intervals (TTIs) than other services, and design considerations may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0101] The three 5G services—eMBB, URLLC, and mMTC—can be multiplexed and transmitted within a single system. To meet the differing requirements of each service, different transmission and reception techniques and parameters can be used. Of course, 5G is not limited to the three services described above.

[0102] [NR time-frequency resources]

[0103] Below, the frame structure of the 5G system is described in more detail with reference to drawings.

[0104] Figure 1 is a diagram illustrating the basic structure of the time-frequency domain, which is a radio resource domain in which data or control channels are transmitted in a 5G system.

[0105] The horizontal axis of Figure 1 represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time and frequency domains is a resource element (RE, 101), which can be defined as 1 OFDM symbol (102) on the time axis and 1 subcarrier (103) on the frequency axis. In the frequency domain (For example, 12) consecutive REs can constitute one resource block (RB, 104). One subframe (110) on the time axis can include multiple OFDM symbols (102). For example, the length of one subframe can be 1 ms.

[0106] FIG. 2 is a diagram illustrating a frame, subframe, and slot structure in a wireless communication system according to one embodiment of the present disclosure.

[0107] Figure 2 illustrates an example of a structure of a frame (Frame, 200), a subframe (Subframe, 201), and a slot (Slot, 202). One frame (200) can be defined as 10ms. One subframe (201) can be defined as 1ms, and therefore one frame (200) can be composed of a total of 10 subframes (201). One slot (202, 203) can be defined as 14 OFDM symbols (i.e., the number of symbols per slot ( =14). 1 subframe (201) may be composed of one or more slots (202, 203), and the number of slots (202, 203) per 1 subframe (201) may vary depending on the setting value μ (204, 205) for the subcarrier spacing. In an example of FIG. 2, cases where the subcarrier spacing setting value μ = 0 (204) and μ = 1 (205) are illustrated. When μ = 0 (204), 1 subframe (201) may be composed of one slot (202), and when μ = 1 (205), 1 subframe (201) may be composed of two slots (203). That is, the number of slots per 1 subframe ( ) may vary, and accordingly the number of slots per frame ( ) may vary. Depending on the subcarrier spacing setting μ and can be defined as [Table 1] below.

[0108] [Table 1]

[0109]

[0110] [Bandwidth Part (BWP)]

[0111] Next, the bandwidth part (BWP) setting in the 5G communication system will be explained in detail with reference to the drawing.

[0112] FIG. 3 is a diagram illustrating an example of bandwidth portion settings in a wireless communication system according to one embodiment of the present disclosure.

[0113] FIG. 3 shows an example in which the UE bandwidth (300) is set to two bandwidth portions, namely, bandwidth portion #1 (BWP#1) (301) and bandwidth portion #2 (BWP#2) (302). The base station can set one or more bandwidth portions to the UE, and can set the information in [Table 2] below for each bandwidth portion.

[0114] [Table 2]

[0115]

[0116] Of course, the above example is not limited, and in addition to the above configuration information, various parameters related to the bandwidth portion can be configured for the terminal. The above information can be transmitted from the base station to the terminal via upper layer signaling, for example, RRC (Radio Resource Control) signaling. At least one bandwidth portion among the configured one or more bandwidth portions can be activated. Whether or not the configured bandwidth portion is activated can be semi-statically transmitted from the base station to the terminal via RRC signaling or dynamically transmitted via DCI.

[0117] According to some embodiments, a terminal before RRC connection can be configured with an initial bandwidth portion (Initial BWP) for initial access from a base station through a Master Information Block (MIB). More specifically, the terminal can receive configuration information about a control resource set (CORESET) and a search space in which a PDCCH for receiving system information required for initial access (which may correspond to Remaining System Information (RMSI) or System Information Block 1 (SIB1)) and search space can be transmitted through the MIB during the initial access phase. The control space and search space configured by the MIB can each be regarded as identifier (ID) 0. The base station can notify the terminal of configuration information such as frequency allocation information, time allocation information, and numerology for control space #0 through the MIB. Additionally, the base station can notify the terminal of the monitoring cycle and monitoring occasion settings for control area #0, i.e., search space #0, via the MIB. The terminal can consider the frequency range set as control area #0 obtained from the MIB as the initial bandwidth portion for initial access. At this time, the identifier (ID) of the initial bandwidth portion can be considered as 0.

[0118] The settings for the bandwidth supported by the above 5G can be used for various purposes.

[0119] In some embodiments, when the bandwidth supported by a terminal is smaller than the system bandwidth, this can be supported through bandwidth portion configuration. For example, the base station can configure the bandwidth portion frequency location (configuration information 2) for the terminal, thereby allowing the terminal to transmit and receive data at a specific frequency location within the system bandwidth.

[0120] Additionally, in some embodiments, a base station may configure multiple bandwidth segments for a terminal to support different numerologies. For example, to support data transmission and reception using both 15 kHz and 30 kHz subcarrier spacing for a given terminal, two bandwidth segments may be configured with subcarrier spacings of 15 kHz and 30 kHz, respectively. The different bandwidth segments may be frequency-division multiplexed (FDM), and when data is to be transmitted and received using a specific subcarrier spacing, the bandwidth segment configured for that subcarrier spacing may be activated.

[0121] Furthermore, in some embodiments, the base station may configure bandwidth portions with different bandwidth sizes for the terminal for the purpose of reducing power consumption of the terminal. For example, if the terminal supports a very large bandwidth, for example, 100 MHz, and constantly transmits and receives data using that bandwidth, very large power consumption may occur. In particular, monitoring unnecessary downlink control channels using a large bandwidth of 100 MHz in a situation where there is no traffic may be very inefficient in terms of power consumption. To reduce power consumption of the terminal, the base station may configure a bandwidth portion with a relatively small bandwidth, for example, 20 MHz, for the terminal. In a situation where there is no traffic, the terminal can perform monitoring operations in the 20 MHz bandwidth portion, and when data is generated, it can transmit and receive data using the 100 MHz bandwidth portion according to the instructions of the base station.

[0122] In the method for setting the bandwidth portion, terminals prior to RRC connection (Connected) can receive configuration information for the initial bandwidth portion (Initial BWP) through the MIB during the initial access phase. More specifically, the terminal can receive a control region (i.e., CORESET) for a downlink control channel on which a DCI scheduling a System Information Block (SIB) can be transmitted from the MIB of the Physical Broadcast Channel (PBCH). The bandwidth of the control region set by the MIB can be regarded as the initial bandwidth portion, and the terminal can receive the Physical Downlink Shared Channel (PDSCH) on which the SIB is transmitted through the set initial bandwidth portion. In addition to receiving the SIB, the initial bandwidth portion can also be utilized for other system information (Other System Information (OSI), paging, and random access).

[0123] [Bandwidth Part (BWP) Change]

[0124] When one or more bandwidth part values ​​are set for a terminal, the base station can instruct the terminal to change (or switch, transition) the bandwidth part value using the bandwidth part indicator field in the DCI. For example, in FIG. 3, when the currently activated bandwidth part of the terminal is bandwidth part #1 (301), the base station can instruct the terminal to bandwidth part #2 (302) using the bandwidth part indicator in the DCI, and the terminal can perform a bandwidth part change to bandwidth part #2 (302) indicated by the bandwidth part indicator in the received DCI.

[0125] As described above, since DCI-based bandwidth part change can be indicated by DCI scheduling PDSCH or PUSCH, when a terminal receives a bandwidth part change request, it must be able to receive or transmit PDSCH or PUSCH scheduled by the corresponding DCI without difficulty in the changed bandwidth part. To this end, the standard stipulates the delay time (T) required when changing the bandwidth part. BWP ) and can be defined as in [Table 3] below, for example.

[0126] [Table 3]

[0127]

[0128] The bandwidth-partial change delay time requirement supports Type 1 or Type 2 depending on the terminal's capability. The terminal can report the supported bandwidth-partial delay time type to the base station.

[0129] According to the requirement for bandwidth part change delay time mentioned above, when the terminal receives DCI including bandwidth part change indicator in slot n, the terminal changes to the new bandwidth part indicated by the bandwidth part change indicator in slot n+T. BWP The completion can be done at a later time, and transmission and reception for the data channel scheduled by the DCI can be performed in the new bandwidth portion that has been changed. When the base station wants to schedule a data channel in the new bandwidth portion, the terminal's bandwidth portion change delay time (T BWP ), time domain resource allocation for the data channel can be determined. That is, when the base station schedules the data channel with a new bandwidth portion, the data channel can be scheduled after the bandwidth portion change delay time in the method of determining the time domain resource allocation for the data channel. Accordingly, the terminal can determine whether the DCI instructing the bandwidth portion change is after the bandwidth portion change delay time (TBWP ) may not be expected to indicate a slot offset (K0 or K2) value smaller than that.

[0130] If the terminal receives DCI (e.g., DCI format 1_1 or 0_1) indicating a bandwidth change, the terminal may not perform any transmission or reception during the time period from the third symbol of the slot in which the PDCCH including the DCI is received to the start point of the slot indicated by the slot offset (K0 or K2) value indicated by the time domain resource allocation indicator field in the DCI. For example, if the terminal receives DCI indicating a bandwidth change in slot n and the slot offset value indicated by the DCI is K, the terminal may not perform any transmission or reception from the third symbol of slot n to the symbol before slot n+K (i.e., the last symbol of slot n+K-1).

[0131] [SS / PBCH block]

[0132] Next, we will explain the SS (Synchronization Signal) / PBCH block in 5G.

[0133] An SS / PBCH block may refer to a physical layer channel block consisting of a PSS (Primary SS), SSS (Secondary SS), and PBCH. Specifically, it is as follows.

[0134] - PSS: A signal that serves as a reference for downlink time / frequency synchronization and provides some information about the cell ID.

[0135] - SSS: It serves as a reference for downlink time / frequency synchronization and provides the remaining cell ID information not provided by PSS. Additionally, it can serve as a reference signal for PBCH demodulation.

[0136] - PBCH: Provides essential system information required for transmission and reception of data and control channels of a terminal. Essential system information may include search space-related control information indicating radio resource mapping information for the control channel, and scheduling control information for a separate data channel that transmits system information.

[0137] - SS / PBCH Block: An SS / PBCH block is composed of a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks can be transmitted within a 5ms period, and each transmitted SS / PBCH block can be distinguished by an index.

[0138] The terminal can detect PSS and SSS in the initial access stage, and decode PBCH. The terminal can obtain MIB from PBCH, and can set control region (Control Resource Set; CORESET) #0 (which may correspond to a control region with a control region index of 0) therefrom. The terminal can monitor control region #0, assuming that the selected SS / PBCH block and the DMRS (Demodulation Reference Signal) transmitted in control region #0 are QCL (Quasi Co Location). The terminal can receive system information through downlink control information transmitted in control region #0. The terminal can obtain RACH (Random Access Channel) related configuration information required for initial access from the received system information. The terminal can transmit PRACH (Physical RACH) to the base station considering the selected SS / PBCH index, and the base station receiving the PRACH can obtain information on the SS / PBCH block index selected by the terminal. The base station can know that the terminal has selected a block among each SS / PBCH block and monitors the control region #0 associated with it.

[0139] [PDCCH: DCI related]

[0140] Next, we will specifically explain downlink control information (DCI) in the 5G system.

[0141] In a 5G system, scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) is transmitted from a base station to a terminal via DCI. The terminal can monitor a DCI format for fallback and a DCI format for non-fallback for the PUSCH or PDSCH. The fallback DCI format can be composed of fixed fields defined between the base station and the terminal, and the non-fallback DCI format can include configurable fields.

[0142] DCI can be transmitted through the Physical Downlink Control Channel (PDCCH) after going through the channel coding and modulation process. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC can be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs can be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly, but is included in the CRC calculation process. When the UE receives a DCI message transmitted on the PDCCH, it verifies the CRC using the assigned RNTI. If the CRC verification result is correct, the UE can determine that the message was transmitted to the UE.

[0143] For example, a DCI scheduling a PDSCH for System Information (SI) may be scrambled with SI-RNTI. A DCI scheduling a PDSCH for a Random Access Response (RAR) message may be scrambled with RA-RNTI. A DCI scheduling a PDSCH for a Paging message may be scrambled with P-RNTI. A DCI notifying a Slot Format Indicator (SFI) may be scrambled with SFI-RNTI. A DCI notifying a Transmit Power Control (TPC) may be scrambled with TPC-RNTI. A DCI scheduling a UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

[0144] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. As shown in [Table 4] below, DCI format 0_0 with the CRC scrambled with C-RNTI can include, for example, the following information.

[0145] [Table 4]

[0146]

[0147] DCI format 0_1 ​​can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_1 ​​with the CRC scrambled with C-RNTI can include, for example, the information in [Table 5] below.

[0148] [Table 5]

[0149]

[0150]

[0151] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_0 with the CRC scrambled with C-RNTI can include, for example, the information in [Table 6] below.

[0152] [Table 6]

[0153]

[0154] DCI format 1_1 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_1 with the CRC scrambled with C-RNTI can include, for example, the information in [Table 7] below.

[0155] [Table 7]

[0156]

[0157] [PDCCH: CORESET, REG, CCE, Search Space]

[0158] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0159] Below, the downlink control channel in a 5G communication system will be described in more detail with reference to drawings.

[0160] FIG. 4 is a diagram illustrating an example of a control region (control resource set, CORESET) in which a downlink control channel is transmitted in a 5G wireless communication system. FIG. 4 illustrates an example in which two control regions (control region #1 (401), control region #2 (402)) are set within a UE bandwidth part (410) in the frequency axis and within one slot (420) in the time axis. The control regions (401, 402) may be set to specific frequency resources (403) within the entire UE bandwidth part (410) in the frequency axis. The time axis may be set to one or more OFDM symbols, which may be defined as the control region length (control resource set duration, 404). Referring to the example illustrated in FIG. 4, control region #1 (401) is set to a control region length of two symbols, and control region #2 (402) is set to a control region length of one symbol.

[0161] In the aforementioned 5G, the control region can be established by the base station to the terminal via higher-layer signaling (e.g., system information, master information block (MIB), radio resource control (RRC) signaling). Establishing a control region for the terminal means providing information such as the control region identifier, the frequency location of the control region, and the symbol length of the control region. For example, as shown in [Table 8] below, the following information may be included.

[0162] [Table 8]

[0163]

[0164] In [Table 8], the tci-StatesPDCCH (simply named TCI (transmission configuration indication) state) configuration information may include information on one or more SS (synchronization signal) / PBCH (physical broadcast channel) block indices or CSI-RS (channel state information reference signal) indices that are in a QCL (quasi co-located) relationship with the DMRS transmitted in the corresponding control region.

[0165] FIG. 5A is a diagram showing an example of a basic unit of time and frequency resources that constitute a downlink control channel that can be used in 5G. According to FIG. 5A, the basic unit of time and frequency resources that constitute a control channel can be referred to as a REG (resource element group, 503), and a REG (503) can be defined as 1 OFDM symbol (501) on the time axis and 1 PRB (physical resource block, 502) on the frequency axis, i.e., 12 subcarriers. A base station can concatenate REGs (503) to constitute a downlink control channel allocation unit.

[0166] As illustrated in FIG. 5A, if the basic unit to which a downlink control channel is allocated in 5G is called a CCE (control channel element, 504), 1 CCE (504) can be composed of multiple REGs (503). Taking the REG (503) illustrated in FIG. 5A as an example, the REG (503) can be composed of 12 REs, and if 1 CCE (504) is composed of 6 REGs (503), 1 CCE (504) can be composed of 72 REs. When a downlink control region is set, the region can be composed of multiple CCEs (504), and a specific downlink control channel can be mapped to and transmitted by one or multiple CCEs (504) according to the aggregation level (AL) within the control region. CCEs (504) within the control area are distinguished by numbers, and the numbers of the CCEs (504) can be assigned according to a logical mapping method.

[0167] The basic unit of the downlink control channel illustrated in Fig. 5a, that is, the REG (503), may include both the REs to which the DCI is mapped and the areas to which the DMRS (505), which is a reference signal for decoding the REs, is mapped. As in Fig. 5a, three DMRSs (505) may be transmitted within one REG (503). The number of CCEs required to transmit the PDCCH may be 1, 2, 4, 8, or 16 depending on the aggregation level (AL), and different numbers of CCEs may be used to implement link adaptation of the downlink control channel. For example, when AL = L, one downlink control channel may be transmitted through L CCEs. The terminal must detect a signal without knowing information about the downlink control channel, and a search space representing a set of CCEs is defined for blind decoding. A search space is a set of downlink control channel candidates, consisting of CCEs that a terminal must attempt to decode at a given aggregation level. Since there are multiple aggregation levels, each of which can be a set of 1, 2, 4, 8, or 16 CCEs, a terminal can have multiple search spaces. A search space set can be defined as the set of search spaces at all configured aggregation levels.

[0168] Search spaces can be categorized into common search spaces and UE-specific search spaces. A certain group of UEs, or all UEs, can search the common search space of the PDCCH to receive cell-common control information, such as dynamic scheduling of system information or paging messages. For example, PDSCH scheduling allocation information for transmitting SIBs, including cell operator information, can be received by searching the common search space of the PDCCH. In the case of the common search space, since a certain group of UEs, or all UEs, must receive the PDCCH, it can be defined as a set of pre-arranged CCEs. UE-specific scheduling allocation information for the PDSCH or PUSCH can be received by searching the UE-specific search space of the PDCCH. The UE-specific search space can be defined UE-specifically as a function of the UE's identity and various system parameters.

[0169] In 5G, parameters for the search space for PDCCH can be configured from the base station to the terminal through higher layer signaling (e.g., SIB, MIB, RRC signaling). For example, the base station can configure the number of PDCCH candidates at each aggregation level L, the monitoring period for the search space, the monitoring occasion for each symbol within the slot for the search space, the search space type (common search space or terminal-specific search space), the combination of DCI format and RNTI to be monitored in the corresponding search space, the control region index to be monitored for the search space, etc. to the terminal. For example, the following information can be included as shown in [Table 9] below.

[0170] [Table 9]

[0171]

[0172]

[0173] Depending on the configuration information, the base station may configure one or more search space sets for the terminal. In some embodiments, the base station may configure search space set 1 and search space set 2 for the terminal, and may configure the terminal to monitor DCI format A scrambled with X-RNTI in search space set 1 in a common search space, and may configure the terminal to monitor DCI format B scrambled with Y-RNTI in search space set 2 in a terminal-specific search space.

[0174] According to the configuration information, one or more search space sets 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 configured as a common search space, and search space set #3 and search space set #4 may be configured as terminal-specific search spaces.

[0175] In the common search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these.

[0176] - 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

[0177] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0178] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0179] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

[0180] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0181] In a terminal-specific search space, the following combinations of DCI formats and RNTIs can be monitored. Of course, the examples below are not limited to these examples.

[0182] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0183] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

[0184] The RNTIs specified may follow the definitions and uses below.

[0185] - C-RNTI (Cell RNTI): For terminal-specific PDSCH scheduling purposes.

[0186] - TC-RNTI (Temporary Cell RNTI): For terminal-specific PDSCH scheduling purposes.

[0187] - CS-RNTI (Configured Scheduling RNTI): Used for terminal-specific PDSCH scheduling that is set semi-statically.

[0188] - RA-RNTI (Random Access RNTI): Used for PDSCH scheduling in the random access phase.

[0189] - P-RNTI (Paging RNTI): Used for scheduling PDSCH where paging is transmitted.

[0190] - SI-RNTI (System Information RNTI): Used for scheduling PDSCH where system information is transmitted.

[0191] - INT-RNTI (Interruption RNTI): Used to indicate whether pucturing is in progress for PDSCH.

[0192] - TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Used to indicate power control commands for PUSCH.

[0193] - TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to indicate power control commands for PUCCH.

[0194] - TPC-SRS-RNTI (Transmit Power Control for SRS RNTI): Used to indicate power control commands for SRS.

[0195] The aforementioned specified DCI formats may follow the definitions in [Table 10] below.

[0196] [Table 10]

[0197]

[0198] In 5G, the search space of aggregation level L in the control region p and search space set s can be expressed as in the following mathematical expression 1.

[0199] [Mathematical Formula 1]

[0200]

[0201] - : Integration level

[0202] - : Carrier Index

[0203] - : Total number of CCEs existing within the control region p

[0204] - : slot index

[0205] - : Number of PDCCH candidates for aggregation level L

[0206] - : PDCCH candidate index of aggregation level L

[0207] -

[0208] - , , , , ,

[0209] - : Terminal identifier

[0210] The value can be 0 for a common search space.

[0211] In the case of a terminal-specific search space, the value may correspond to a value that changes depending on the terminal's identity (C-RNTI or ID set to the terminal by the base station) and the time index.

[0212] In 5G, since multiple search space sets can be configured with different parameters (e.g., parameters in [Table 9]), the set of search space sets monitored by a terminal at each point in time can be different. For example, if search space set #1 is configured with an X-slot period and search space set #2 is configured with a Y-slot period and X and Y are different, the terminal can monitor both search space set #1 and search space set #2 in a specific slot, or can monitor either search space set #1 or search space set #2 in a specific slot.

[0213] [PDCCH: span]

[0214] A terminal can perform terminal capability reporting for each subcarrier interval when it has multiple PDCCH monitoring positions within a slot, and at this time, the concept of Span can be used. A Span refers to consecutive symbols within a slot in which the terminal can monitor a PDCCH, and each PDCCH monitoring position is within one Span. A Span can be expressed as (X, Y), where x refers to the minimum number of symbols that must be spaced between the first symbols of two consecutive Spans, and Y refers to the number of consecutive symbols in which the PDCCH can be monitored within one Span. In this case, the terminal can monitor the PDCCH in the section from the first symbol of the Span to within Y symbols within the Span.

[0215] FIG. 5b is a diagram illustrating a case in which a terminal in a wireless communication system can have multiple PDCCH monitoring positions within a slot, using Span. For example, Span can be (X,Y) = (7,4), (4,3), (2,2), and each of the three cases is represented by (5b-00), (5b-05), and (5b-10) in FIG. 5b. For example, (5b-00) represents a case in which two Spans, which can be represented as (7,4), exist within a slot. The interval between the first symbols of the two Spans is represented as X=7, and PDCCH monitoring positions can exist within a total of Y=3 symbols from the first symbol of each Span, and it is shown that search spaces 1 and 2 each exist within Y=3 symbols. As another example, (5b-05) represents a case where there are a total of three Spans in the slot that can be expressed as (4,3), and the gap between the second and third Spans is shown to be X'=5 symbols, which is greater than X=4.

[0216] [PDCCH: Terminal Capability Report]

[0217] The slot locations where the above-described common search space and terminal-specific search space are located are indicated by the monitoringSymbolsWitninSlot parameter in [Table 9], and the symbol locations within the slot are indicated as a bitmap through the monitoringSymbolsWithinSlot parameter in [Table 9]. Meanwhile, the symbol locations within the slot where the terminal can monitor the search space can be reported to the base station through the following terminal capabilities (UE capabilities).

[0218] - Terminal capability 1 (hereinafter referred to as FG 3-1). This terminal capability refers to the capability to monitor a monitoring occasion (MO) for a Type 1 and Type 3 common search space or a terminal-specific search space when the MO location is located within the first three symbols of the slot, as shown in [Table 11] below. This terminal capability is a mandatory capability that all terminals supporting NR must support, and whether or not this capability is supported is not explicitly reported to the base station.

[0219] [Table 11]

[0220]

[0221] - Terminal Capability 2 (hereinafter referred to as FG 3-2). This terminal capability refers to the capability to monitor a common search space or a terminal-specific search space, regardless of the starting symbol position of a monitoring occasion (MO), if there is one within a slot, as shown in [Table 12] below. This terminal capability is optional for the terminal, and whether or not it is supported can be explicitly reported to the base station.

[0222] [Table 12]

[0223]

[0224] - Terminal capability 3 (hereinafter referred to as FG 3-5, 3-5a, 3-5b). This terminal capability indicates the pattern of MOs that the terminal can monitor when there are multiple monitoring positions (MOs: monitoring occasions) for a common search space or a terminal-specific search space within a slot, as shown in the following [Table 13]. The above-described pattern is composed of the start symbol interval X between different MOs and the maximum symbol length Y for one MO. The combination of (X, Y) supported by the terminal can be one or more of {(2,2), (4,3), (7,3)}. This terminal capability can be selectively supported by the terminal (optional), and whether this capability is supported and the above-described combination of (X, Y) can be explicitly reported to the base station.

[0225] [Table 13]

[0226]

[0227]

[0228] The terminal may report to the base station whether it supports the aforementioned terminal capabilities 2 and / or 3 and related parameters. Based on the reported terminal capabilities, the base station may perform time-domain resource allocation for the common search space and terminal-specific search space. When allocating these resources, the base station may ensure that the MO is not positioned in a location that the terminal cannot monitor.

[0229] [DRX]

[0230] Figure 6 is a diagram for explaining DRX (discontinuous reception).

[0231] DRX (discontinuous reception) is an operation in which a terminal using a service discontinuously receives data while in an RRC connected state, where a radio link is established between the base station and the terminal. When DRX is applied, the terminal turns on the receiver at a specific time to monitor the control channel, and if no data is received for a certain period of time, the receiver is turned off, thereby reducing the terminal's power consumption. DRX operation can be controlled by the MAC layer device based on various parameters and timers.

[0232] Referring to FIG. 6, the active time (605) is the time during which the terminal wakes up every DRX cycle and monitors the PDCCH. The active time (605) can be defined as follows.

[0233] - drx-onDurationTimer or drx-InactivityTimer or drx-RetransmissionTimerDL or drx-RetransmissionTimerUL or ra-ContentionResolutionTimer is running; or

[0234] - a Scheduling Request is sent on PUCCH and is pending; or

[0235] - a PDCCH indicating a new transmission addressed to the C-RNTI of the MAC entity has not been received after successful reception of a Random Access Response for the Random Access Preamble not selected by the MAC entity among the contention-based Random Access Preamble

[0236] drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, drx-RetransmissionTimerUL, ra-ContentionResolutionTimer, etc. are timers whose values ​​are set by the base station, and have the function of setting the terminal to monitor the PDCCH when a certain condition is met.

[0237] drx-onDurationTimer (615) is a parameter for setting the minimum time for which the terminal stays awake in the DRX cycle. drx-InactivityTimer (620) is a parameter for setting the additional time for which the terminal stays awake when receiving (630) a PDCCH indicating a new uplink transmission or downlink transmission. drx-RetransmissionTimerDL is a parameter for setting the maximum time for which the terminal stays awake to receive a downlink retransmission in the downlink HARQ procedure. drx-RetransmissionTimerUL is a parameter for setting the maximum time for which the terminal stays awake to receive an uplink retransmission grant in the uplink HARQ procedure. drx-onDurationTimer, drx-InactivityTimer, drx-RetransmissionTimerDL, and drx-RetransmissionTimerUL can be set to, for example, time, the number of subframes, the number of slots, etc. ra-ContentionResolutionTimer is a parameter for monitoring PDCCH in random access procedure.

[0238] The inactive time (610) is a time set not to monitor PDCCH during DRX operation and / or a time set not to receive PDCCH. The remaining time excluding the active time (605) from the entire time of performing DRX operation can be the inactive time (610). If the terminal does not monitor PDCCH during the active time (605), it can enter a sleep or inactive state to reduce power consumption.

[0239] DRX cycle refers to the period during which the terminal wakes up and monitors the PDCCH. In other words, it refers to the time interval or on duration that occurs after the terminal monitors the PDCCH until it monitors the next PDCCH. DRX cycles are divided into two types: short DRX cycle and long DRX cycle. The short DRX cycle can be applied optionally.

[0240] Long DRX cycle (625) is the longer cycle among the two DRX cycles set in the terminal. While operating in Long DRX, the terminal starts drx-onDurationTimer (615) again at a point in time when Long DRX cycle (625) has elapsed from the starting point (e.g., start symbol) of drx-onDurationTimer (615). When operating in Long DRX cycle (625), the terminal can start drx-onDurationTimer (615) in a slot after drx-SlotOffset in a subframe satisfying Mathematical Formula 2 below. Here, drx-SlotOffset means a delay before starting drx-onDurationTimer (615). drx-SlotOffset can be set to, for example, time, the number of slots, etc.

[0241] [Equation 2]

[0242] [(SFN

[0243] At this time, drx-LongCycleStartOffset can be used to define the Long DRX cycle (625) and drx-StartOffset can be used to define the subframe at which the Long DRX cycle (625) will start. drx-LongCycleStartOffset can be set to, for example, time, number of subframes, number of slots, etc.

[0244] [PDCCH: BD / CCE limit]

[0245] When multiple search space sets are set for a terminal, the following conditions may be considered in determining the search space set that the terminal should monitor.

[0246] If the value of monitoringCapabilityConfig-r16, which is an upper layer signaling, is set to r15monitoringcapability, the terminal defines the maximum values ​​for the number of PDCCH candidates that can be monitored and the number of CCEs that constitute the entire search space (wherein the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) per slot, and if the value of monitoringCapabilityConfig-r16 is set to r16monitoringcapability, the terminal defines the maximum values ​​for the number of PDCCH candidates that can be monitored and the number of CCEs that constitute the entire search space (wherein the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) per Span.

[0247] [Condition 1: Limit the maximum number of PDCCH candidates]

[0248] As described above, depending on the setting value of the upper layer signaling, the maximum number of PDCCH candidates that the terminal can monitor, Mμ, can follow [Table 14] below when defined on a slot basis in a cell set to a subcarrier spacing of 15·2μ kHz, and can follow [Table 15] below when defined on a span basis.

[0249] [Table 14]

[0250]

[0251] [Table 15]

[0252]

[0253] [Condition 2: Maximum CCE limit]

[0254] As above, according to the setting value of the upper layer signaling, the maximum number of CCEs that constitute the entire search space (here, the entire search space means the entire set of CCEs corresponding to the union area of ​​multiple search space sets) is C μ is a subcarrier spacing of 15·2 μ When defined based on slot in a cell set to kHz, it can follow [Table 16] below, and when defined based on span, it can follow [Table 17] below.

[0255] [Table 16]

[0256]

[0257] [Table 17]

[0258]

[0259] For convenience of explanation, let us define a situation where both conditions 1 and 2 are satisfied at a certain point in time as "Condition A." Therefore, not satisfying Condition A may mean not satisfying at least one of conditions 1 and 2.

[0260] [PDCCH: Overbooking]

[0261] Depending on the configuration of the search space sets of the base station, there may be cases where condition A is not satisfied at a certain point in time. If condition A is not satisfied at a certain point in time, the terminal can select and monitor only some of the search space sets configured to satisfy condition A at that point in time, and the base station can transmit a PDCCH to the selected search space set.

[0262] The following method can be followed to select a partial search space from the entire set of search spaces.

[0263] If condition A for PDCCH is not satisfied at a specific point in time (slot), the terminal (or base station) may preferentially select a search space set whose search space type is set to a common search space from among the search space sets existing at that point in time over a search space set whose search space type is set to a terminal-specific search space.

[0264] If all search space sets set as common search spaces are selected (i.e., if condition A is satisfied even after selecting all search spaces set as common search spaces), the terminal (or base station) can select search space sets set as terminal-specific search spaces. In this case, if there are multiple search space sets set as terminal-specific search spaces, a search space set with a lower search space set index may have a higher priority. Considering the priority, terminal-specific search space sets can be selected within the range where condition A is satisfied.

[0265] [QCL, TCI state]

[0266] In a wireless communication system, one or more different antenna ports (or one or more channels, signals, and combinations thereof, but for convenience, they will be referred to as different antenna ports in the following description of the present disclosure) can be associated with each other by QCL (Quasi co-location) settings as shown in [Table 18] below. The TCI state is to notify the QCL relationship between the PDCCH (or PDCCH DMRS) and other RSs or channels. When a reference antenna port A (reference RS #A) and another target antenna port B (target RS #B) are QCLed with each other, it means that the terminal is allowed to apply some or all of the large-scale channel parameters estimated at the antenna port A to the channel measurement from the antenna port B. QCL may need to relate different parameters depending on the situation, such as 1) time tracking affected by average delay and delay spread, 2) frequency tracking affected by Doppler shift and Doppler spread, 3) radio resource management (RRM) affected by average gain, and 4) beam management (BM) affected by spatial parameters. Accordingly, NR supports four types of QCL relationships, as shown in [Table 18] below.

[0267] [Table 18]

[0268]

[0269] The above spatial RX parameter may collectively refer to some or all of various parameters, such as angle of arrival (AoA), power angular spectrum (PAS) of AoA, angle of departure (AoD), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, and spatial channel correlation.

[0270] The above QCL relationship can be set to the terminal through the RRC parameters TCI-State and QCL-Info as shown in [Table 19] below. Referring to [Table 19], the base station can set one or more TCI states to the terminal and inform the RS referencing the ID of the TCI state, i.e., up to two QCL relationships (qcl-Type1, qcl-Type2) for the target RS. At this time, each QCL information (QCL-Info) included in the above TCI state includes the serving cell index and BWP index of the reference RS indicated by the corresponding QCL information, the type and ID of the reference RS, and the QCL type as shown in [Table 18] above.

[0271] [Table 19]

[0272]

[0273] FIG. 7 is a diagram illustrating an example of base station beam allocation according to TCI state settings. Referring to FIG. 7, the base station can transmit information on N different beams to the terminal through N different TCI states. For example, in case of N=3 as shown in FIG. 7, the base station can set the qcl-Type2 parameter included in three TCI states (700, 705, 710) to be associated with CSI-RS or SSB (synchronization signal block) corresponding to different beams and to QCL type D, thereby notifying that antenna ports referencing different TCI states 700, 705, or 710 are associated with different spatial Rx parameters, i.e., different beams.

[0274] Tables 20 to 24 below show valid TCI state settings according to target antenna port type.

[0275] [Table 20] shows valid TCI state settings when the target antenna port is a CSI-RS for tracking (TRS). The TRS refers to an NZP CSI-RS in which the repetition parameter is not set and trs-Info is set to true among CSI-RSs. Setting 3 in [Table 20] can be used for aperiodic TRS.

[0276] [Table 20] Valid TCI state settings when the target antenna port is CSI-RS for tracking (TRS)

[0277]

[0278] [Table 21] shows valid TCI state settings when the target antenna port is a CSI-RS for CSI. The CSI-RS for CSI refers to an NZP CSI-RS in which a parameter indicating repetition (e.g., repetition parameter) among CSI-RSs is not set and trs-Info is not set to true.

[0279] [Table 21] Valid TCI state settings when the target antenna port is CSI-RS for CSI

[0280]

[0281] [Table 22] shows the valid TCI state settings when the target antenna port is CSI-RS for beam management (BM, which has the same meaning as CSI-RS for L1 RSRP reporting). The CSI-RS for BM refers to an NZP CSI-RS in which the repetition parameter is set to On or Off among CSI-RSs and trs-Info is not set to true.

[0282] [Table 22] Valid TCI state settings when the target antenna port is CSI-RS for BM (for L1 RSRP reporting)

[0283]

[0284] [Table 23] shows the valid TCI state settings when the target antenna port is PDCCH DMRS.

[0285] [Table 23] Valid TCI state settings when the target antenna port is PDCCH DMRS

[0286]

[0287] [Table 24] shows the valid TCI state settings when the target antenna port is PDSCH DMRS.

[0288] [Table 24] Valid TCI state settings when the target antenna port is PDSCH DMRS

[0289]

[0290] A representative QCL setting method according to the above [Table 20] to [Table 24] is to set and operate the target antenna port and reference antenna port for each step as "SSB" -> "TRS" -> "CSI-RS for CSI, or CSI-RS for BM, or PDCCH DMRS, or PDSCH DMRS." Through this, it is possible to link statistical characteristics that can be measured from SSB and TRS to each antenna port to assist the terminal's receiving operation.

[0291] [PDCCH: TCI state related]

[0292] Specifically, the TCI state combinations applicable to the PDCCH DMRS antenna port are as shown in [Table 25] below. The fourth row in [Table 25] is the combination assumed by the terminal before RRC configuration, and configuration after RRC is not possible.

[0293] [Table 25]

[0294]

[0295] NR supports a hierarchical signaling method as illustrated in FIG. 8 for dynamic allocation of PDCCH beams. Referring to FIG. 8, a base station can set N TCI states (805, 810, ..., 820) to a terminal via RRC signaling (800), and can set some of them as TCI states for CORESET (825). Thereafter, the base station can indicate one of the TCI states (830, 835, 840) for CORESET to the terminal via MAC CE signaling (845). Thereafter, the terminal can receive the PDCCH based on beam information included in the TCI state indicated by the MAC CE signaling.

[0296] FIG. 9 is a diagram illustrating a TCI indication MAC CE signaling structure for the PDCCH DMRS.

[0297] Referring to FIG. 9, the TCI indication MAC CE signaling for the PDCCH DMRS may consist of 2 bytes (16 bits) and may include a 5-bit serving cell ID (915), a 4-bit CORESET ID (920), and a 7-bit TCI state ID (925).

[0298] FIG. 10 is a diagram illustrating an example of beam setting of a control resource set (CORESET) and a search space according to the above description.

[0299] Referring to FIG. 10, the base station can indicate one of the TCI state lists included in the CORESET (1000) configuration through MAC CE signaling (1005). Until another TCI state is indicated to the corresponding CORESET through another MAC CE signaling, the terminal considers that the same QCL information (beam #1, 1005) is applied to all search spaces (1010, 1015, 1020) connected to the CORESET. The PDCCH beam allocation method described above has a problem in that it is difficult to indicate a beam change faster than the MAC CE signaling delay, and also has a disadvantage in that the same beam is applied to each CORESET regardless of the search space characteristics, which makes flexible PDCCH beam operation difficult.

[0300] The embodiments of the present disclosure below provide more flexible PDCCH beam configuration and operation methods. While several distinct examples are provided for convenience in describing the embodiments of the present disclosure below, they are not mutually exclusive and can be applied in appropriate combinations depending on the situation.

[0301] A base station can set one or more TCI states for a specific control region to a terminal, and can activate one of the set TCI states through a MAC CE activation command. For example, if {TCI state#0, TCI state#1, TCI state#2} are set as TCI states in control region #1, the base station can transmit a command to the terminal to activate TCI state#0 for control region #1 through MAC CE. Based on the activation command for the TCI state received through MAC CE, the terminal can correctly receive DMRS of the corresponding control region based on QCL information in the activated TCI state.

[0302] For a control region (control region #0) with an index set to 0, if the terminal has not received a MAC CE activation command for the TCI state of control region #0, the terminal can assume that the SS / PBCH block identified during the initial access process or the non-contention-based random access process that is not triggered by a PDCCH command for the DMRS transmitted in control region #0 is QCL.

[0303] For a control region (control region #X) whose index is set to a value other than 0, if the terminal has not set a TCI state for the control region #X, or has set one or more TCI states but has not received a MAC CE activation command to activate one of them, the terminal may assume that the DMRS transmitted in the control region #X is QCL with the SS / PBCH block identified during the initial access process.

[0304] [PDCCH: QCL prioritization rule related]

[0305] Below, the QCL priority determination operation for PDCCH is described in detail.

[0306] When a terminal operates with carrier aggregation within a single cell or band, and multiple CORESETs within an activated bandwidth portion of a single or multiple subcarriers have the same or different QCL-TypeD characteristics and overlap in time during a specific PDCCH monitoring interval, the terminal may select a specific CORESET according to a QCL priority determination operation and monitor CORESETs that have the same QCL-TypeD characteristics as the selected CORESET. That is, when multiple CORESETs overlap in time, only one QCL-TypeD characteristic can be received. In this case, the criteria for determining the QCL priority may be as follows.

[0307] - Criterion 1. CORESET connected to the common search space of the lowest index among the subcarriers corresponding to the lowest index among the subcarriers containing the common search space.

[0308] - Criterion 2. CORESET connected to the terminal-specific search space of the lowest index among the subcarriers corresponding to the lowest index among the subcarriers containing the terminal-specific search space.

[0309] As described above, if the above criteria are not met, the following criteria are applied. For example, if CORESETs overlap in time in a specific PDCCH monitoring interval, and if not all CORESETs are connected to a common search space but to a terminal-specific search space, i.e., if Criterion 1 is not met, the terminal may skip applying Criterion 1 and apply Criterion 2.

[0310] When a terminal selects a CORESET based on the above-described criteria, the terminal may additionally consider the following two items regarding the QCL information set in the CORESET. First, if a first CORESET has a first CSI-RS as a reference signal having a QCL-TypeD relationship, and the reference signal of this first CSI-RS having a QCL-TypeD relationship is the first SSB, and another second CORESET has a reference signal having a QCL-TypeD relationship that is the first SSB, the terminal may consider that the first and second CORESETs have different QCL-TypeD characteristics. Second, if the first CORESET has a first CSI-RS set on the first subcarrier as a reference signal having a QCL-TypeD relationship, and the reference signal of the first CSI-RS having a QCL-TypeD relationship is the first SSB, and the second CORESET has a second CSI-RS set on the second subcarrier as a reference signal having a QCL-TypeD relationship, and the reference signal of the second CSI-RS having a QCL-TypeD relationship is the same first SSB, the terminal may consider the two CORESETs to have the same QCL-TypeD characteristic.

[0311] FIG. 12a and FIG. 12b are diagrams for explaining a method for selecting a receivable CORESET by considering priority when a terminal receives a downlink control channel in a wireless communication system according to one embodiment of the present disclosure.

[0312] For example, a terminal may be configured to receive multiple CORESETs that overlap in time in a specific PDCCH monitoring period (1210), and these multiple CORESETs may be connected to a common search space (CSS) or a UE-specific search space (USS) for multiple cells.

[0313] Within the corresponding PDCCH monitoring section (1210), there may be a CORESET (1215) connected to the common search space (1) within the bandwidth portion (1200) of the cell (or component carrier, CC#1) (1200), and there may be a CORESET (1220) connected to the common search space (1) within the bandwidth portion (1205) of the cell (or CC#2) (1205) and a CORESET (1225) connected to the terminal-specific search space (2).

[0314] CORESET (1215) and CORESET (1220) may have a relationship with the 1st CSI-RS resource set within the 1st bandwidth portion of the 1st cell and QCL-TypeD, and CORESET (1225) may have a relationship with the 1st CSI-RS resource set within the 1st bandwidth portion of the 2nd cell and QCL-TypeD. Therefore, if criterion 1 is applied to the corresponding PDCCH monitoring period (1210), all other CORESETs having the same QCL-TypeD reference signal as CORESET (1215) can be received. Therefore, the terminal can receive CORESET (1215) and CORESET (1220) in the corresponding PDCCH monitoring period (1210).

[0315] As another example, a terminal may be configured to receive multiple CORESETs that overlap in time in a specific PDCCH monitoring interval (1240), and these multiple CORESETs may be associated with a common search space or a terminal-specific search space for multiple cells.

[0316] Within the corresponding PDCCH monitoring section (1240), within the bandwidth portion (1230) of the cell (or CC#1), there may exist a CORESET (1245) connected to the terminal-specific search space (1) and a CORESET (1250) connected to the terminal-specific search space (2), and within the bandwidth portion (1235) of the cell (or CC#2), there may exist a CORESET (1255) connected to the terminal-specific search space (1) and a CORESET (1260) connected to the terminal-specific search space (3).

[0317] CORESET (1245) and CORESET (1250) have a relationship with the 1st CSI-RS resource set in the 1st bandwidth part of the 1st cell and QCL-TypeD, CORESET (1255) has a relationship with the 1st CSI-RS resource set in the 1st bandwidth part of the 2nd cell and QCL-TypeD, and CORESET (1260) can have a relationship with the 2nd CSI-RS resource set in the 1st bandwidth part of the 2nd cell and QCL-TypeD. If criterion 1 is applied to the corresponding PDCCH monitoring section (1240), there is no common search space, so the next criterion, criterion 2, can be applied. If criterion 2 is applied to the corresponding PDCCH monitoring section (1240), all other CORESETs having the same QCL-TypeD reference signal as CORESET (1245) can be received. Accordingly, the terminal can receive CORESET (1245) and CORESET (1250) in the corresponding PDCCH monitoring section (1240).

[0318] [Rate matching / Puncturing related]

[0319] Below, the rate matching operation and puncturing operation are described in detail.

[0320] When a time and frequency resource A, through which an arbitrary symbol sequence A is to be transmitted, overlaps with an arbitrary time and frequency resource B, a rate matching or puncturing operation may be considered for transmission and reception operations of channel A considering resource C, an area in which resources A and B overlap. The specific operations may follow the contents below.

[0321] Rate Matching Operation

[0322] The base station can map and transmit channel A only for the remaining resource areas excluding resource C corresponding to the overlapping area with resource B among the entire resources A that want to transmit symbol sequence A to the terminal. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the base station can sequentially map and transmit symbol sequence A to {resource #1, resource #2, resource #4}, which are the remaining resources among resource A excluding {resource #3} corresponding to resource C. As a result, the base station can map and transmit symbol sequences {symbol #1, symbol #2, symbol #3} to {resource #1, resource #2, resource #4}, respectively.

[0323] The terminal can determine resources A and B from scheduling information for symbol sequence A from the base station, and can thereby determine resource C, which is an area where resources A and B overlap. The terminal can receive symbol sequence A, assuming that symbol sequence A was mapped and transmitted in the remaining area of ​​the entire resource A except for resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, and resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the terminal can receive symbol sequence A, assuming that it was sequentially mapped to {resource #1, resource #2, resource #4}, which are the remaining resources among resource A except for {resource #3}, which corresponds to resource C. As a result, the terminal can perform a series of subsequent reception operations, assuming that symbol sequences {symbol #1, symbol #2, symbol #3} were mapped and transmitted to {resource #1, resource #2, resource #4}, respectively.

[0324] Puncture action

[0325] If a base station wants to transmit symbol sequence A to a terminal, and there is a resource C corresponding to an area overlapping with resource B among all resources A, the base station maps symbol sequence A to the entire resource A, but does not perform transmission in the resource area corresponding to resource C, and can perform transmission only for the remaining resource areas of resource A excluding resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the base station can map symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} to resource A {resource #1, resource #2, resource #3, resource #4}, and transmit only the symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to the remaining resources {resource #1, resource #2, resource #4} excluding {resource #3} corresponding to resource C among resources A, and may not transmit {symbol #3} mapped to {resource #3} corresponding to resource C. As a result, the base station can transmit symbol sequences {symbol #1, symbol #2, symbol #4} by mapping them to {resource #1, resource #2, resource #4}, respectively.

[0326] The terminal can determine resources A and B from scheduling information for symbol sequence A from the base station, and can thereby determine resource C, which is an area where resources A and B overlap. The terminal can receive symbol sequence A assuming that symbol sequence A is mapped to the entire resource A, but is transmitted only in the remaining area of ​​resource area A excluding resource C. For example, if symbol sequence A is composed of {symbol #1, symbol #2, symbol #3, symbol #4}, resource A is {resource #1, resource #2, resource #3, resource #4}, and resource B is {resource #3, resource #5}, the terminal can assume that symbol sequence A {symbol #1, symbol #2, symbol #3, symbol #4} is mapped to resource A {resource #1, resource #2, resource #3, resource #4} respectively, but {symbol #3} mapped to {resource #3} corresponding to resource C is not transmitted, and can receive it assuming that symbol sequence {symbol #1, symbol #2, symbol #4} corresponding to {resource #1, resource #2, resource #4}, which are the remaining resources among resource A except {resource #3} corresponding to resource C, are mapped and transmitted. As a result, the terminal can assume that the symbol sequence {symbol #1, symbol #2, symbol #4} is transmitted by being mapped to {resource #1, resource #2, resource #4}, respectively, and perform a series of subsequent receiving operations.

[0327] Below, we describe a method for configuring rate-matching resources for the purpose of rate-matching in 5G communication systems. Rate-matching refers to adjusting the size of a signal based on the amount of resources available for transmission. For example, rate-matching a data channel may mean adjusting the size of data accordingly, without mapping the data channel to a specific time and frequency resource region.

[0328] Figure 11 is a diagram for explaining a method in which a base station and a terminal transmit and receive data by considering downlink data channels and rate matching resources.

[0329] FIG. 11 illustrates a downlink data channel (PDSCH, 1101) and a rate matching resource (1102). A base station can configure one or more rate matching resources (1102) to a terminal through upper layer signaling (e.g., RRC signaling). The rate matching resource (1102) configuration information can include time-domain resource allocation information (1103), frequency-domain resource allocation information (1104), and period information (1105). In the following, the bitmap corresponding to the frequency-domain resource allocation information (1104) is named "the first bitmap", the bitmap corresponding to the time-domain resource allocation information (1103) is named "the second bitmap", and the bitmap corresponding to the period information (1105) is named "the third bitmap". When all or part of the time and frequency resources of a scheduled data channel (1101) overlap with the set rate matching resources (602), the base station can rate-match and transmit the data channel (1101) in the rate matching resource (1102) portion, and the terminal can perform reception and decoding after assuming that the data channel (1101) is rate-matched in the rate matching resource (1102) portion.

[0330] The base station can dynamically notify the terminal via DCI whether to rate-match the data channel in the set rate-matching resource portion through additional configuration (corresponding to the "rate-matching indicator" in the aforementioned DCI format). Specifically, the base station can select some of the set rate-matching resources and group them into rate-matching resource groups, and can use a bitmap to indicate to the terminal via DCI whether the data channel for each rate-matching resource group is rate-matched. For example, if four rate-matching resources, RMR#1, RMR#2, RMR#3, and RMR#4, are set, the base station can set RMG#1={RMR#1, RMR#2}, RMG#2={RMR#3, RMR#4} as the rate-matching groups, and can use two bits in the DCI field to indicate to the terminal whether to rate-match in RMG#1 and RMG#2, respectively, using a bitmap. For example, if rate matching is required, it can be indicated as "1", and if rate matching is not required, it can be indicated as "0".

[0331] 5G supports granularity at the "RB symbol level" and "RE level" by setting the aforementioned rate matching resources on the terminal. More specifically, the following setting method can be followed.

[0332] RB symbol level

[0333] A terminal can receive up to four RateMatchPatterns for each bandwidth section through upper layer signaling, and one RateMatchPattern can include the following contents.

[0334] - As a reserved resource within the bandwidth section, a resource in which the time and frequency resource domains of the reserved resource are set by combining a bitmap at the RB level and a bitmap at the symbol level along the frequency axis may be included. The reserved resource may span one or two slots. A time domain pattern (periodicityAndPattern) in which the time and frequency domains composed of each RB level and symbol level bitmap pair are repeated may additionally be set.

[0335] - The bandwidth section may include a time and frequency domain resource area set as CORESET and a resource area corresponding to a time domain pattern set as a search space setting in which the resource area is repeated.

[0336] RE level

[0337] The terminal can be configured with the following contents through upper layer signaling.

[0338] - The configuration information (lte-CRS-ToMatchAround) for RE corresponding to the LTE CRS (cell-specific reference signal or common reference signal) pattern may include the number of ports (nrofCRS-Ports) of LTE CRS and the LTE-CRS-vshift(s) value (v-shift), the location information (carrierFreqDL) of the center subcarrier of the LTE carrier from the reference frequency point (e.g., reference point A), the bandwidth size (carrierBandwidthDL) information of the LTE carrier, and the subframe configuration information (mbsfn-SubframConfigList) corresponding to the MBSFN (Multicast-broadcast single-frequency network). Based on the above-described information, the terminal may determine the location of the CRS within the NR slot corresponding to the LTE subframe.

[0339] - It may include configuration information for a set of resources corresponding to one or more ZP (zero power) CSI-RSs within the bandwidth section.

[0340] [Regarding terminal capability reporting]

[0341] In LTE and NR, a terminal, while connected to a serving base station, can perform a procedure to report its supported capabilities to the base station. In the description below, this is referred to as a UE capability report.

[0342] A base station can transmit a UE capability inquiry message requesting a capability report to a connected terminal. The message can include a UE capability request for each RAT (radio access technology) type of the base station. The RAT type-specific request can include information on a combination of supported frequency bands, etc. In addition, in the case of the UE capability inquiry message, UE capabilities for multiple RAT types can be requested through a single RRC message container transmitted by the base station, or the base station can include multiple UE capability inquiry messages including UE capability requests for each RAT type and transmit them to the terminal. That is, the UE capability inquiry can be repeated multiple times in one message, and the terminal can compose a corresponding UE capability information message and report it multiple times. In the next-generation mobile communication system, a UE capability request can be made for MR-DC (Multi-RAT dual connectivity), including NR, LTE, and EN-DC (E-UTRA - NR dual connectivity). Additionally, the terminal capability inquiry message is typically transmitted initially after the terminal is connected to the base station, but the base station may request it under any conditions when necessary.

[0343] In the above step, a terminal that receives a UE capability report request from a base station can configure terminal capability based on the RAT type and band information requested from the base station. Below, we summarize how a terminal configures UE capability in an NR system.

[0344] 1. If the UE receives a list of LTE and / or NR bands through a UE capability request from the base station, the UE can configure a band combination (BC) for EN-DC and NR stand-alone (SA). That is, a candidate list of BCs for EN-DC and NR SA can be configured based on the bands requested to the base station via FreqBandList. In addition, the band priorities can be prioritized in the order listed in FreqBandList.

[0345] 2. If the base station requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the UE completely removes NR SA BCs from the list of configured BC candidates. This operation can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0346] 3. Afterwards, the terminal can remove fallback BCs from the BC candidate list constructed in the above step. Here, a fallback BC refers to a BC obtained by removing at least one band corresponding to an SCell from a random BC. Since the BC before removing the band corresponding to at least one SCell can already cover the fallback BC, this step can be omitted. This step can also be applied to MR-DC, i.e., to LTE bands. The BCs remaining after this step are the final "candidate BC list."

[0347] 4. The terminal can select BCs to report by selecting BCs that match the requested RAT type from the final "candidate BC list" above. In this step, the terminal constructs the supportedBandCombinationList in a set order. That is, the terminal constructs BCs and UE capabilities to report according to the preset rat-Type order (nr -> eutra-nr -> eutra). In addition, it constructs a featureSetCombination for the constructed supportedBandCombinationList, and constructs a list of "candidate feature set combinations" from the candidate BC list after removing the list for the fallback BC (which contains capabilities of the same or lower level). The "candidate feature set combinations" above include feature set combinations for both NR and EUTRA-NR BCs, and can be obtained from the feature set combinations of the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0348] 5. Also, if the requested rat Type is eutra-nr and has influence, featureSetCombinations are included in both containers: UE-MRDC-Capabilities and UE-NR-Capabilities. However, the feature set of NR can only be included in UE-NR-Capabilities.

[0349] After terminal capabilities are configured, the terminal transmits a terminal capability information message containing the terminal capabilities to the base station. Based on the terminal capabilities received from the terminal, the base station then performs appropriate scheduling and transmission / reception management for the terminal.

[0350] [CA / DC related]

[0351] FIG. 13 is a diagram illustrating a wireless protocol structure of a base station and a terminal in a single cell, carrier aggregation, and dual connectivity situation according to one embodiment of the present disclosure.

[0352] Referring to FIG. 13, the wireless protocol of the next-generation mobile communication system is composed of NR SDAP (service data adaptation protocol S25, S70), NR PDCP (packet data convergence protocol S30, S65), NR RLC (radio link control S35, S60), and NR MAC (medium access control S40, S55) in the terminal and NR base station, respectively.

[0353] Key features of NR SDAP (S25, S70) may include some of the following:

[0354] - Transfer of user plane data

[0355] - Mapping function between QoS flow and data bearer for both DL and UL

[0356] - Marking function of QoS flow ID for both uplink and downlink (marking QoS flow ID in both DL and UL packets)

[0357] - Ability to map reflective QoS flow to data bearer for uplink SDAP PDUs (reflective QoS flow to DRB mapping for the UL SDAP PDUs).

[0358] For the above SDAP layer device, the terminal can be configured by RRC message for each PDCP layer device, each bearer, or each logical channel, whether to use the header of the SDAP layer device or whether to use the function of the SDAP layer device, and when the SDAP header is configured, the terminal can instruct the NAS QoS reflection configuration 1-bit indicator (NAS reflective QoS) and the AS QoS reflection configuration 1-bit indicator (AS reflective QoS) of the SDAP header to update or reset the mapping information for the QoS flow and data bearer of the uplink and downlink. The SDAP header can include QoS flow ID information indicating QoS. The QoS information can be used as data processing priority, scheduling information, etc. to support a smooth service.

[0359] The main functions of NR PDCP (S30, S65) may include some of the following functions:

[0360] - Header compression and decompression (ROHC only)

[0361] - User data transfer function

[0362] - In-sequence delivery of upper layer PDUs

[0363] - Out-of-sequence delivery of upper layer PDUs

[0364] - PDCP PDU reordering for reception

[0365] - Duplicate detection of lower layer SDUs

[0366] - Retransmission function (Retransmission of PDCP SDUs)

[0367] - Encryption and decryption functions (Ciphering and deciphering)

[0368] - Timer-based SDU discard in uplink.

[0369] The reordering function of the NR PDCP device above refers to a function of reordering PDCP PDUs received from a lower layer in order based on the PDCP SN (sequence number), and may include a function of transmitting data to an upper layer in the reordered order. Alternatively, the reordering function of the NR PDCP device may include a function of transmitting data directly without considering the order, a function of recording lost PDCP PDUs by reordering the order, a function of reporting a status of lost PDCP PDUs to the transmitting side, and a function of requesting retransmission of lost PDCP PDUs.

[0370] The main functions of NR RLC (S35, S60) may include some of the following functions:

[0371] - Data transfer function (Transfer of upper layer PDUs)

[0372] - In-sequence delivery of upper layer PDUs

[0373] - Out-of-sequence delivery of upper layer PDUs

[0374] - ARQ function (Error Correction through ARQ)

[0375] - Concatenation, segmentation and reassembly of RLC SDUs

[0376] - Re-segmentation of RLC data PDUs

[0377] - Reordering of RLC data PDUs

[0378] - Duplicate detection function

[0379] - Protocol error detection

[0380] - RLC SDU discard function

[0381] - RLC re-establishment function

[0382] In the above, the in-sequence delivery function of the NR RLC device refers to the function of sequentially delivering RLC SDUs received from a lower layer to an upper layer. The in-sequence delivery function of the NR RLC device may include a function of reassembling and delivering a single RLC SDU when it is received divided into multiple RLC SDUs, a function of rearranging received RLC PDUs based on the RLC SN (sequence number) or PDCP SN (sequence number), a function of recording lost RLC PDUs by rearranging the order, a function of reporting the status of lost RLC PDUs to the transmitting side, and a function of requesting retransmission of lost RLC PDUs. The in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer only the RLC SDUs up to the lost RLC SDU when there is a lost RLC SDU, or may include a function to sequentially deliver to the upper layer all RLC SDUs received before the timer starts if a predetermined timer has expired even if there is a lost RLC SDU. Alternatively, the in-sequence delivery function of an NR RLC device may include a function to sequentially deliver to the upper layer all RLC SDUs received up to the present if a predetermined timer has expired even if there is a lost RLC SDU.In addition, the RLC PDUs may be processed in the order in which they are received (in the order of arrival, regardless of the order of the sequence number) and delivered to the PDCP device out of order (out-of-sequence delivery). In the case of segments, the segments stored in the buffer or to be received later may be received, reconstructed into a 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 replaced with a multiplexing function of the NR MAC layer.

[0383] The out-of-sequence delivery function of the NR RLC device mentioned above refers to the function of directly delivering RLC SDUs received from a lower layer to an upper layer regardless of the order, and may include a function of reassembling and delivering RLC SDUs when an original RLC SDU is received divided into multiple RLC SDUs, and may include a function of storing and arranging the RLC SN or PDCP SN of received RLC PDUs to record lost RLC PDUs.

[0384] NR MAC (S40, S55) can be connected to multiple NR RLC layer devices configured in one terminal, and the main functions of NR MAC can include some of the following functions.

[0385] - Mapping function (Mapping between logical channels and transport channels)

[0386] - Multiplexing / demultiplexing of MAC SDUs

[0387] - Scheduling information reporting function

[0388] - HARQ function (Error correction through HARQ)

[0389] - Priority handling between logical channels of one UE

[0390] - Priority handling between UEs by means of dynamic scheduling

[0391] - MBMS service identification function

[0392] - Transport format selection function

[0393] - Padding function

[0394] The NR PHY layer (S45, S50) can perform operations such as channel coding and modulating upper layer data, converting it into OFDM symbols and transmitting it over a wireless channel, or demodulating and channel decoding OFDM symbols received over a wireless channel and transmitting them to a higher layer.

[0395] The above wireless protocol structure can have various detailed structures depending on the carrier (or cell) operation method. For example, when a base station transmits data to a terminal based on a single carrier (or cell), the base station and the terminal use a protocol structure that has a single structure for each layer, such as S00. On the other hand, when a base station transmits data to a terminal based on CA (carrier aggregation) that uses multiple carriers in a single TRP, the base station and the terminal use a protocol structure that has a single structure up to RLC, such as S10, but multiplexes the PHY layer through the MAC layer. As another example, when a base station transmits data to a terminal based on DC (dual connectivity) that uses multiple carriers in multiple TRPs, the base station and the terminal use a protocol structure that has a single structure up to RLC, such as S20, but multiplexes the PHY layer through the MAC layer.

[0396] [NC-JT related]

[0397] According to one embodiment of the present disclosure, Non-Coherent Joint Transmission (NC-JT) may be used for a terminal to receive PDSCH from multiple TRPs.

[0398] Unlike existing systems, 5G wireless communication systems can support not only services requiring high transmission speeds, but also services with very short transmission delays and high connection density. In a wireless communication network comprising multiple cells, transmission and reception points (TRPs), or beams, coordinated transmission between each cell, TRP, or / and beam can increase the signal strength received by a terminal or efficiently control interference between each cell, TRP, or / and beam, thereby satisfying diverse service requirements.

[0399] Joint Transmission (JT) is a representative transmission technology for the aforementioned cooperative communication, which increases the signal strength or processing rate received by a terminal by transmitting a signal to a single terminal through a number of different cells, TRPs, or / and beams. At this time, the channel between each cell, TRP, or / and beam and the terminal may have significantly different characteristics, and in particular, in the case of Non-Coherent Joint Transmission (NC-JT) that supports non-coherent precoding between each cell, TRP, or / and beam, individual precoding, MCS, resource allocation, TCI indication, etc. may be required depending on the channel characteristics of each link between each cell, TRP, or / and beam and the terminal.

[0400] The above-described NC-JT transmission can be applied to at least one channel among a downlink data channel (PDSCH: physical downlink shared channel), a downlink control channel (PDCCH: physical downlink control channel), an uplink data channel (PUSCH: physical uplink shared channel), and an uplink control channel (PUCCH: physical uplink control channel). When transmitting a PDSCH, transmission information such as precoding, MCS, resource allocation, and TCI are indicated as DL DCI, and for NC-JT transmission, the transmission information must be independently indicated for each cell, TRP, or / and beam. This is a major factor that increases the payload required for DL ​​DCI transmission, which may adversely affect the reception performance of the PDCCH transmitting the DCI. Therefore, in order to support JT of the PDSCH, it is necessary to carefully design a tradeoff between the amount of DCI information and the reception performance of control information.

[0401] FIG. 14 is a diagram illustrating an example of antenna port configuration and resource allocation for transmitting a PDSCH using cooperative communication in a wireless communication system according to one embodiment of the present disclosure.

[0402] Referring to FIG. 14, examples for PDSCH transmission are explained for each technique of Joint Transmission (JT), and examples for allocating radio resources for each TRP are shown.

[0403] Referring to FIG. 14, an example (1400) for coherent joint transmission (C-JT) supporting coherent precoding between each cell, TRP or / and beam is illustrated.

[0404] In the case of C-JT, TRP A (1405) and TRP B (1410) transmit a single data (PDSCH) to the terminal (1415), and joint precoding can be performed on multiple TRPs. This may mean that DMRS is transmitted through the same DMRS ports for TRP A (1405) and TRP B (1410) to transmit the same PDSCH. For example, TRP A (1405) and TRP B (1410) may each transmit DRMS ​​to the terminal through DMRS port A and DMRS B. In this case, the terminal may receive one DCI information for receiving one PDSCH that is demodulated based on the DMRS transmitted through DMRS port A and DMRS B.

[0405] FIG. 14 illustrates an example (1420) of Non-Coherent Joint Transmission (NC-JT) supporting non-coherent precoding between each cell, TRP, or / and beam for PDSCH transmission.

[0406] In the case of NC-JT, PDSCH is transmitted to the terminal (1435) for each cell, TRP or / and beam, and individual precoding can be applied to each PDSCH. Each cell, TRP or / and beam transmits a different PDSCH or a different PDSCH layer to the terminal, thereby improving the throughput compared to single cell, TRP or / and beam transmission. In addition, each cell, TRP or / and beam repeatedly transmits the same PDSCH to the terminal, thereby improving the reliability compared to single cell, TRP or / and beam transmission. For convenience of explanation, cells, TRPs or / and beams are collectively referred to as TRPs hereinafter.

[0407] At this time, various wireless resource allocations can be considered, such as when the frequency and time resources used by multiple TRPs for PDSCH transmission are all the same (1440), when the frequency and time resources used by multiple TRPs do not overlap at all (1445), and when some of the frequency and time resources used by multiple TRPs overlap (1450).

[0408] To support NC-JT, DCIs of various forms, structures, and relationships can be considered to simultaneously allocate multiple PDSCHs to a single terminal.

[0409] FIG. 15 is a diagram illustrating an example of a configuration of downlink control information (DCI) for NC-JT in which each TRP transmits a different PDSCH or a different PDSCH layer to a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0410] Referring to FIG. 15, case #1 (1500) is an example in which, in addition to the serving TRP (TRP#0) used for single PDSCH transmission, (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)), and control information for PDSCHs transmitted from the (N-1) additional TRPs is transmitted independently from the control information for the PDSCHs transmitted from the serving TRP. That is, the terminal can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through independent DCIs (DCI#0 to DCI#(N-1)). The formats between the independent DCIs may be the same or different, and the payloads between the DCIs may also be the same or different. In the aforementioned case #1, each PDSCH control or allocation freedom can be fully guaranteed, but if each DCI is transmitted in different TRPs, coverage differences may occur for each DCI, which may deteriorate reception performance.

[0411] Case #2 (1505) shows an example in which, in addition to the serving TRP (TRP#0) used for single PDSCH transmission, (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)), control information (DCI) for the PDSCHs of the (N-1) additional TRPs is transmitted respectively, and each of these DCIs is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0412] For example, in the case of DCI#0, which is control information for a PDSCH transmitted from a serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, but in the case of shortened DCI (hereinafter, sDCI) (sDCI#0 to sDCI#(N-2)), which is control information for PDSCHs transmitted from cooperative TRPs (TRP#1 to TRP#(N-1)), it may include only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2. Therefore, in the case of sDCI, which transmits control information for PDSCHs transmitted from cooperative TRPs, since the payload is smaller than that of normal DCI (nDCI), which transmits PDSCH-related control information transmitted from a serving TRP, it is possible to include reserved bits compared to nDCI.

[0413] In the aforementioned case #2, the degree of freedom in controlling or allocating each PDSCH may be limited depending on the content of the information elements included in sDCI, but since the reception performance of sDCI is superior to that of nDCI, the probability of a difference in coverage by DCI may be reduced.

[0414] Case #3 (1510) shows an example in which, in a situation in which (N-1) different PDSCHs are transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) other than the serving TRP (TRP#0) used for single PDSCH transmission, one control information for the PDSCHs of the (N-1) additional TRPs is transmitted, and this DCI is dependent on the control information for the PDSCH transmitted from the serving TRP.

[0415] For example, in the case of DCI#0, which is control information for PDSCH transmitted from a serving TRP (TRP#0), it includes all information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2, and in the case of control information for PDSCHs transmitted from cooperative TRPs (TRP#1 to TRP#(N-1)), it is possible to collect only some of the information elements of DCI format 1_0, DCI format 1_1, and DCI format 1_2 into one 'secondary' DCI (sDCI) and transmit them. For example, the sDCI may include at least one piece of information among HARQ-related information such as frequency domain resource assignment, time domain resource assignment, and MCS of cooperative TRPs. In addition, for information not included in sDCI, such as BWP (bandwidth part) indicator or carrier indicator, the DCI (DCI#0, normal DCI, nDCI) of serving TRP can be followed.

[0416] Case #3 (1510) may have limited freedom in controlling or allocating each PDSCH depending on the content of the information element included in sDCI, but it is possible to control the reception performance of sDCI and the complexity of DCI blind decoding of the terminal may be reduced compared to case #1 (1500) or case #2 (1505).

[0417] Case #4 (1515) is an example of transmitting control information for PDSCHs transmitted from (N-1) additional TRPs (TRP#1 to TRP#(N-1)) in the same DCI (Long DCI) as the control information for PDSCHs transmitted from the serving TRP in a situation where (N-1) different PDSCHs are transmitted from (N-1) additional TRPs in addition to the serving TRP (TRP#0) used for single PDSCH transmission. That is, the UE can obtain control information for PDSCHs transmitted from different TRPs (TRP#0 to TRP#(N-1)) through a single DCI. In case #4 (1515), the complexity of DCI blind decoding of the UE may not increase, but the degree of freedom in PDSCH control or allocation may be low, such as because the number of cooperative TRPs is limited due to the long DCI payload limitation.

[0418] In the following descriptions and examples, 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) containing PDSCH control information transmitted in a cooperative TRP, and unless a special limitation is specified, the description can be similarly applied to the various auxiliary DCIs described above.

[0419] In the following description and examples, the aforementioned cases #1 (1500), #2 (1505), and #3 (1510), in which more than one DCI (PDCCH) is used to support NC-JT, may be classified as multiple PDCCH-based NC-JT, and the aforementioned case #4 (1515), in which a single DCI (PDCCH) is used to support NC-JT, may be classified as single PDCCH-based NC-JT. In PDSCH transmission based on multiple PDCCH, a CORESET in which the DCI of the serving TRP (TRP#0) is scheduled and a CORESET in which the DCI of the cooperating TRPs (TRP#1 to TRP#(N-1)) are scheduled may be distinguished. As a method for distinguishing the CORESETs, there may be a method for distinguishing through an upper layer indicator for each CORESET, a method for distinguishing through beam setting for each CORESET, etc. Additionally, in single PDCCH-based NC-JT, instead of a single DCI scheduling multiple PDSCHs, a single PDSCH with multiple layers is scheduled, and the multiple layers described above can be transmitted from multiple TRPs. In this case, the connection relationship between a layer and the TRP transmitting the layer can be indicated through a transmission configuration indicator (TCI) indication for the layer.

[0420] In the embodiments of the present disclosure, “cooperative TRP” may be replaced with various terms such as “cooperative panel” or “cooperative beam” in actual application.

[0421] In the embodiments of the present disclosure, “when NC-JT is applied” can be interpreted in various ways depending on the situation, such as “when a terminal simultaneously receives one or more PDSCHs in one BWP,” “when a terminal simultaneously receives a PDSCH based on two or more transmission configuration indicator (TCI) indications in one BWP,” or “when a PDSCH received by a terminal is associated with one or more DMRS port groups,” but is used as a single expression for convenience of explanation.

[0422] The wireless protocol architecture for NC-JT in the present disclosure can be used in various ways depending on the TRP deployment scenario. For example, when there is no or small backhaul delay between cooperative TRPs, a method using a structure based on MAC layer multiplexing (CA-like method) similar to S10 of FIG. 13 is possible. On the other hand, when the backhaul delay between cooperative TRPs is so large that it cannot be ignored (for example, when more than 2 ms is required for information exchange such as CSI, scheduling, and HARQ-ACK between cooperative TRPs), a method (DC-like method) is possible to secure delay-robust characteristics by using an independent structure for each TRP starting from the RLC layer, similar to S20 of FIG. 13.

[0423] A terminal supporting C-JT / NC-JT can receive C-JT / NC-JT related parameters or setting values ​​from the upper layer configuration and set the RRC parameters of the terminal based on these. For the upper layer configuration, the terminal can utilize UE capability parameters, for example, tci-StatePDSCH. Here, the UE capability parameters, for example, tci-StatePDSCH, can define TCI states for the purpose of PDSCH transmission, and the number of TCI states can be set to 4, 8, 16, 32, 64, 128 in FR1, and 64 and 128 in FR2, and up to 8 states can be set among the set number that can be indicated by 3 bits of the TCI field of the DCI via the MAC CE message. The maximum value 128 means the value indicated by maxNumberConfiguredTCIstatesPerCC in the tci-StatePDSCH parameter included in the capability signaling of the terminal. In this way, a series of configuration processes from upper layer configuration to MAC CE configuration can be applied to a beamforming instruction or beamforming change command for at least one PDSCH in one TRP.

[0424] [Multi-DCI based Multi-TRP]

[0425] According to one embodiment of the present disclosure, a downlink control channel for NC-JT transmission can be set based on a multi-PDCCH.

[0426] In NC-JT based on multiple PDCCHs, when transmitting DCI for the PDSCH schedule of each TRP, a CORESET or search space can be distinguished for each TRP. The CORESET or search space for each TRP can be configured as in at least one of the following cases.

[0427] * Setting of upper layer index for each CORESET: The CORESET setting information set as an upper layer may include an index value, and the TRP transmitting the PDCCH in the corresponding CORESET may be distinguished by the set index value for each CORESET. That is, in a set of CORESETs with the same upper layer index value, it may be considered that the same TRP transmits the PDCCH, or it may be considered that a PDCCH scheduling the PDSCH of the same TRP is transmitted. The above-described index for each CORESET may be named as CORESETPoolIndex, and for CORESETs with the same CORESETPoolIndex value set, it may be considered that the PDCCH is transmitted from the same TRP. For a CORESET for which the CORESETPoolIndex value is not set, it may be considered that the default value of CORESETPoolIndex is set, and the above-described default value may be 0.

[0428] * Multiple PDCCH-Config settings: Multiple PDCCH-Configs are configured within one BWP, and each PDCCH-Config can include PDCCH settings for each TRP. That is, a list of CORESETs for each TRP and / or a list of search spaces for each TRP can be configured in one PDCCH-Config, and one or more CORESETs and one or more search spaces included in one PDCCH-Config can be considered to correspond to a specific TRP.

[0429] * CORESET Beam / Beam Group Configuration: The TRP corresponding to the CORESET can be distinguished through the beam or beam group configured for each CORESET. For example, if the same TCI state is set for multiple CORESETs, the CORESETs can be considered to be transmitted through the same TRP, or the PDCCH that schedules the PDSCH of the same TRP can be considered to be transmitted in the CORESET.

[0430] * Search space beam / beam group configuration: A beam or beam group is configured for each search space, and this allows TRPs for each search space to be distinguished. For example, if the same beam / beam group or TCI state is set for multiple search spaces, it can be considered that the same TRP transmits a PDCCH in the corresponding search space, or that a PDCCH that schedules the PDSCH of the same TRP is transmitted in the corresponding search space.

[0431] By dividing the CORESET or search space by TRP as described above, PDSCH and HARQ-ACK information classification for each TRP is possible, and this enables independent HARQ-ACK codebook generation and independent PUCCH resource use for each TRP.

[0432] The above settings can be independent for each cell or BWP. For example, a PCell may have two different CORESETPoolIndex values, while a specific SCell may not have a CORESETPoolIndex value set. In this case, it can be assumed that NC-JT transmission is configured for the PCell, while NC-JT transmission is not configured for the SCell without the CORESETPoolIndex value set.

[0433] [Single-DCI based Multi-TRP]

[0434] According to another embodiment of the present disclosure, a downlink beam for NC-JT transmission can be set based on a Single-PDCCH.

[0435] In single PDCCH-based NC-JT, PDSCHs transmitted by multiple TRPs can be scheduled with a single DCI. At this time, the number of TCI states can be used as a method of indicating the number of TRPs transmitting the corresponding PDSCH. That is, if the number of TCI states indicated in the DCI scheduling the PDSCH is two, it can be considered as a single PDCCH-based NC-JT transmission, and if the number of TCI states is one, it can be considered as a single-TRP transmission. The TCI states indicated in the above DCI can correspond to one or both of the TCI states activated by MAC-CE. When the TCI states of the DCI correspond to two TCI states activated by MAC-CE, a correspondence relationship is established between the TCI codepoint indicated in the DCI and the TCI states activated by MAC-CE, and this can be the case when there are two TCI states activated by MAC-CE corresponding to the above TCI codepoint.

[0436] The above configuration can be independent on a per-cell or per-BWP basis. For example, a PCell may have up to two activated TCI states corresponding to a single TCI codepoint, while a specific SCell may have up to one activated TCI state corresponding to a single TCI codepoint. In this case, it can be assumed that NC-JT transmission is configured on the PCell, while NC-JT transmission is not configured on the aforementioned SCell.

[0437] Referring to the descriptions of the PDCCH and beam configurations mentioned above, PDCCH repeated transmission is not supported in Rel-15 and Rel-16 NR, making it difficult to achieve the required reliability in scenarios requiring high reliability such as URLLC. Specifically, referring to the descriptions of the PDCCH transmission / reception configuration and transmission beam configuration mentioned above, in the current Rel-15 / 16 NR, within a specific PDCCH monitoring interval, for multiple CORESETs that can be set for a single or multiple cells, only other CORESETs having the same QCL-TypeD characteristics as the CORESET determined by the above-mentioned rule could be received. In other words, for multiple CORESETs that overlap in time within a specific PDCCH monitoring interval, reception was possible using only one QCL-TypeD.

[0438] Meanwhile, Rel-17 FeMIMO (further enhanced MIMO) is standardizing a method to improve the reception reliability of PDCCH through repeated transmissions on PDCCH. Representative methods for repeated transmission of PDCCH include a method of repeatedly transmitting CORESETs connected to each of multiple search spaces explicitly connected through upper layer signaling by separating time or frequency resources through different TRPs, and a method of repeatedly transmitting in a SFN (single frequency network) manner by setting multiple TCI states for one CORESET. In the case of repeated PDCCH transmissions, since repeated transmissions are performed using multiple QCL-TypeDs from multiple TRPs within a specific time period, in order to enable reception of this, the current limitation of receiving multiple overlapping CORESETs at a specific time period with only one QCL-TypeD characteristic must be relaxed.

[0439] The present disclosure provides a method for repeatedly transmitting PDCCHs using multiple transmission points (TRPs) to improve PDCCH reception reliability at a terminal. The present disclosure also provides a method for prioritizing CORESET reception during repeated PDCCH transmissions considering multiple TRPs, thereby enabling terminals to receive repeated PDCCH transmissions. Specific methods are described in detail in the following examples.

[0440] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. The contents of the present disclosure can be applied to FDD (frequency division duplex), TDD (time division duplex), XDD (cross division duplex, (or FDR (full duplex radio), SBFD (sub and non-overlapping full duplex)) systems. In the present disclosure below, upper signaling (or upper layer signaling) is a signal transmission method in which a base station transmits a signal to a terminal using a downlink data channel of a physical layer, or a terminal transmits a signal to a base station using an uplink data channel of a physical layer, and may also be referred to as RRC signaling, PDCP signaling, or MAC (medium access control) control element (MAC control element; MAC CE).

[0441] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as having the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied have a specific format, or including a specific indicator that indicates whether cooperative communication is applied, or scrambled with a specific RNTI by the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied, or assuming cooperative communication is applied in a specific section indicated by a higher layer. For the convenience of the following description, the case where the terminal receives the PDSCH to which cooperative communication is applied based on conditions similar to the above will be referred to as the NC-JT case.

[0442] For convenience, in the following description of the present disclosure, cells, transmission points, panels, beams, and / or transmission directions, which can be distinguished through upper layer / L1 parameters such as TCI state or spatial relation information, or indicators such as cell ID, TRP ID, and panel ID, are uniformly described as TRPs (transmission reception points). Therefore, in actual application, TRPs can be appropriately replaced with one of the above terms.

[0443] Hereinafter, a base station is an entity that performs resource allocation of a terminal, and may be at least one of a gNode B, a gNB, an eNode B, a Node B, a BS (base station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (user equipment), an MS (mobile station), a cellular phone, a smartphone, a computer, a terminal, or a multimedia system capable of performing a communication function.

[0444] Hereinafter, embodiments of the present disclosure will be described using a 5G system as an example, but embodiments of the present disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. For example, this may include LTE or LTE-A mobile communication and mobile communication technologies developed after 5G. Accordingly, embodiments of the present disclosure may be applied to other communication systems with some modifications within a range that does not significantly deviate from the scope of the present disclosure as determined by a person skilled in the art. The contents of the present disclosure can be applied to FDD, TDD, and XDD (FDR, SBFD) systems.

[0445] Additionally, when describing the present disclosure, detailed descriptions of related functions or configurations will be omitted if they are deemed to unnecessarily obscure the gist of the present disclosure. Furthermore, the terms described below are defined based on the functions of the present disclosure and may vary depending on the intent or custom of the user or operator. Therefore, their definitions should be based on the contents of this specification.

[0446] In the following description of the present disclosure, upper layer signaling may be signaling corresponding to at least one or a combination of one or more of the following signaling.

[0447] - MIB (master information block)

[0448] - SIB (system information block) or SIB

[0449] - RRC (radio resource control)

[0450] - MAC (medium access control) CE (control element)

[0451] In addition, L1 (layer 1) signaling may be signaling corresponding to at least one or a combination of one or more signaling methods using the following physical layer channels or signaling.

[0452] - PDCCH (physical downlink control channel)

[0453] - DCI (downlink control information)

[0454] - UE-specific DCI

[0455] - Group common DCI

[0456] - Common DCI

[0457] - Scheduling DCI (e.g. DCI used for scheduling downlink or uplink data)

[0458] - Non-scheduled DCI (e.g. DCI not intended for scheduling downlink or uplink data)

[0459] - PUCCH (physical uplink control channel)

[0460] - UCI (uplink control information)

[0461] In the present disclosure, determining the priority between A and B may be referred to in various ways, such as selecting a higher priority according to a predetermined priority rule and performing an action corresponding to it, or omitting or dropping an action for a lower priority.

[0462] The names of IEs (information elements) used in the present disclosure below are examples, and the present disclosure is not limited to the names of specific IEs.

[0463] In the present disclosure below, the above examples are described through a number of embodiments, but they are not independent and one or more embodiments may be applied simultaneously or in combination.

[0464] <Embodiment 1: Multiple TRP-based PDCCH Repetitive Transmission Method>

[0465] As one embodiment of the present disclosure, a method for repeatedly transmitting a PDCCH considering multiple TRPs is described. Repeated PDCCH transmission considering multiple TRPs can be performed in various ways depending on how each TCI state to be applied when transmitting a PDCCH in each TRP is applied to the various parameters used in the PDCCH transmission. For example, various parameters used for PDCCH transmission to which different TCI states are applied may include CCE, PDCCH candidate groups, CORESET, and search space. When repeatedly transmitting a PDCCH considering multiple TRPs, soft combining and selection methods may be considered for the terminal's reception method.

[0466] There may be the following five methods for PDCCH repetition transmission via multiple TRPs, and the base station may configure at least one of the five methods to the terminal via upper layer signaling, instruct the terminal via L1 signaling, or configure and instruct the terminal via a combination of upper layer signaling and L1 signaling.

[0467] [Method 1-1] Method for repeatedly transmitting multiple PDCCHs with the same payload

[0468] Method 1-1 is a method of repeatedly transmitting multiple control information having the same DCI format and payload. Each of the above-described control information may indicate information for scheduling a repeatedly transmitted PDSCH, for example, {PDSCH#1, PDSCH#2, ..., PDSCH#Y} repeatedly transmitted across multiple slots. The payload of each repeatedly transmitted control information is the same, which can be expressed as the PDSCH scheduling information of each control information, for example, the number of PDSCH repeated transmissions, time-domain PDSCH resource allocation information, i.e., the slot offset (K_0) between the control information and PDSCH#1 and the number of PDSCH symbols, frequency-domain PDSCH resource allocation information, DMRS port allocation information, PDSCH-to-HARQ-ACK timing, PUCCH resource indicator, etc. are all the same. The terminal can improve the reception reliability of the control information by soft combining the repeatedly transmitted control information having the same payload.

[0469] For the above-described soft combine, the terminal needs to know in advance the resource location and number of repeated transmissions of the control information to be repeatedly transmitted. To this end, the base station can instruct in advance the time domain, frequency domain, and spatial domain resource configuration of the above-described repeated transmission control information.

[0470] When control information is repeatedly transmitted along the time axis, the control information may be repeatedly transmitted across different CORESETs, repeatedly transmitted across different search space sets within a CORESET, or repeatedly transmitted across different PDCCH monitoring occasions within a CORESET and a search space set. The unit of the resource repeatedly transmitted along the time axis (e.g., CORESET unit, search space set unit, PDCCH monitoring occasion unit) and the location of the repeatedly transmitted resource (e.g., PDCCH candidate index, etc.) may be indicated through the upper layer configuration of the base station, etc. At this time, the number of times the PDCCH is repeatedly transmitted and / or the list and transmission pattern of TRPs participating in the repeated transmission may be explicitly indicated, and an upper layer indication or MAC-CE / L1 signaling, etc. may be used as an explicit indication method. At this time, the list of TRPs may be indicated in the form of a TCI state or the aforementioned QCL assumption.

[0471] When control information is repeatedly transmitted along the frequency axis, the control information may be repeatedly transmitted across different CORESETs, repeatedly transmitted across different PDCCH candidates within a CORESET, or repeatedly transmitted per CCE. The unit of resources repeatedly transmitted along the frequency axis and the location of the repeatedly transmitted resources may be indicated through the upper layer settings of the base station, etc. In addition, the number of times of repeated transmission and / or the list of TRPs participating in the repeated transmission and the transmission pattern may be explicitly indicated, and an upper layer indication or MAC-CE / L1 signaling, etc. may be used as an explicit indication method. In this case, the list of TRPs may be indicated in the form of a TCI state or the aforementioned QCL assumption.

[0472] When control information is repeatedly transmitted along a spatial axis, the control information may be repeatedly transmitted across different CORESETs, or may be repeatedly transmitted by setting two or more TCI states in one CORESET.

[0473] [Method 1-2] Method of repeatedly transmitting multiple control information that may have different DCI formats and / or payloads.

[0474] Method 1-2 is a method of repeatedly transmitting a plurality of control information (e.g., DCI) that may have different DCI formats and / or payloads. This control information schedules repeatedly transmitted PDSCHs, and the number of times each control information indicates a PDSCH repetition may be different. For example, PDCCH#1 may indicate information for scheduling {PDSCH#1, PDSCH#2, ..., PDSCH#Y}, while PDCCH#2 may indicate information for scheduling {PDSCH#2, ..., PDSCH#Y}, ..., PDCCH#X may indicate information for scheduling {PDSCH Y}. This method of repeatedly transmitting control information has the advantage of reducing the total delay time required for repeatedly transmitting control information and PDSCHs compared to Method 1-1. On the other hand, since the payloads of each repeatedly transmitted control information may be different, soft combining of the repeatedly transmitted control information is not possible, and thus the reliability may be lower than that of Method 1-1.

[0475] In the above-described method 1-2, the terminal may not need to know in advance the resource location and the number of repeated transmissions of the control information to be repeatedly transmitted, and the terminal may independently decode and process each piece of repeatedly transmitted control information. If the terminal decodes multiple pieces of repeatedly transmitted control information that schedule the same PDSCH, it may process only the first piece of repeatedly transmitted control information and ignore the second and subsequent pieces of repeatedly transmitted control information. Alternatively, the resource location and the number of repeated transmissions of the control information to be repeatedly transmitted may be indicated in advance, and the indication method may be the same as the method described in the above-described method 1.

[0476] [Method 1-3] A method of repeatedly transmitting multiple pieces of control information, each of which may have different DCI formats and / or payloads.

[0477] Method 1-3 is a method of repeatedly transmitting a plurality of control information, each of which may have different DCI formats and / or payloads. In this case, each piece of control information that is repeatedly transmitted has the same DCI format and payload. For example, the first DCI format of the first payload may be repeatedly transmitted, and also the second DCI format of the second payload may be repeatedly transmitted. Since the plurality of control information in Method 1-2 cannot be soft combined, the reliability may be lower than that of Method 1-1, and the total delay time required for repeated transmission of control information and PDSCH may be longer in Method 1-1. Method 1-3 is a method that utilizes the advantages of Method 1-1 and Method 1-2, and can transmit control information with higher reliability than Method 1-2 while reducing the total delay time required for repeated transmission of control information and PDSCH compared to Method 1-1.

[0478] In the above method 1-3, the terminal can use the soft combine of the above method 1-1 and the individual decoding of the above method 1-2 to decode and soft combine the repeatedly transmitted control information. For example, the terminal can decode the first transmitted control information among the repeatedly transmitted control information for a plurality of control information that may have different DCI formats and / or payloads, as in the above method 1-2, and soft combine the repeatedly transmitted control information for the decoded control information, as in the above method 1-1.

[0479] Meanwhile, the base station can configure the control information repetition transmission by selecting one of the above-mentioned methods 1-1, 1-2, or 1-3. The control information repetition transmission method can be explicitly indicated by the base station to the terminal through upper layer signaling. Alternatively, the control information repetition transmission method can be indicated in combination with other configuration information. For example, an upper layer configuration indicating the PDSCH repetition transmission method can be combined with the control information repetition transmission indication. If the PDSCH is indicated to be repeatedly transmitted in an FDM (frequency division multiplexing) manner, the control information can be interpreted as being repeatedly transmitted only in the above-mentioned method 1-1, because the delay time reduction effect of the above-mentioned method 1-2 is not provided in the PDSCH repetition transmission in an FDM (frequency division multiplexing) manner. For a similar reason, if the PDSCH is indicated to be repeatedly transmitted in an intra-slot TDM (time division multiplexing) manner, the control information can be interpreted as being repeatedly transmitted in the above-mentioned method 1-1. On the other hand, if the PDSCH is instructed to be repeatedly transmitted in an inter-slot TDM manner, the above-mentioned method 1-1, method 1-2 or method 1-3 for repeatedly transmitting control information can be selected through upper layer signaling or L1 signaling.

[0480] Meanwhile, a base station can explicitly instruct a terminal to repeat control information transmission units through settings of a higher layer, etc. Alternatively, the control information repetition transmission unit can be indicated in combination with other configuration information. For example, a higher layer setting indicating a PDSCH repetition transmission method can be combined with the control information repetition transmission unit. If a PDSCH is instructed to be repeatedly transmitted in an FDM manner, the control information can be interpreted as being repeatedly transmitted in FDM or SDM (space division multiplexing). This is because if the control information is repeatedly transmitted in a manner such as inter-slot TDM, there is no effect of reducing the delay time due to repeated PDSCH transmission in the FDM manner. For a similar reason, if a PDSCH is instructed to be repeatedly transmitted in an intra-slot TDM manner, the control information can be interpreted as being repeatedly transmitted in intra-slot TDM, FDM, or SDM. On the other hand, if a PDSCH is instructed to be repeatedly transmitted in an inter-slot TDM manner, the control information can be selected through higher layer signaling, etc., to be repeatedly transmitted in inter-slot TDM, intra-slot TDM, FDM, or SDM.

[0481] [Method 1-4] PDCCH transmission method that applies each TCI state to different CCEs within the same PDCCH candidate group

[0482] Method 1-4 is a method for improving PDCCH reception performance without repeated PDCCH transmissions by applying different TCI states, meaning transmissions from multiple TRPs, to different CCEs within a PDCCH candidate set. Although this method does not involve repeated PDCCH transmissions, it can be a method for achieving spatial diversity within a PDCCH candidate set by transmitting different CCEs within a PDCCH candidate set with different TCI states in each TRP. Different CCEs with different TCI states can be separated by time or frequency, and the UE needs to know in advance the resource locations where different TCI states are applied. The UE can receive different CCEs with different TCI states within the same PDCCH candidate set and decode them independently or simultaneously.

[0483] [Method 1-5] PDCCH transmission method that applies multiple TCI states to all CCEs within the same PDCCH candidate group (SFN method)

[0484] Methods 1-5 apply multiple TCI states to all CCEs within a PDCCH candidate set and transmit them in an SFN manner to improve PDCCH reception performance without repetitive PDCCH transmissions. While this method does not require repetitive PDCCH transmissions, it can be used to achieve spatial diversity through SFN transmissions at the same CCE location within the PDCCH candidate set. The UE can receive CCEs with different TCI states at the same location within the same PDCCH candidate set and independently decode them using some or all of the multiple TCI states, or decode them simultaneously.

[0485] <Example 2: Reporting terminal capabilities related to soft combining during repeated PDCCH transmissions>

[0486] A terminal can report its soft combining capabilities to the base station during repeated PDCCH transmissions. Several methods exist for this purpose. Specific methods are as follows.

[0487] [Terminal Capability Reporting Method 1] A terminal may report to a base station its capability, indicating whether soft combining is possible or not, only when repeating PDCCH transmissions. The terminal capability report includes information regarding whether soft combining is possible for the terminal's PDCCH repetitions, and the base station may provide PDCCH repetition-related settings to the terminal based on whether soft combining is possible for the terminal's PDCCH repetitions, as included in the terminal capability report.

[0488] For example, if a terminal has reported to the base station that soft combining is possible during repeated PDCCH transmission, the base station can determine whether the terminal is capable of soft combining to the greatest degree of flexibility (for example, determine that the terminal is capable of soft combining at the LLR (log likelihood ratio) level), and can notify the terminal of PDCCH repetition-related settings as flexibly as possible when configuring PDCCH transmission. In this case, as an example of PDCCH repetition settings, the base station can assume that the terminal is capable of soft combining between CORESETs or search spaces with different settings, soft combining between PDCCH candidates within the same aggregation level, or soft combining between PDCCH candidates between different aggregation levels, and can notify the terminal of the corresponding settings.

[0489] As another example, if a terminal has reported to the base station that soft combining is possible during repeated PDCCH transmission, the base station may most conservatively determine the level of soft combining possible for the terminal (e.g., determine that the terminal is capable of soft combining at the OFDM symbol level), and may most restrictively notify the terminal of PDCCH repetition-related settings when configuring PDCCH transmission. In this case, as an example of PDCCH repetition settings, the base station may assume that the terminal is capable of soft combining between multiple CORESETs having the same settings or soft combining between PDCCH candidates at the same aggregation level, and may notify the terminal of the corresponding settings.

[0490] [Terminal Capability Reporting Method 2] In order to express the soft combining operation possible at the terminal in more detail as a terminal capability compared to the above-described terminal capability reporting method 1, the terminal can divide the level of possibility of soft combining during repeated PDCCH transmission and report it as a terminal capability to the base station. That is, among each signal level generated from the terminal's receiving operation processes, the terminal can confirm the signal level at which soft combining can be applied for repeated PDCCH transmission, and report such information to the base station as a terminal capability.

[0491] For example, the terminal may indicate that soft combining is possible at the OFDM symbol level as a signal level at which soft combining can be applied, and / or may indicate that soft combining is possible at the modulation symbol level, and / or may indicate that soft combining is possible at the LLR level. Based on each signal level reported by the terminal, the base station may notify the terminal of an appropriate setting so that the terminal can perform soft combining according to the reported terminal capability.

[0492] [Terminal Capability Reporting Method 3] The terminal can inform the base station of the constraints necessary for soft combining at the terminal side when repeatedly transmitting PDCCHs through the terminal capability. For example, the terminal can report to the base station that the configuration of each CORESET including two repeated PDCCHs must be the same. As another example, the terminal can report to the base station that the two repeated PDCCH candidates must have at least the same aggregation level. The base station that has received the terminal capability can configure / perform PDCCH repeated transmission in response to the necessary constraints identified by the terminal capability.

[0493] [Terminal Capability Reporting Method 4] When a terminal receives a PDCCH repetition transmission from a base station, the terminal may report to the base station which PDCCH repetition transmission method it supports through the terminal capability. For example, the terminal may report to the base station that it supports the above method 1-5 (SFN transmission method). As another example, the terminal may report to the base station that it supports intra-slot TDM, inter-slot TDM, or FDM among the above methods 1-1 (methods for multiple PDCCH repetition transmissions with the same payload). In particular, in the case of TDM, the terminal may report to the base station the maximum value of the time interval between two repeated PDCCHs. For example, if the terminal reports the maximum value of the time interval between two repeated PDCCHs as 4 OFDM symbols, the base station may need to adjust the time interval between two repeated PDCCHs to 4 OFDM symbols or less when performing TDM-based PDCCH repetition transmission to the terminal based on the information.

[0494] The above-described terminal capability reporting methods can be configured as a combination of two or more in actual application. For example, the terminal can report that soft combining is possible at the LLR level by [terminal capability reporting method 2], simultaneously report that two repeated PDCCH candidates must have at least the same aggregation level by [terminal capability reporting method 3], and support repeated PDCCH transmissions that are TDMed by [terminal capability reporting method 4], but report the maximum time interval between two repeated PDCCHs as 4 OFDM symbols.

[0495] In addition, the terminal may report each terminal capability report according to the type of search space or DCI format, or include information for each search space within each terminal capability. For example, the terminal may report the terminal capabilities separately for the common search space and the terminal-specific search space, and may report whether PDCCH repetition transmission is not supported in the common search space, and whether PDCCH repetition transmission is supported in the terminal-specific search space while soft combining is possible. As another example, the terminal may report that PDCCH repetition transmission can be supported and soft combining can be performed for the terminal-specific DCI format, and that PDCCH repetition transmission is not supported for the common DCI format.

[0496] In addition, applications based on a combination of various terminal capability reporting methods are possible, and in this case, various embodiments of the present disclosure can be applied.

[0497] <Embodiment 3: Method for configuring PDCCH repetitive transmission and explicit connectivity>

[0498] As one embodiment of the present disclosure, a method for setting up PDCCH repetitive transmission to enable soft combining during PDCCH repetitive transmission is described.

[0499] For example, when a base station performs PDCCH repetitive transmission to a terminal based on the above-described method 1-1 (method of repetitively transmitting multiple PDCCHs having the same payload) among various PDCCH repetitive transmission methods of the present disclosure, the base station may set information that there is an explicit linkage (or association) between repeated PDCCH candidates through upper layer signaling, indicate it through L1 signaling, or set and indicate it through a combination of upper layer signaling and L1 signaling, so as to reduce the number of blind decodings by considering whether the terminal can soft combine. In more detail, various connection methods may exist as follows.

[0500] There are various ways to configure PDCCH repetition transmission and explicit connectivity through upper layer signaling, as follows.

[0501] [PDCCH repetition setting method 1] When setting information exists in upper layer signaling PDCCH-config

[0502] The base station may set PDCCH-repetition-config in the upper layer signaling PDCCH-config to configure PDCCH repetition transmission and explicit connectivity to the terminal, and the PDCCH-repetition-config may include at least one of the following information.

[0503] - PDCCH repetitive transmission method - 1 of TDM, FDM, SFN

[0504] - CORESET-search space combination(s) to be used when repeating PDCCH transmission

[0505] - CORESET index(es) - OPTIONAL

[0506] - Search space index(es) - OPTIONAL

[0507] - Aggregation level(s) for explicit connectivity - OPTIONAL

[0508] - PDCCH candidate index(es) for explicit connectivity - OPTIONAL

[0509] - Frequency resources for explicit connectivity - OPTIONAL

[0510] Based on the above information, the base station can configure the terminal for repeated PDCCH transmission through upper layer signaling.

[0511] For example, if the PDCCH repetition transmission method is set to SFN, and the CORESET index is set to 1 as the CORESET-search space combination to be used for PDCCH repetition transmission, and the search space index is not set, the UE may expect that the PDCCH will be repeatedly transmitted through the above method 1-5 (SFN transmission method) in the CORESET having the index 1. At this time, the UE may be configured with one or multiple different TCI states for the configured CORESET by upper layer signaling, or may be instructed by L1 signaling or MAC-CE signaling, or may be configured and instructed by a combination of upper layer signaling and L1 signaling or MAC-CE signaling. In addition, if the PDCCH repetition transmission method is set to SFN, the UE may not expect that a search space index is configured in the CORESET-search space combination to be used for PDCCH repetition transmission.

[0512] As another example, if the PDCCH repetition transmission method is set to TDM or FDM, and a total of two CORESET-search space combinations to be used for PDCCH repetition transmission are set, and the CORESET index is 1 and the search space index is 1 for the first combination, and the CORESET index is 2 and the search space index is 2 for the second combination, then the terminal can expect that the PDCCH will be repeatedly transmitted in the TDM or FDM manner through the above method 1-1 using the two CORESET-search space combinations. At this time, multiple TCI states that are the same or different for each configured CORESET can be set by upper layer signaling, or can be indicated by L1 signaling or MAC-CE signaling, or can be set and indicated by a combination of upper layer signaling and L1 signaling or MAC-CE signaling. Additionally, if the PDCCH repetition transmission method is set to TDM or FDM, the terminal can expect that up to two CORESET-search space combinations to be used during PDCCH repetition transmission are set, and both CORESET and search space indexes are expected to be set within each combination.

[0513] In addition, at least some of the information included in the PDCCH-repetition-config may be updated based on MAC-CE without resetting the RRC. If the base station does not configure PDCCH-repetition-config for the terminal, the terminal does not expect repeated PDCCH transmissions and can only expect a single PDCCH transmission. In other words, if PDCCH-repetition-config is not configured, the terminal does not expect repeated PDCCH transmissions and can expect a single PDCCH transmission. The aggregation level, PDCCH candidate index, and frequency resources for the explicit connectivity described above may not be configured at all or at least one of them may be configured, depending on the explicit connection method described below.

[0514] [PDCCH repetition setting method 2] When setting information exists in the upper layer signaling for the search space

[0515] The base station can notify the terminal by adding a higher-layer signal within the searchSpace, which is the upper-layer signaling for the search space, for repeated PDCCH transmission. For example, within the searchSpace, an additional higher-layer signaling parameter called repetition can be set to on or off to indicate whether the search space is used for repeated transmission. There can be one or two search spaces per bandwidth segment where repetition is set to on.

[0516] For example, if searchSpaceId is set to 1, controlResourceSetId is set to 1, and repetition is set to on in searchSpace, which is upper layer signaling for search space index 1, the terminal can expect that PDCCH repetition transmission is performed according to the above method 1-5 (SFN transmission method) in CORESET 1 connected to search space 1.

[0517] As another example, if searchSpaceId is set to 1, controlResourceSetId is set to 1, and repetition is set to on in searchSpace, which is an upper layer signaling for search space index 1, and searchSpaceId is set to 2, controlResourceSetId is set to 2, and repetition is set to on in searchSpace, which is an upper layer signaling for search space index 2, then the terminal can know that PDCCH repetition transmission is performed in TDM or FDM using the above method 1-1 between the combination of CORESET 1 + search space 1 and the combination of CORESET 2 + search space 2. The distinction between TDM and FDM can be made based on the time and frequency settings through the upper layer signaling of CORESET 1, 2 and search spaces 1, 2. Additionally, within the upper layer signaling for the search space where repetition is set to on, the aggregation level or PDCCH candidate indices for explicit connectivity described in the above [PDCCH repetition setting method 1] may be set, and / or, depending on the explicit connection method described below, neither the aggregation level nor the PDCCH candidate indices may be set, only one of the two may be set, or both may be set.

[0518] [PDCCH repetition setting method 3] When setting information exists in the upper layer signaling for the search space

[0519] In the first method, it can be set as in Table 26.

[0520] [Table 26]

[0521]

[0522] For example, PDCCH repetition can be configured. At this time, two repeated QCL-typeDs can be activated per cell or cell group. That is, when the base station activates twoQCLTypeDforPDCCHRepetition for the UE, the UE can check the two QCL-TypeD properties for multiple CORESETs that overlap during PDCCH repetition and determine and perform monitoring. twoQCLTypeDforPDCCHRepetition can be configured to configure PDCCH repetition and activate two QCL-TypeDs here (perform PDCCH monitoring using two QCL-TypeDs). The number of QCL-TypeDs configured / indicated is not limited to two and can be changed.

[0523] In the second method, it can be set as in Table 27. maxNrofSearchSpacesLinks-1 is the maximum number of search space links - 1, and can be 39, for example.

[0524] [Table 27]

[0525]

[0526] For example, the parameter SearchSpaceLinkingId can be used to link two search spaces of the same type in the same BWP. If two search spaces have the same SearchSpaceLinkingId, the UE assumes that the search spaces with the same SearchSpaceLinkingId are linked to the PDCCH repetition reference.

[0527] For example, when PDCCH repetitions are monitored in two sets of search spaces (linked search spaces), the UE does not expect the third monitored search space (SS) set to be linked to any of the two linked SS sets. For example, the two linked SS sets have the same SS set type, specifically, UE-specific search space (USS) and common search space (CSS). The two linked SS sets have the same DCI format that can be monitored.

[0528] For example, for intra-slot PDCCH repetition, the two SS sets must have the same periodicity and offset (monitoringSlotPeriodicityAndOffset) and the same duration. For example, for linking monitoring occasions (possible intervals or counts) across the two SS sets that exist in the same slot, the two SS sets have the same number of monitoring occasions within the slot, and the n-th monitoring occasion of one SS set is linked to the n-th monitoring occasion of the other SS set.

[0529] Additionally, for PDCCH repetition, SS set 0, searchSpaceSIB1, searchSpaceOtherSystemInformation, pagingSearchSpace, ra-SearchSpace, searchSpaceMCCH, searchSpaceMTCH, peiSearchSpace, sdt-SearchSpace, etc. cannot be linked with other SS sets. For example, the SS set by RecoverySearch-SpaceId cannot be linked with other SS sets for PDCCH repetition.

[0530] For example, when a scheduled serving cell is configured to be cross-carrier scheduled by a scheduling serving cell, two PDCCH candidates (having the same AL and candidate index associated with the scheduled serving cell) are linked only if two corresponding SS sets within the scheduling serving cell are linked. For example, two SS sets within the scheduled serving cell having the same SS set ID are also linked.

[0531] For example, the parameter SearchSpaceLinkingId does not apply to search spaces configured with dci-FormatsSL to monitor DCI format 3-0 or format 3-1, or to monitor format 3-0 and format 3-1.

[0532] The PDCCH configuration, which repeatedly transmits the same information described above, can be considered for at least one CORESETPoolindex, and can be extended to multiple CORESETPoolindexes. For example, considering two CORESETPoolindexes, the base station and terminal can consider multiple DCI (multi-DCI, M-DCI) situations. Specifically, the following options can be considered.

[0533] Option 1: The base station can configure the SS linked to the terminal to not be linked across two CORESETPoolindexes (M-DCI).

[0534] Option 2: The base station can configure PDCCH repetition transmission so that the SS linked to the terminal is associated with (only) one CORESETPoolIndex among multiple CORESETPoolIndexes (M-DCI + PDCCH repetition with one CORESETPoolIndex).

[0535] Option 3: The base station can configure PDCCH repetition transmission so that the SS linked to the terminal is associated with two CORESETPoolIndexes (M-DCI + PDCCH repetition with two CORESETPoolIndexes).

[0536] <Example 4: Method for determining priority upon reception of PDCCH repeated transmissions in multiple TRPs based on Single-DCI>

[0537] As one embodiment of the present disclosure, a method for determining priority upon reception of repeated PDCCH transmissions is described. Specifically, a base station and a terminal may assume that the previously described repeated PDCCH transmissions are transmitted in multiple TRPs based on a single-DCI.

[0538] A terminal may report to a base station at least one of the terminal capabilities listed below as a terminal capability related to a method for determining priority upon reception of PDCCH repetitive transmissions.

[0539] 1) Whether it is possible to include multiple CORESETs with multiple TCI states among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section.

[0540] 2) Whether it is possible to include CORESETs that are connected to multiple explicitly connected search spaces among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section.

[0541] 3) The maximum number of receivable receive beams among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring section, or the number of different TCI states or QCL-TypeD characteristics.

[0542] 4) The maximum number of different CORESETs that can be received considering 3) above for all CORESETs connected to a common search space or a terminal-specific search space among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring section.

[0543] 5) The maximum number of different CORESETs that can be received considering 3) above for CORESETs connected to a common search space among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring section.

[0544] 6) The maximum number of different CORESETs that can be received considering 3) above for a CORESET connected to a terminal-specific search space among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring section.

[0545] 7) The maximum number of CORESETs with multiple TCI states set among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring section.

[0546] 8) The maximum number of CORESET pairs connected to multiple search spaces explicitly connected among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring interval.

[0547] If the terminal does not report the above 1), or reports that it is impossible, the terminal does not expect that a single CORESET with multiple TCI states is included among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring period, and a CORESET with multiple TCI states set can expect that there is no other CORESET that overlaps in time across multiple cells in the PDCCH monitoring period of the CORESET.

[0548] Similarly, if the terminal does not report the above 2), or reports that it is impossible, the terminal may not expect that the CORESETs that are explicitly connected among the multiple search spaces that overlap in time for multiple cells in a specific PDCCH monitoring interval are included, and if the CORESETs that are individually connected to the multiple search spaces that are explicitly connected are repeatedly transmitted in FDM, the terminal may expect that no other CORESETs that overlap in time for multiple cells exist in the PDCCH monitoring interval of the corresponding CORESETs.

[0549] If the terminal reports 7) as 2 (i.e., reports the maximum number of 7) as 2), the terminal can expect that among the multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring interval, there will be up to two CORESETs with multiple TCI states set across the multiple cells in the PDCCH monitoring interval. In other words, up to two CORESETs can be connected to multiple TCI states in the PDCCH monitoring interval.

[0550] If the terminal reports the above 8) as 3 (i.e., reports the maximum number of 8) as 3), it can be expected that in a specific PDCCH monitoring interval, among the multiple CORESETs overlapping in time for multiple cells, there will be up to three pairs of CORESETs connected to each of the multiple explicitly connected search spaces across the multiple cells within the PDCCH monitoring interval. That is, in the corresponding PDCCH monitoring interval, up to three pairs of CORESETs can be connected to each of the three pairs of the multiple explicitly connected search spaces.

[0551] In addition, the information that the terminal is trying to report to the base station through the above eight terminal capabilities can be simultaneously received by using multiple different QCL-TypeD characteristics among multiple CORESETs that overlap in time. Therefore, since the above eight terminal capabilities are information on whether multiple PDCCHs can be received, there may be a reporting method that enables simultaneous reception by using multiple QCL-TypeD characteristics at any point in time.

[0552] A more generalized terminal capability can be reported to the base station as a replacement for the terminal capability for simultaneous reception based on multiple QCL-TypeD characteristics of CORESET. Instead of the eight terminal capabilities described above, the terminal capability for simultaneous reception based on multiple QCL-TypeD characteristics of CORESET can be reported. In this case, the terminal reporting the terminal capability can inform the base station that it is capable of simultaneous reception of downlink signals (e.g., multiple downlink signals such as SSB, CSI-RS, CSI-IM (CSI interference measurement), PRS (positioning reference signal), DMRS, PTRS (phase tracking reference signal), PDSCH, PDCCH, etc.) using multiple QCL-TypeD characteristics that overlap in time at any point in time. In addition, when reporting the capability, the terminal can inform the base station that it is capable of simultaneous reception of some combinations of the examples of downlink signals listed above using multiple QCL-TypeD characteristics that overlap in time at any point in time.

[0553] Below, as a specific embodiment considering PDCCH repetitive transmission, a method for determining priority when a terminal receives a PDCCH is described in detail, considering PDCCH repetitive transmission using a single CORESET in which multiple TCI states are set, or PDCCH repetitive transmission using CORESETs each connected to multiple explicitly connected search spaces.

[0554] <Example 4-1: Method for determining priority upon reception of repeated PDCCH transmissions by a terminal using a CORESET connected to each of multiple explicitly connected search spaces>

[0555] The terminal can be configured to operate in single-cell operation or carrier aggregation in the same frequency band. Furthermore, the terminal can monitor PDCCH candidates in overlapping PDCCH monitoring situations in multiple CORESETs with the same or different qcl-Types set to the 'typeD' attribute in the Active DL BWP(s) of one or more cells.

[0556] A terminal configured as above monitors PDCCH in only one CORESET and monitors other CORESETs in multiple CORESETs configured with qcl-Type set to the same 'typeD' attribute as the CORESET in the active DL BWP of the cell in one or more cells.

[0557] Here, the CORESET monitored by the terminal corresponds to the CSS set to the lowest index in the cell with the lowest index containing the CSS, if CSS is set, otherwise (if CSS is not set), it corresponds to the USS set to the lowest index in the cell with the lowest index.

[0558] The lowest USS Set Index can be determined across all USS sets having at least one PDCCH Candidate in an overlapping PDCCH Monitoring situation.

[0559] The above description basically assumes that PDCCH is repeatedly transmitted in multiple TRPs based on a single DCI.

[0560] <Example 4-2: Method for determining priority upon reception of PDCCH repetitive transmission using CORESETs each connected to multiple explicitly connected search spaces>

[0561] The UE can be configured to operate in single-cell mode or carrier aggregation mode in the same frequency band. Furthermore, the UE can monitor PDCCH candidates in situations where PDCCH monitoring overlaps across multiple CORESETs with the same or different qcl-Types set to the 'typeD' attribute in the Active DL BWP(s) of one or more cells. Furthermore, the UE can configure the twoQCLTypeDforPDCCHRepetition setting described above in the upper layer.

[0562] A terminal configured as above monitors PDCCH only in the first CORESET in which qcl-Type is set to the first 'typeD' attribute, and monitors PDCCH in multiple CORESETs having the second CORESET in which qcl-Type is set to the second 'typeD' attribute that is different from the first 'typeD' attribute. The qcl-Type set to the first or second 'typeD' attribute can be determined as follows.

[0563] The first CORESET corresponds to the CSS set with the lowest index in the cell containing the CSS set, if CSS is set, otherwise (if CSS is not set), it corresponds to the USS set with the lowest index in the cell containing the CSS set.

[0564] Except for the CSS set and USS set associated with the CORESET having the qcl-Type set to the first 'typeD' attribute, the second CORESET corresponds to the CSS set with the lowest index in the cell containing the CSS set, if CSS is set, or to the USS set with the lowest index in the cell otherwise (if CSS is not set), where either the CSS set or the USS set contains the lowest index containing any USS set associated with the CORESET having the first 'typeD' attribute or any CSS set having the same searchSpaceLinkingId value.

[0565] Here, the lowest USS set index is determined across all USS sets having at least one PDCCH candidate in the case of overlapping PDCCH monitoring.

[0566] FIG. 16 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0567] For example, referring to FIG. 16, the base station can set three CORESETs (1, 2, 3) and six CSSs (1, 2, 3, 4, 5, 6) for the terminal. In addition, specifically, the base station can set the six CSSs to have at least some or all resources overlapping in the time domain. In addition, the base station can set CSS5 to be linked with CSS6 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=0), and set CSS2 to be linked with CSS3 for PDCCH repetition transmission (searchSpaceLinkingId=1). In addition, the base station can set QCL-typeD with reference to CSI-RS1 in CORESET 1, set QCL-typeD with reference to CSI-RS2 in CORESET 2, and set QCL-typeD with reference to CSI-RS3 in CORESET 3. That is, the reference signal for QCL-typeD can be set differently in each CORESET.

[0568] Here, if a UE capability report indicating that the terminal can receive two QCL type-Ds has been previously transmitted and received between the base station and the terminal, the terminal may decide to monitor CSS1 first, which corresponds to the CSS Set with the lowest index in the cell with the lowest index containing the CSS Set. In addition, the terminal may also monitor CSS5, which has the same QCL type-D as CSS1. The terminal that has decided to monitor CSS1 may decide to monitor CSS6, which has the same value of searchSpaceLinkingId set to 0, as the second monitoring target. That is, the terminal may monitor CSS6 using the second QCL typeD, and monitor CSS3, which is set to the same QCL-TypeD. Finally, the terminal that has decided on two different QCL-TypeDs cannot monitor CSS2 and CSS4 for the remaining CORESET 2. In other words, monitoring is not performed for CSS2 and CSS4.

[0569] Although the examples described above only consider CSS, it is self-evident that they can be extended to various embodiments that include CSS and / or USS according to the described rules.

[0570] <Example 5: Method for determining priority upon reception of PDCCH repeated transmissions in multiple TRPs based on Multiple-DCI>

[0571] As one embodiment of the present disclosure, a method for determining priority upon reception of repeated PDCCH transmissions is described. Specifically, it can be assumed that the previously described repeated PDCCH transmissions are transmitted in multiple TRPs based on multiple-DCI.

[0572] In order to receive a repeatedly transmitted PDCCH, the terminal may report to the base station at least one of the terminal capabilities listed below as a terminal capability related to a priority determination method.

[0573] 1) Whether it is possible to include multiple CORESETs with multiple TCI states set among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section within the first CORESET and the second CORESET

[0574] 2) Whether it is possible to include CORESETs that are connected to multiple search spaces explicitly connected among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section within the first CORESET and the second CORESET.

[0575] 3) The maximum number of receivable reception beams or the number of different TCI states or QCL-TypeD characteristics among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring period within the first CORESET and the second CORESET.

[0576] 4) The maximum number of different CORESETs that can be received considering 3) above for all CORESETs connected to a common search space or a terminal-specific search space among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section within the first CORESET and the second CORESET.

[0577] 5) The maximum number of different CORESETs that can be received considering 3) above for CORESETs connected to a common search space among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section within the first CORESET and the second CORESET.

[0578] 6) The maximum number of different CORESETs that can be received considering 3) above for a CORESET connected to a terminal-specific search space among multiple CORESETs that overlap in time for multiple cells in a specific PDCCH monitoring section within the first CORESET and the second CORESET.

[0579] 7) The maximum number of CORESETs with multiple TCI states set among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring interval within the first CORESET and the second CORESET.

[0580] 8) The maximum number of CORESET pairs connected to multiple search spaces explicitly connected among multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring interval within the first CORESET and the second CORESET.

[0581] If the terminal does not report the above 1), or reports that it is impossible, the terminal does not expect that a single CORESET with multiple TCI states set among multiple CORESETs overlapping in time for multiple cells is included in a specific PDCCH monitoring period within the first CORESET and the second CORESET, and a CORESET with multiple TCI states set can expect that there is no other CORESET overlapping in time across multiple cells in the PDCCH monitoring period of the CORESET.

[0582] Similarly, if the terminal does not report the above 2), or reports it as impossible, the terminal may not expect that the CORESETs connected to the multiple search spaces explicitly connected among the multiple CORESETs overlapping in time for the multiple cells in the specific PDCCH monitoring intervals within the first and second CORESETs are included, and if the CORESETs connected to the multiple search spaces explicitly connected are repeatedly transmitted in FDM, it may be expected that no other CORESETs overlapping in time exist across the multiple cells in the PDCCH monitoring intervals of the corresponding CORESETs.

[0583] If the terminal reports 7) as 2 (i.e., reports the maximum number of 7) as 2), the terminal can expect that among the multiple CORESETs overlapping in time for multiple cells in a specific PDCCH monitoring interval within the first CORESET and the second CORESET, there will be up to two CORESETs with multiple TCI states set across the multiple cells within the PDCCH monitoring interval. That is, up to two CORESETs can be connected to multiple TCI states in the PDCCH monitoring interval.

[0584] If the terminal reports the above 8) as 3 (i.e., reports the maximum number of 8) as 3), it can be expected that in a specific PDCCH monitoring interval within the first CORESET and the second CORESET, for multiple cells, among the multiple CORESETs overlapping in time, there will be up to three pairs of CORESETs connected to each of the multiple search spaces explicitly connected to each other in the PDCCH monitoring interval for the multiple cells. That is, in the corresponding PDCCH monitoring interval, up to three pairs of CORESETs can be connected to each of the three pairs of the multiple search spaces explicitly connected to each other.

[0585] In addition, the information that the terminal wants to report to the base station through the above eight terminal capabilities can be simultaneously received by utilizing multiple different QCL-TypeD characteristics among multiple CORESETs that overlap in time. Therefore, since the above eight terminal capabilities are information focused on whether multiple PDCCHs can be received, there may be a reporting method that enables simultaneous reception by utilizing multiple QCL-TypeD characteristics at any point in time.

[0586] A more generalized terminal capability can be reported to the base station as a replacement for the terminal capability for simultaneous reception based on multiple QCL-TypeD characteristics of CORESET. Instead of the eight terminal capabilities described above, the terminal capability for simultaneous reception based on multiple QCL-TypeD characteristics of CORESET can be reported. In this case, the terminal reporting the terminal capability can inform the base station that simultaneous reception is possible at any point in time using multiple QCL-TypeD characteristics that overlap in time for a downlink signal (e.g., multiple downlink signals such as SSB, CSI-RS, CSI-IM, PRS, DMRS, PTRS, PDSCH, PDCCH, etc.). In addition, when reporting the capability, the terminal can inform the base station that simultaneous reception is possible at any point in time using multiple QCL-TypeD characteristics that overlap in time for only some combinations of the examples of downlink signals listed above.

[0587] In the case where there is no separate setting for PDCCH repeated transmission in multi-DCI based multiple-TRP, the QCL-TypeD priority for PDCCH monitoring is first described.

[0588] The base station can configure the terminal to operate in single-cell mode or carrier aggregation mode within the same frequency band. Furthermore, the terminal can monitor PDCCH candidates in overlapping PDCCH monitoring situations in multiple CORESETs with the same or different qcl-Types set to the 'typeD' attribute in the Active DL BWP(s) of one or more cells.

[0589] For a multiple-TRP configuration, the terminal may not set CORESETPoolIndex for the first CORESET, or may set CORESETPoolIndex value 0 for the first CORESET and CORESETPoolIndex value 1 for the second CORESET. In addition, a parameter (e.g., twoQCLTypeDforMulti-DCI) may be set to indicate whether two QCL type-D configurations for multiple DCI transmissions are enabled in a multi-DCI based multiple-TRP. If CORESETPoolIndex for a specific CORESET is not set, the CORESETPoolIndex of the specific CORESET is assumed to be 0. Therefore, an embodiment of the present disclosure may be applied to both the cases where CORESETPoolIndex 0 and 1 are set for the first CORESET and the second CORESET, respectively, and the cases where CORESETPoolIndex is not set for the first CORESET and CORESETPoolIndex 1 is set for the second CORESET. Unless specifically stated otherwise, the case where CORESETPoolIndex 0 and 1 are set may be replaced with the case where CORESETPoolIndex is not set for a specific CORESET and CORESETPoolIndex 1 is set for another CORESET. In addition, the case where CORESETPoolIndex 0 is set may be replaced with the case where CORESETPoolIndex is not set.

[0590] A terminal set as above can independently perform QCL-related monitoring operations across the first CORESET and the second CORESET.

[0591] For example, at least one PDCCH(s) is monitored in a specific CORESET within a first CORESET set to a specific CORESETPoolIndex value (e.g., CORESETPoolIndex 0), and another CORESET is monitored in an active DL BWP for one or more cells among a plurality of CORESETs whose qcl-Type is set to the same 'typeD' attribute as the specific CORESET within the first CORESET. Here, the specific CORESET being monitored corresponds to the CSS set to the lowest index in the cell with the lowest CSS index, if CSS is set, or otherwise corresponds to the USS set to the lowest index in the cell with the lowest index. The lowest USS Set Index can be determined across all USS sets having at least one PDCCH Candidate in an overlapping PDCCH Monitoring situation.

[0592] For another example, at least one PDCCH(s) is monitored in a specific CORESET within a second CORESET set to a specific CORESETPoolIndex value (e.g., CORESETPoolIndex 1), and another CORESET is monitored in an active DL BWP for one or more cells among a plurality of CORESETs whose qcl-Type is set to the same 'typeD' attribute as the specific CORESET within the second CORESET. Wherein the specific CORESET being monitored corresponds to the CSS set to the lowest index in the cell containing the CSS, if CSS is set, or otherwise corresponds to the USS set to the lowest index in the cell with the lowest index. The lowest USS Set Index can be determined across all USS sets having at least one PDCCH Candidate in an overlapping PDCCH Monitoring situation.

[0593] As described above, for PDCCH monitoring without separate settings for repeated PDCCH transmission in multi-DCI-based multiple-TRP, the number of QCL type-Ds supported by the terminal can be determined as a UE capability as follows, which can be transmitted and received between the base station and the terminal. The number of QCL type-Ds is an example and the present disclosure is not limited thereto.

[0594] - Supports up to 2 per CORESETPoolIndex

[0595] - Supports 1 per CORESETPoolIndex

[0596] - Supports 2 / 3 / 4 for all CORESETPoolIndexes

[0597] As a specific embodiment considering PDCCH repetitive transmission in a multi-DCI based multiple-TRP, a method for determining priority upon PDCCH reception is described in detail, considering PDCCH repetitive transmission using a single CORESET in which multiple TCI states are set or PDCCH repetitive transmission using CORESETs each connected to multiple explicitly connected search spaces.

[0598] <Example 5-1: Method for determining priority upon reception of PDCCH repetitive transmission using CORESETs each connected to multiple explicitly connected search spaces>

[0599] The terminal can be configured to operate in single-cell operation or carrier aggregation in the same frequency band. Furthermore, the terminal can monitor PDCCH candidates in overlapping PDCCH monitoring situations in multiple CORESETs with the same or different qcl-Types set to the 'typeD' attribute in the Active DL BWP(s) of one or more cells.

[0600] For the terminal, the CORESETPoolIndex for the first CORESET may not be set, or the CORESETPoolIndex value 0 may be set for the first CORESET(s) and the CORESETPoolIndex value 1 may be set for the second CORESET, and a parameter indicating whether two QCL type-D configurations for multiple DCI transmissions are enabled (e.g., twoQCLTypeDforMulti-DCI) may be set. In addition, the terminal may set twoQCLTypeDforPDCCHRepetition as described above in the upper layer.

[0601] A terminal configured as above monitors PDCCH only in the first CORESET whose qcl-Type is set to the first 'typeD' attribute for at least one CORESETPoolIndex, and monitors PDCCH in multiple CORESETs having the second CORESET whose qcl-Type is set to the second 'typeD' attribute that is different from the first 'typeD' attribute. The qcl-Type set to the first 'typeD' attribute or the second 'typeD' attribute can be determined as follows.

[0602] The first CORESET corresponds to the CSS set with the lowest index in the cell containing the CSS set, if CSS is set, otherwise (if CSS is not set), it corresponds to the USS set with the lowest index in the cell containing the CSS set.

[0603] Except for the CSS set and USS set associated with the CORESET having the qcl-Type set to the first 'typeD' attribute, the second CORESET corresponds to the CSS set with the lowest index in the cell containing the CSS set, if CSS is set, or to the USS set with the lowest index in the cell otherwise (if CSS is not set), where either the CSS set or the USS set contains the lowest index containing any USS set associated with the CORESET having the first 'typeD' attribute or any CSS set having the same searchSpaceLinkingId value.

[0604] Here, the lowest USS set index is determined across all USS sets having at least one PDCCH candidate in the case of overlapping PDCCH monitoring.

[0605] In other words, the previously described embodiment 4-2 can be extended to independently repeat the process for each CORESETpoolindex. A difference or addition compared to the previously described embodiments may be that the number of QCL-typeDs to be applied and the criteria for monitoring overlapping PDCCHs in the time domain between the base station and the terminal may need to be further defined. One embodiment of the present disclosure regarding this is described below.

[0606] Alt1-1) If the terminal reports to the base station that it supports at most two QCL-typeDs (maximum value of QCL-typeD = 2 (maximum number of QCL-typeD = 2)), the base station can determine that the terminal supports at most two QCL-TypeDs in all time domains. If the base station sets CORESETPoolIndex 0, 1 to the terminal, the terminal does not expect to set more than two different QCL-typeDs. That is, the terminal expects that the number of QCL-typeDs set for the multiple CORESETs set is two or less. Here, the multiple CORESETs correspond to CORESETPoolIndex 0, 1.

[0607] In such an embodiment, it can be assumed that the connected SSs within a CORESET where the CORESETpoolindex is set to 0 or the CORESETpoolindex is set to 1 are not set to overlap each other for each CORESETpoolindex, but only the SSs linked within one CORESETpoolindex value overlap. Ultimately, the terminal can check the SS set for repeated transmission for each CORESETpoolindex and apply the embodiment 4-2 described above.

[0608] Alt1-2) If the terminal reports to the base station that it supports up to 4 QCL-typeDs (maximum value of QCL-typeD = 4 (maximum number of QCL-typeD = 4)), the base station can determine that the terminal supports up to 2 QCL-TypeDs for each CORESETPoolIndex. If the base station sets CORESETPoolIndex 0 and 1 for the terminal, the terminal does not expect to set more than 2 different QCL-typeDs for each CORESETPoolIndex. That is, the terminal expects that no more than 2 QCL-typeDs are set for CORESETs corresponding to CORESETPoolIndex 0 among the set multiple CORESETs, and also expects that no more than 2 QCL-typeDs are set for CORESETs corresponding to CORESETPoolIndex 1 among the multiple CORESETs. In such an embodiment, the connected SSs within a CORESET with CORESETpoolindex set to 0 or CORESETpoolindex set to 1 can be configured to overlap each other for each CORESETpoolindex, and it can be assumed that only SSs within one CORESETpoolindex value overlap. Ultimately, the terminal can check the SSs configured for repeated transmission for each CORESETpoolindex and apply two QCL-typeDs for each CORESETpoolindex by extending the embodiment 4-2 described above.

[0609] FIG. 17 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0610] For example, referring to FIG. 17, the base station can set five CORESETs (1, 2, 3, 4, 5) and nine CSSs (1, 2, 3, 4, 5, 6, 7, 8, 9) to the terminal. Specifically, the base station can set two CORESETpoolindexes. For example, the base station can set CORESETs 1, 3, 5 including CORESETpoolindex 0, and CORESETs 2, 4 including CORESETpoolindex 1.

[0611] The relationship between the settings of CORESET 1 to CORESET 5 and the settings of CSS1 to CSS9 is illustrated in Fig. 17. That is, CSS1 and CSS3 can be set for CORESET1 corresponding to CORESETpoolindex 0, CSS2 and CSS4 can be set for CORESET3, and CSS5 and CSS6 can be set for CORESET5. In addition, CSS7 and CSS9 can be set for CORESET2 corresponding to CORESETpoolindex 1, and CSS8 can be set for CORESET4. This also applies to the examples of Figs. 18 to 21 below.

[0612] Here, the base station can additionally configure linked (CSS1, CSS2) and (CSS7, CSS8) for PDCCH that is repeatedly transmitted to the terminal. In this way, the base station can configure up to 4 QCL-typeDs for each CORESETpoolindex considering the capabilities of the terminal. For example, the base station can configure CSS1 in the upper layer (e.g., searchSpaceLinkingId=0) to be linked with CSS2 for repeated PDCCH transmission, and can configure CSS7 to be linked with CSS8 for repeated PDCCH transmission (e.g., searchSpaceLinkingId=1). Additionally, the base station can set QCL-typeD by referring to CSI-RS1 in CORESET 1 and 5, set QCL-typeD by referring to CSI-RS2 in CORESET 3, set QCL-typeD by referring to CSI-RS3 in CORESET 2, and set QCL-typeD by referring to CSI-RS4 in CORESET 4.

[0613] Here, if the UE capability that the terminal can receive two QCL type-Ds per CORESETpoolindex is previously reported between the base station and the terminal, or if it is reported that the terminal can receive all four QCL type-Ds simultaneously, the monitoring priority of the CSS determined by the terminal may be determined such that, for CORESETpoolindex 0, CSS1 in CORESET1 is the highest, followed by CSS2 associated therewith, and for CORESETpoolindex 1, CSS7 is the highest, followed by CSS8 associated therewith. Accordingly, in the example of FIG. 17, the terminal can monitor and receive all PDCCHs that are repeatedly transmitted and configured by the base station even if at least some resources overlap.

[0614] Although the examples described above only consider CSS, it is self-evident that they can be extended to various embodiments that include CSS and / or USS according to the described rules.

[0615] Alt2) If the terminal reports to the base station that it supports up to 2 / 3 / 4 QCL-typeDs (maximum value of QCL-typeD = 2 / 3 / 4 (maximum number of QCL-typeD = 2 / 3 / 4)), and the base station sets the monitoring occasions for the terminal to receive the repeatedly transmitted PDCCH to overlap in the time domain, the terminal can perform monitoring in the order considering a specific CORESETPoolIndex.

[0616] For example, if PDCCHs repeatedly transmitted from two CORESETpoolindexes overlap, the lowest CORESETpoolindex or CORESETpoolindex 0 may be monitored with priority within the capability of the terminal. That is, the terminal may perform CSS and / or USS monitoring set to 0 or 1 within the limit that does not exceed the simultaneous reception QCL-TypeD capability of the terminal, and may determine not to perform monitoring for the next CORESETPoolIndex (e.g., 1) for the number of QCL-TypeDs exceeding the capability.

[0617] FIG. 18 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0618] For example, referring to FIG. 18a, the base station can set five CORESETs (1, 2, 3, 4, 5) and nine CSSs (1, 2, 3, 4, 5, 6, 7, 8, 9) to the terminal. Specifically, the base station can set two CORESETPoolIndexes. For example, the base station can set CORESETs 1, 3, 5 including CORESETPoolIndex 0, and CORESETs 2, 4 including CORESETPoolIndex 1. The relationship between the settings of CORESETs 1 to 5 and the settings of CSSs 1 to CSS9 is illustrated in FIG. 18a. Here, the base station can additionally set connected (CSS1, CSS2) and (CSS7, CSS8) for PDCCH repeatedly transmitted to the terminal. In this way, the base station can set up to two QCL-typeDs for each CORESETPoolIndex, taking into account the capabilities of the terminal.

[0619] For example, the base station can configure CSS1 to be linked with CSS2 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=0), and CSS7 to be linked with CSS8 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=1). In addition, the base station can configure QCL-typeD with reference to CSI-RS1 in CORESET 1 and 5, QCL-typeD with reference to CSI-RS2 in CORESET 3, QCL-typeD with reference to CSI-RS4 in CORESET 2, and QCL-typeD with reference to CSI-RS5 in CORESET 4.

[0620] Here, if the UE capability is previously reported between the base station and the UE that the UE can receive up to two QCL type-Ds simultaneously, the monitoring priority of the CSS determined by the UE may be determined such that CSS1 in CORESET1 is the highest, and CSS2 associated therewith is the next highest, for CORESETpoolindex 0. Here, since the UE has already determined two different QCL-typeDs, it may not perform monitoring for CORESETs (e.g., CORESET 2, 4, 5) or CSSs (e.g., CSS 5 to 9) set to other QCL-TypeDs thereafter.

[0621] Although the examples described above only consider CSS, it is self-evident that they can be extended to various embodiments that include CSS and / or USS according to the described rules.

[0622] For another example, referring to FIG. 18b, the base station can set five CORESETs (1, 2, 3, 4, 5) and nine CSSs (1, 2, 3, 4, 5, 6, 7, 8, 9) for the terminal. Specifically, the base station can set two CORESETpoolindexes. For example, the base station can set CORESETs 1, 3, 5 including CORESETpoolindex 0, and CORESETs 2, 4 including CORESETpoolindex 1. The relationship between the settings of CORESETs 1 to 5 and the settings of CSSs 1 to CSS9 is illustrated in FIG. 18b. Here, the base station can additionally set (CSS1, CSS2) and (CSS7, CSS8) connected for PDCCH repeatedly transmitted to the terminal. In this way, the base station can set up to two QCL-typeDs for each CORESETpoolindex considering the capabilities of the terminal.

[0623] For example, the base station can configure CSS1 to be linked with CSS2 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=0), and CSS7 to be linked with CSS8 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=1). In addition, the base station can configure QCL-typeD with reference to CSI-RS1 in CORESET 1 and 5, configure QCL-typeD with reference to CSI-RS2 in CORESET 2 and 3, configure QCL-typeD with reference to CSI-RS2 in CORESET 2, and configure QCL-typeD with reference to CSI-RS3 in CORESET 4.

[0624] Here, if the UE capability that the terminal can receive up to two QCL type-Ds simultaneously has been previously reported between the base station and the terminal, the monitoring priority of the CSS determined by the terminal may be determined such that CSS1 in CORESET1 has the highest priority for CORESETpoolindex 0, and CSS2 associated with it may be determined next. Here, although the terminal has already determined two different QCL-typeDs, since CORESETs 2 and 3 are the same QCL-typeD, the terminal may include CSS7 and CSS8 associated with CORESETpoolindex 1 in the monitoring occasion. However, the terminal cannot perform monitoring on CSS8 because it is set to a different QCL typeD even though it is connected to CSS7. In other words, monitoring may not be performed on a CORESET (e.g., CORESET 4) or CSS (e.g., CSS 8) set to a different QCL-TypeD.

[0625] As another example, a terminal may determine not to monitor either CSS7 or CSS8 for repeatedly transmitted PDCCHs. This may be determined by the standard, or may be determined by the terminal's choice in a commercial setting.

[0626] Although the examples described above only consider CSS, it is self-evident that they can be extended to various embodiments that include CSS and / or USS according to the described rules.

[0627] FIG. 19 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0628] Referring to FIG. 19, the base station can set five CORESETs (1, 2, 3, 4, 5) and nine CSSs (1, 2, 3, 4, 5, 6, 7, 8, 9) for the terminal. Specifically, the base station can set two CORESETpoolindexes. For example, the base station can set CORESETs 1, 3, 5 including CORESETpoolindex 0, and CORESETs 2, 4 including CORESETpoolindex 1. The relationship between the settings of CORESETs 1 to 5 and CSS1 to CSS9 is exemplified in FIG. 19. Here, the base station can additionally set (CSS1, CSS2) and (CSS7, CSS8) connected for PDCCH repeatedly transmitted to the terminal. In this way, the base station can set up to three QCL-typeDs for each CORESETpoolindex considering the capabilities of the terminal.

[0629] For example, the base station can configure CSS1 to be linked with CSS2 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=0), and CSS7 to be linked with CSS8 for PDCCH repetition transmission (e.g., searchSpaceLinkingId=1). In addition, the base station can configure QCL-typeD with reference to CSI-RS1 in CORESET 1 and 5, QCL-typeD with reference to CSI-RS2 in CORESET 3, QCL-typeD with reference to CSI-RS3 in CORESET 2, and QCL-typeD with reference to CSI-RS4 in CORESET 4.

[0630] Here, if the UE capability that the terminal can receive up to three QCL type-Ds simultaneously has been previously reported between the base station and the terminal, the monitoring priority of the CSS determined by the terminal may be determined such that CSS1 in CORESET1 has the highest priority for CORESETpoolindex 0, and CSS2 associated with it may be determined next. Here, the terminal may include CSS7 and CSS9, which correspond to CORESET 2 with the higher priority among CORESET 2 and 4 for CORESETpoolindex 1, in the monitoring occasion since two different QCL-typeDs have been determined for CORESETpoolindex 0, and one more is possible. However, the terminal cannot perform monitoring on CSS8 because it is set to a different QCL typeD even though it is connected to CSS7. That is, monitoring may not be performed on a CORESET (e.g., CORESET 4) or CSS (e.g., CSS 8) set to a different QCL-TypeD.

[0631] As another example, a terminal may determine not to monitor either CSS7 or CSS8 for repeatedly transmitted PDCCHs. This may be determined by the standard, or may be determined by the terminal's choice in a commercial setting.

[0632] Although the examples described above only consider CSS, it is self-evident that they can be extended to various embodiments that include CSS and / or USS according to the described rules.

[0633] Alt3) If the terminal reports to the base station that it supports up to 2 / 3 / 4 QCL-typeDs (maximum value of QCL-typeD = 2 / 3 / 4 (maximum number of QCL-typeD = 2 / 3 / 4)), and the base station sets the monitoring occasion of the reception of repeatedly transmitted PDCCHs to overlap in the time domain, the terminal can perform monitoring according to the lowest CORESETPoolIndex (Alt3-1) or the lowest QCL-typeD (searchSpaceLinkingId, Alt3-2) within each CORESETPoolIndex according to the principle agreed upon with the base station (predefined rule between the terminal and the base station).

[0634] Alt3-1) Priority CORESETPoolIndex 0 - 1st QCL-TypeD > CORESETPoolIndex 0 - 2nd QCL-TypeD > CORESETPoolIndex 1 - 1st QCL-TypeD > CORESETPoolIndex 1 - 2nd QCL-TypeD (i.e. ID > 1st QCL-typeD. After CORESETPoolIndex is considered first, QCL-typeD can be considered.)

[0635] According to the priority order described above, monitoring can be given priority in the order of highest (largest) priority. The Alt3-1 embodiment is similar to the Alt2 embodiment described above, so its description will be omitted. For specific details, please refer to the description of Alt2 described above.

[0636] Alt3-2) Priority CORESETPoolindex 0-1st QCL-TypeD > CORESETPoolindex 1-1st QCL-TypeD > CORESETPoolindex 0-2nd QCL-TypeD > CORESETPoolindex 1-2nd QCL-TypeD (i.e. ID < 1st QCL-typeD. After QCL-typeD is considered first, CORESETPoolIndex can be considered.)

[0637] According to the priority order described above, monitoring can be given priority in order of higher (larger) priority.

[0638] FIG. 20 is a diagram illustrating a method for determining a priority upon reception for PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0639] Referring to FIG. 20, the base station can configure 5 CORESETs and 9 CSSs for the terminal. Specifically, the base station can configure 2 CORESETpoolindexes. For example, the base station can configure CORESETs 1, 3, and 5 including CORESETpoolindex 0, and CORESETs 2 and 4 including CORESETpoolindex 1. The relationship between the configuration of CORESETs 1 to 5 and the configuration of CSS1 to CSS9 is illustrated in FIG. 20. Here, the base station can configure (CSS7, CSS8) linked for PDCCH that is repeatedly transmitted to the terminal. In this way, the base station can configure up to 3 QCL-typeDs across the entire CORESETpoolindex considering the capabilities of the terminal. For example, the base station can configure CSS7 to be linked with CSS8 for PDCCH repeated transmission (e.g., searchSpaceLinkingId=0). Additionally, the base station can set QCL-typeD by referring to CSI-RS1 to 5 in CORESET 1 to 5, respectively.

[0640] If, among two CORESETpoolindexes, the base station and the terminal overlap in the PDCCH repeatedly transmitted in the CORESETpoolindex (e.g., 1) according to the agreed-upon principle (predefined rule), the terminal may monitor the first QCL-TypeD of CORESET 1 of CORESETpoolindex 0 as a priority within the capability of the terminal. Next, the terminal may monitor the QCL-typeD of CSS 7, 9 corresponding to CORESET 2 set in CORESETPoolIndex 1 and CSS8 (CSS8 connected to CSS7) for the PDCCH repeatedly transmitted in CSS7, if the first QCL-TypeD is set in CORESET 2 of CORESETPoolIndex 1, within the limit that does not exceed the QCL-TypeD capability that the terminal can simultaneously receive. This means that the terminal continues to monitor for CORESETpoolindex 0 because it has not yet satisfied the maximum number of QCL-typeDs, and can perform monitoring for CSS 7 to 9 of CORESET 2 and 4 because it has satisfied the maximum number of QCL-typeDs (e.g., 3) for monitoring PDCCHs that are repeatedly transmitted for CORESETpoolindex 1. Finally, the terminal can stop monitoring for CSS 2, 4, 5, and 6 of the remaining CORESETs 3 and 5.

[0641] Alt4) If the terminal reports to the base station that it supports up to 2 / 3 / 4 QCL-typeDs (maximum value of QCL-typeD = 2 / 3 / 4 (maximum number of QCL-typeD = 2 / 3 / 4)), and the base station sets the monitoring occasions for the terminal to receive the repeatedly transmitted PDCCH to overlap in the time domain, the terminal performs monitoring by giving priority to a specific CORESETPoolIndex or a specific searchSpaceLinkingId set by the base station in a higher layer (e.g., RRC configuration and / or MAC-CE message), and may give up monitoring for QCL-typeDs that exceed the capability.

[0642] Alt4-1. The gNB can set a high priority CORESETPoolindex (e.g. CORESETPoolIndex 0 or 1) in RRC to the UE.

[0643] Alt4-2. The gNB may set a high priority searchSpaceLinkingId (e.g., searchSpaceLinkingId 0 or 1) in RRC to the UE.

[0644] The various examples below are explained assuming that the terminal reports to the base station that it supports up to three QCL-typeDs (maximum value of QCL-typeD = 3 (maximum number of QCL-typeD = 3)).

[0645] FIG. 21 is a diagram illustrating a method for determining a priority upon reception of PDCCH repetitive transmission according to one embodiment of the present disclosure.

[0646] For example, as shown in FIG. 21, the base station can set five CORESETs (1, 2, 3, 4, 5) and nine CSSs (1, 2, 3, 4, 5, 6, 7, 8, 9) to the terminal. Specifically, the base station can set two CORESETpoolindexes. For example, the base station can set CORESETs 1, 3, 5 including CORESETpoolindex 0, and CORESETs 2, 4 including CORESETpoolindex 1. The relationship between the settings of CORESETs 1 to 5 and the settings of CSSs 1 to CSS9 is illustrated in FIG. 21. Here, the base station can set connected (CSS1, CSS2) and (CSS7, CSS8) for PDCCH repeatedly transmitted to the terminal. In this way, the base station can set up to three QCL-typeDs across the entire CORESETpoolindex considering the capabilities of the terminal. For example, the base station can configure CSS1 to be linked with CSS2 for PDCCH repeat transmission (e.g., searchSpaceLinkingId=0), and CSS7 to be linked with CSS8 for PDCCH repeat transmission (e.g., searchSpaceLinkingId=1). In addition, the base station can configure QCL-typeD by referring to CSI-RS1 to 5 in CORESET 1 to 5.

[0647] If the PDCCH repeatedly transmitted in the CORESETpoolindex (e.g., 1 or searchSpaceLinkingId 1) set by the base station overlaps among two CORESETpoolindexes, the terminal may monitor the CORESETpoolindex or searchSpaceLinkingId set by the base station with priority within the capability of the terminal. That is, if CORESETPoolIndex 1 or searchSpaceLinkingId 1 is set, the terminal may first monitor the QCL-typeD of CSS7, 9 for the PDCCH repeatedly transmitted among CSS 7 to 9 corresponding to CORESET 2, 4 set in CORESETPoolIndex 1 or searchSpaceLinkingId 1, and then monitor the QCL-typeD of CSS8 within the limit that does not exceed the QCL-TypeD capability that the terminal can simultaneously receive.

[0648] Since the terminal can still monitor one additional QCL-typeD, it can continue monitoring for the next CORESETPoolIndex (e.g., 0) or searchSpaceLinkingId (e.g., 0). The terminal can select CSS 1, 3 of CORESET 1 among CORESETPoolIndex 0, which has the highest priority, and perform monitoring. As a result, the terminal can stop monitoring the remaining CORESETs 3, 5.

[0649] Although the above embodiments describe embodiments for CORESETPoolindex or searchSpaceLinkingId, embodiments that consider both simultaneously are also possible and are not excluded from the scope of the present disclosure.

[0650] Additionally, the various embodiments of the present disclosure described above may be applied individually and / or in combination with each other. An example of a combined embodiment is described in alt-5 below.

[0651] Alt5) If the terminal reports to the base station that it supports up to 2 / 3 / 4 QCL-typeDs (maximum value of QCL-typeD = 2 / 3 / 4 (maximum number of QCL-typeD = 2 / 3 / 4)), and the base station sets the monitoring occasion of the reception of repeatedly transmitted PDCCHs to overlap in the time domain, the terminal determines the priority of CORESETpoolindex by the principle according to an embodiment of the present disclosure in alt 1 to 4, and additionally, performs monitoring by giving priority to CSS or USS whose specific searchSpaceLinkingId set by the base station in a higher layer (e.g., RRC configuration and / or MAC-CE message) is equal to CORESETpoolindex, and may give up monitoring for QCL-typeDs that exceed the capability.

[0652] That is, in Alt5, QCL precedence rules can be applied based on a configuration where a CSS set or USS set contains any USS set associated with a CORESET that has a searchSpaceLinkingId with the same value as any CSS set or a qcl-Type set as the first 'typeD' property in the higher-priority CORESETPoolindex.

[0653] FIG. 22 is a flowchart illustrating the operation of a terminal for receiving repeatedly transmitted PDCCHs according to one embodiment of the present disclosure. Various modifications may be made to the method illustrated in the flowchart of FIG. 22. For example, although illustrated as a series of steps, various steps in each drawing may overlap, occur in parallel, occur in different orders, or occur multiple times. In other examples, steps may be omitted or replaced with other steps. FIG. 22 may be specifically applied to various embodiments of FIGS. 16 to 21, and the order may be changed depending on the situation.

[0654] In operation 2210, the terminal may report terminal capabilities related to PDCCH repetition transmission to the base station. For example, the reported information may include information regarding terminal capabilities related to QCL upon PDCCH (repetition) reception.

[0655] In operation 2220, the terminal may receive various configuration information for the PDCCH in the upper layer configuration. For example, the received configuration information may include at least one of CORESET and search space (SS) configuration information, a repeated transmission method, a number of repeated transmissions, a repeated transmission interval, a repeated transmission cycle, a PDCCH monitoring occasion in which repeated transmission is assumed, a CORESET+search space in which repeated transmission is set, a maximum number of different QCL-TypeDs or CORESETs that can be received, a priority determination method, an aggregation level, a PDCCH candidate group, a frequency resource, and a connected SS resource.

[0656] In operation 2230, the terminal can confirm that there are multiple CORESETs overlapping in time in a specific PDCCH monitoring section, and determine a reception method by confirming the monitoring section based on the setting information.

[0657] Below, we describe the capabilities of a terminal considering combinations such as support for multiple TRPs, support for multiple DCIs, and support for PDCCH repetition.

[0658] Specifically, Table 28 below summarizes the UE capabilities related to multi-DCI multi-TRP (MDCI MTRP) support, PDCCH repetition (repeated transmission of the same downlink control channel information), simultaneous support of both functions for multi-DCI multi-TRP (MDCI MTRP) and PDCCH repetition, simultaneous support of both functions for PDCCH repetition and simultaneous reception of different QCL-TypeDs, and simultaneous reception of different QCL-TypeDs when supporting MDCI MTRP.

[0659] Specifically, UE capability describes functional features based on feature / index / feature group, and specifies whether the feature is mandatory / optional, which feature group is mandatory, whether the gNB needs to know whether the feature is supported, what happens if the UE does not support the feature, whether the UE capability type is defined 1) per UE, 2) per band, 3) per band combination, 4) per FS (Feature Set), or 5) per FSPC (Feature Set Per Component-carrier), whether FDD / TDD distinction is required, FR1 / FR2 distinction is required, and specific features are shown based on FDD / TDD and / or FR (frequency range)1 / FR2 combinations.

[0660] [Table 28]

[0661]

[0662]

[0663]

[0664] The various embodiments described above can be operated in conjunction with the UE capability reporting based on Table 28 above, and are briefly summarized into five categories as shown in Table 29. For detailed characteristics of each detailed FG (feature group), refer to the descriptions of Components and Notes in Table 28.

[0665] [Table 29]

[0666]

[0667] The terminal may report to the base station whether it supports the functions of the above five feature (group) functions based on an identifier corresponding to at least one of the feature, index, and feature group in Table 28. Support for at least one of the above five feature (group) functions may be reported.

[0668] For example, when a terminal reports that it supports both MDCI and repeatedly transmitted PDCCH reception, such as 3 (FG 23-2-4), it may include as mandatory support for MDCI-based MTRP reception capability of 1 (FG 16-2a) and / or repeatedly transmitted PDCCH reception support capability of 2 (FG 23-2-1). That is, the terminal may define capabilities 1 (FG 16-2a) and 2 (FG 23-2-1) as “pre-requisites” for capability 3 (23-2-4) in the capability report.

[0669] For another example, when a terminal reports that it supports two QCL-Type Ds for Time-domain overlapping CORESET or Intra-band carrier aggregation (CA) within the same CC (component carrier) when configuring PDCCH repetition of the terminal as in No. 4, it may include support for receiving PDCCHs transmitted twice as a mandatory requirement. That is, the terminal may define capability 2 (FG 23-2-1) as a “prerequisite” for capability 4 (FG 23-2-2) in the capability report.

[0670] For another example, when a terminal reports that it supports two QCL-Type D for intra-band CA associated with time-domain overlapping CORESETs or coresetPoolIndex values ​​0 and 1 on the same CC, such as FG 55-7, it may also include mandatory support for MDCI-based MTRP reception capability of FG 16-2a. That is, the terminal may define capability 1 (FG 16-2a) as a “pre-requisite” for capability 5 (FG 55-7) in its capability report.

[0671] For another example, when a terminal reports one or more of the above five UE capabilities, it may only report on specific combinations. That is, there may be specific restrictions on reporting the above five UE capabilities, such that when reporting a specific UE capability, another specific UE capability must be reported, or there may be restrictions that prevent reporting.

[0672] The above examples are merely a brief description of a few cases combined. The following description categorizes and re-explains representative methods. The following description refers to Table 29 above.

[0673] [Alt 6-0]

[0674] If a terminal reports at least one of UE capability features 1 to 5 to the base station, additional prerequisite requirements other than those already determined may not be required. That is, if a terminal selects at least one of features 1 to 3 and reports it to the base station, transmission of UE capability reports 4 and 5 is not restricted.

[0675] For example, when a terminal selects all of capabilities 1 to 3 and reports them to the base station, UE capability reports for capabilities 4 and 5 may be omitted. This means that when reporting capabilities 1 to 3, capability information for capabilities 4 and 5 is not included and is not reported separately thereafter. For another example, when a terminal selects all of capabilities 1 to 3 and reports them to the base station, capability information for at least one of capability 4 and / or capability 5 may be reported. This means that when reporting capabilities 1 to 3, capability information for at least one of capability 4 and / or capability 5 is included or is reported separately thereafter.

[0676] For another example, after the terminal reports all three to the base station in relation to 3, 4, and 5, if the base station sets information for receiving a PDCCH (PDCCH repetition) corresponding to capability 4 to the terminal and sets multiple TRPs based on multiple DCIs corresponding to capability 5, the terminal can receive PDCCHs corresponding to multiple different QCL-TypeDs by applying the QCL-TypeD prioritization rule as in various embodiments such as alt 1 to alt 5 described above.

[0677] [Alt 6-1]

[0678] If a terminal reports to the base station that it is capable of simultaneously configuring signal reception for multiple TRPs based on multiple DCIs and reception of repeatedly transmitted PDCCHs, such as capability 3, it may not support reporting both capability 4 and capability 5. That is, the terminal may select and report either capability 4 or capability 5.

[0679] By allowing only one combination of capability 3 and capability 4 or capability 3 and capability 5 to be reported in this way, the base station can determine that even if the terminal supports capability 3, cases where different QCL-TypeDs are received in PDCCH repetition situations like capability 4 in multiple DCIs and multiple TRPs and cases where different QCL-TypeDs are received like capability 5 simultaneously do not occur. That is, the base station can use RRC configuration and / or MAC-CE message based on the capability reported by the terminal to instruct to receive control channels based on two QCL-type Ds in CORESETs that overlap in the time domain in multiple TRPs based on multiple DCIs, or to instruct to receive control channels based on two QCL-type Ds in PDCCHs that are repeatedly transmitted based on a single DCI.

[0680] [Alt 6-2]

[0681] If the terminal reports to the base station that it is capable of simultaneous configuration for signal reception of multiple TRPs based on multiple DCIs and reception of repeatedly transmitted PDCCHs, as in capability 3, the base station and / or the terminal may assume that capability 4 is not reported, regardless of capability 5 reporting.

[0682] That is, if the terminal reports that it can simultaneously receive multiple TRPs based on multiple DCIs and repeatedly transmitted PDCCHs, the terminal can receive PDCCH repetitions using a CORESET with the same CORESETPoolIndex set, and thus can consider that it can simultaneously receive PDCCHs repeatedly transmitted from a single TRP. Therefore, in this case, the terminal can reduce the data size or reduce the delay when reporting sequentially by omitting the report 4, which means that different QCL-TypeD reception is possible during PDCCH repetition.

[0683] [Alt 6-3]

[0684] If the terminal reports to the base station that it is capable of simultaneous configuration for reception of signals of multiple TRPs based on multiple DCIs and reception of repeatedly transmitted PDCCHs, such as capability 3, it can be assumed that the base station and / or the terminal do not report both 4 and 5.

[0685] That is, the terminal that reported the information related to capability 3 as described above can decide and control not to report all information related to capability 4 and capability 5, so as not to add the complexity caused by supporting simultaneous reception of different QCL-TypeDs to the scheduling complexity caused by supporting capability 3.

[0686] [Alt 6-4]

[0687] Instead of reporting to the base station that the terminal is capable of simultaneous configuration for signal reception of multiple TRPs based on multiple DCIs and reception of repeatedly transmitted PDCCHs, such as capability 3, the base station and / or terminal may directly report information related to capability 4 and / or capability 5. In other words, reporting capability 4 and / or capability 5 is a prerequisite, and reporting capability 3 may be unnecessary.

[0688] That is, since there is no case where information related to reception of multiple TRPs based on multiple DCIs and repeatedly transmitted PDCCHs is set simultaneously, it can be assumed that the base station and the terminal do not simultaneously receive different QCL-Type Ds in multiple TRP situations based on multiple DCIs and in different QCL-Type Ds in repeatedly transmitted PDCCH situations.

[0689] Therefore, the terminal can selectively receive and configure multiple TRPs based on multiple DCIs and / or repeatedly transmitted PDCCH reception-related information from the base station by reporting all information related to capability 4 and / or capability 5 without reporting capability 3 as a prerequisite.

[0690] FIG. 23 is a diagram illustrating an example of the operation of a terminal according to one embodiment of the present disclosure. Various modifications may be made to the method illustrated in the flowchart of FIG. 23. For example, although illustrated as a series of steps, the various steps in each drawing may overlap, occur in parallel, occur in different orders, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0691] In operation 2310, the terminal can receive, through upper layer signaling, (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for multiple CORESETs (control resource sets).

[0692] In operation 2320, the terminal may identify one or more CORESETs for PDCCH monitoring among the plurality of CORESETs based on a QCL (quasi co-location) Type-D configuration corresponding to the plurality of CORESETs when a CORESET pool index corresponding to some of the plurality of CORESETs is set to 1. According to one embodiment, one or more CORESETs for PDCCH monitoring may be identified among the plurality of CORESETs such that the number of QCL Type-D configurations for PDCCH monitoring is less than or equal to the maximum number of QCL Type-D configurations for PDCCH monitoring supported by the terminal based on a predefined QCL priority.

[0693] At operation 2330, the terminal may receive PDCCH repetitions based on PDCCH monitoring for one or more CORESETs.

[0694] For more specific details on the operation of the terminal described above, reference may be made to the description of various embodiments of the present disclosure described above.

[0695] FIG. 24 is a diagram illustrating an example of the operation of a base station according to one embodiment of the present disclosure. Various modifications may be made to the method illustrated in the flowchart of FIG. 24. For example, although illustrated as a series of steps, the various steps in each diagram may overlap, occur in parallel, occur in different orders, or occur multiple times. In other examples, steps may be omitted or replaced with other steps.

[0696] In operation 2410, the base station can transmit to the terminal (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for multiple CORESETs (control resource sets) through upper layer signaling.

[0697] In operation 2420, the base station may transmit a PDCCH repetition to the terminal based on one or more CORESETs among the plurality of CORESETs.

[0698] According to one embodiment, if a CORESET pool index corresponding to some of the plurality of CORESETs is 1, the one or more CORESETs may be based on a quasi co-location (QCL) type-D setting corresponding to the plurality of CORESETs and a predefined QCL priority.

[0699] According to one embodiment, the number of QCL Type-D configurations corresponding to one or more CORESETs may be less than or equal to the maximum number of QCL Type-D configurations for PDCCH monitoring supported by the terminal.

[0700] For more specific details on the operation of the above-described base station, reference may be made to the description of various embodiments of the present disclosure described above.

[0701] FIG. 25 is a diagram illustrating the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0702] Referring to FIG. 25, the terminal may include a transceiver, which refers to a terminal receiving unit (2500) and a terminal transmitting unit (2510), a memory (not shown), and a terminal processing unit (2505, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver units (2500, 2510), the memory, and the terminal processing unit (2505) of the terminal may operate. However, the components of the terminal are not limited to the examples described above. For example, the terminal may include more or fewer components than the components described above. In addition, the transceiver unit, the memory, and the processor may be implemented in the form of a single chip.

[0703] A transceiver unit can transmit and receive signals to and from a base station. The signals may include control information and data. To this end, the transceiver unit may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is merely one embodiment of the transceiver unit, and the components of the transceiver unit are not limited to the RF transmitter and RF receiver.

[0704] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit a signal output from the processor through the wireless channel.

[0705] Memory can store programs and data necessary for the terminal's operation. Furthermore, memory can store control information or data included in signals transmitted and received by the terminal. Memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0706] Additionally, the processor can control a series of processes to enable the terminal to operate according to the aforementioned embodiments. For example, the processor can receive DCI consisting of two layers and control components of the terminal to simultaneously receive multiple PDSCHs. There may be multiple processors, and the processors can perform component control operations of the terminal by executing programs stored in memory.

[0707] FIG. 26 is a diagram illustrating the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0708] Referring to FIG. 26, the base station may include a transceiver, which refers to a base station receiver (2600) and a base station transmitter (2610), a memory (not shown), and a base station processor (2605, or a base station control unit or processor). Depending on the communication method of the base station described above, the transceiver (2600, 2610), the memory, and the base station processor (2605) of the base station may operate. However, the components of the base station are not limited to the examples described above. For example, the base station may include more or fewer components than the components described above. In addition, the transceiver, the memory, and the processor may be implemented in the form of a single chip.

[0709] The transceiver can transmit and receive signals with the terminal. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0710] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit the signal output from the processor through the wireless channel.

[0711] The memory can store programs and data necessary for the operation of the base station. Furthermore, the memory can store control information or data included in signals transmitted and received by the base station. The memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0712] The processor can control a series of processes to enable the base station to operate according to the aforementioned embodiments of the present disclosure. For example, the processor can configure two layers of DCIs containing allocation information for multiple PDSCHs and control each component of the base station to transmit them. There may be multiple processors, and the processors can perform component control operations of the base station by executing programs stored in memory.

[0713] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0714] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. The one or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

[0715] These programs (software modules, software) may be stored in a random access memory, a non-volatile memory including a flash memory, a read only memory (ROM), an electrically erasable programmable read only memory (EEPROM), a magnetic disc storage device, a compact disc ROM (CD-ROM), a digital versatile disc (DVD) or other forms of optical storage, a magnetic cassette, or a memory formed by a combination of some or all of these. In addition, each configuration memory may include multiple copies.

[0716] Additionally, the program may be stored on an attachable storage device that is accessible via a communication network, such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device implementing an embodiment of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device implementing an embodiment of the present disclosure.

[0717] In the specific embodiments of the present disclosure described above, components included in the invention are expressed singularly or plurally, depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in plural may be composed of singular elements, or components expressed in singular may be composed of plural elements.

[0718] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are merely specific examples to easily explain the technical contents of the present disclosure and to help the understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art that other modified examples based on the technical idea of ​​the present disclosure are possible. In addition, each of the above embodiments can be combined and operated with each other as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment can be combined with each other to operate a base station and a terminal. For example, parts of the first embodiment and the second embodiment of the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above embodiments have been presented based on an FDD LTE system, other modified examples based on the technical idea of ​​the above embodiments can be implemented in other systems such as a TDD LTE system, 5G, or NR system.

[0719] Meanwhile, the order of description in the drawings explaining the method of the present disclosure does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

[0720] Alternatively, the drawings illustrating the method of the present disclosure may omit some components and include only some components without detracting from the essence of the present disclosure.

[0721] In addition, the method of the present disclosure may be implemented by combining some or all of the contents included in each embodiment within a scope that does not harm the essence of the invention.

[0722] Various embodiments of the present disclosure have been described above. The foregoing description of the present disclosure is for illustrative purposes only, and the embodiments of the present disclosure are not limited to the disclosed embodiments. Those skilled in the art will appreciate that the present disclosure can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present disclosure. The scope of the present disclosure is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present disclosure.

Claims

1. In a method performed by a terminal in a communication system, A step of receiving, through upper layer signaling, (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for multiple CORESETs (control resource sets); If the CORESET pool index corresponding to some of the above multiple CORESETs is set to 1: A step of identifying at least one CORESET for PDCCH monitoring among the plurality of CORESETs, such that the number of QCL Type-D configurations for PDCCH monitoring is less than or equal to the maximum number supported by the terminal, based on QCL (quasi co-location) Type-D configurations corresponding to the plurality of CORESETs and predefined QCL priorities; and A method comprising the step of receiving the PDCCH repetition based on PDCCH monitoring for the one or more CORESETs.

2. In paragraph 1, Among the above multiple CORESETs, the CORESET pool index corresponding to the remaining CORESETs excluding some of the above CORESETs is not set or is set to 0. When the above maximum number is defined per CORESET full index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the above maximum number is applied to each of the above some CORESETs and the remaining CORESETs. A method in which at least one CORESET is identified such that the number of QCL type-D settings is less than or equal to the maximum number, when the maximum number is defined for the entire CORESET full index, and is applied to the plurality of CORESETs.

3. In paragraph 1, The above multiple CORESETs overlap in the time domain, The above multiple CORESETs include multiple SS (search spaces), A method in which, in identifying the above QCL priority, the CORESET pool index is considered in ascending order, then the indices of the plurality of CORESETs are considered in ascending order, and then the indices of the plurality of SSs are considered in ascending order.

4. In paragraph 3, A method wherein two SSs having the same linking identifier are included in the above plurality of SSs, and a CORESET including a first SS among the two SSs is identified as being for the PDCCH monitoring, and a CORESET including a second SS among the two SSs is identified as being for the PDCCH monitoring.

5. In paragraph 3, A method wherein, when a first CORESET corresponding to a first CORESET pool index among the CORESET pool indices is identified as being for the PDCCH monitoring, a second CORESET corresponding to a second CORESET pool index among the CORESET pool indices and having a QCL Type-D setting that is the same as the QCL Type-D setting of the first CORESET is identified as being for the PDCCH monitoring.

6. In paragraph 3, A method in which the SS with the lowest index among the SSs included in the CORESET with the lowest index among the CORESET corresponding to the lowest CORESET full index among the above CORESET full indices is considered with the highest priority in identifying the QCL priority.

7. In paragraph 3, When information setting a high priority for a specific CORESET pool index is received, in identifying the QCL priority, the specific CORESET pool index set to the high priority is given priority instead of considering the CORESET pool indexes in ascending order. A method wherein, when information setting a high priority for a specific connection identifier is received, in identifying the QCL priority, two SSs having the specific connection identifier are given priority in identifying the QCL priority.

8. In paragraph 1, A method further comprising the step of transmitting a terminal capability report including information about the maximum number, wherein the terminal capability report further includes information corresponding to at least one feature group (FG) identified according to a predefined rule among a plurality of predefined FGs with respect to whether the terminal supports an operation of identifying one or more CORESETs for PDCCH monitoring based on the QCL priority.

9. At the terminal of the communication system, Transmitter and receiver; and comprising a processor connected to the transceiver; The above processor: Through higher layer signaling, (i) configuration for PDCCH (physical downlink control channel) repetition and (ii) configuration for multiple CORESETs (control resource sets) are received; If the CORESET pool index corresponding to some of the above multiple CORESETs is set to 1: Identifying at least one CORESET for PDCCH monitoring among the plurality of CORESETs such that the number of QCL Type-D configurations for PDCCH monitoring is less than or equal to the maximum number supported by the terminal, based on the QCL (quasi co-location) Type-D configurations corresponding to the plurality of CORESETs and predefined QCL priorities; and A terminal configured to receive the PDCCH repetition based on PDCCH monitoring for one or more of the CORESETs.

10. In paragraph 9, Among the above multiple CORESETs, the CORESET pool index corresponding to the remaining CORESETs excluding some of the above CORESETs is not set or is set to 0. When the above maximum number is defined per CORESET full index, the identification of one or more CORESETs such that the number of QCL type-D settings is less than or equal to the above maximum number is applied to each of the above some CORESETs and the remaining CORESETs. A terminal in which at least one CORESET is identified such that the number of QCL type-D settings is less than or equal to the maximum number, when the maximum number is defined for the entire CORESET pool index, and is applied to the plurality of CORESETs.

11. In paragraph 9, The above multiple CORESETs overlap in the time domain, The above multiple CORESETs include multiple SS (search spaces), A terminal in which, in identifying the above QCL priority, the CORESET pool index is considered in ascending order, then the indices of the plurality of CORESETs are considered in ascending order, and then the indices of the plurality of SSs are considered in ascending order.

12. In paragraph 11, If two SSs having the same linking identifier are included in the above plurality of SSs, and a CORESET including a first SS among the two SSs is identified as being for the PDCCH monitoring, a CORESET including a second SS among the two SSs is identified as being for the PDCCH monitoring; or If a first CORESET corresponding to a first CORESET pool index among the CORESET pool indices is identified as being for the PDCCH monitoring, a second CORESET corresponding to a second CORESET pool index among the CORESET pool indices and having a QCL type-D setting that is the same as the QCL type-D setting of the first CORESET is identified as being for the PDCCH monitoring; or Among the CORESET pool indices corresponding to the lowest CORESET pool index, the SS with the lowest index among the SSs included in the CORESET with the lowest index is considered with the highest priority in identifying the QCL priority; When information is received that sets a high priority for a specific CORESET pool index, in identifying the QCL priority, the specific CORESET pool index set to the high priority is given priority instead of considering the CORESET pool indexes in ascending order; or A terminal, wherein when information setting a high priority for a specific connection identifier is received, in identifying the QCL priority, two SSs having the specific connection identifier satisfy at least one of the things that are given priority in identifying the QCL priority.

13. In paragraph 9, The above processor is configured to transmit a terminal capability report including information about the maximum number; The terminal capability report further includes information corresponding to at least one feature group (FG) identified according to a predefined rule among a plurality of predefined FGs with respect to whether the terminal supports an operation of identifying one or more CORESETs for PDCCH monitoring based on the QCL priority.

14. In a method performed by a base station in a communication system, A step of transmitting to a terminal (i) a configuration for PDCCH (physical downlink control channel) repetition and (ii) a configuration for multiple CORESETs (control resource sets) through upper layer signaling; and A step of transmitting the PDCCH repetition to the terminal based on one or more CORESETs among the plurality of CORESETs, If the CORESET pool index corresponding to some of the above multiple CORESETs is 1, the one or more CORESETs are based on the QCL (quasi co-location) type-D setting corresponding to the multiple CORESETs and the predefined QCL priority, A method wherein the number of QCL type-D settings corresponding to one or more of the above CORESETs is less than or equal to the maximum number supported by the terminal.

15. In the base station of the communication system, Transmitter and receiver; and comprising a processor connected to the transceiver; The above processor: Transmitting to the terminal (i) settings for PDCCH (physical downlink control channel) repetition and (ii) settings for multiple CORESETs (control resource sets) through upper layer signaling; and is configured to transmit the PDCCH repetition to the terminal based on one or more CORESETs among the plurality of CORESETs; If the CORESET pool index corresponding to some of the above multiple CORESETs is 1, the one or more CORESETs are based on the QCL (quasi co-location) type-D setting corresponding to the multiple CORESETs and the predefined QCL priority, A base station, wherein the number of QCL type-D settings corresponding to one or more of the above CORESETs is less than or equal to the maximum number supported by the terminal.

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