Method and device for transmitting or receiving multiple pieces of data in a wireless cooperative communication system

Abstract

The present disclosure relates to a communication technology and a system thereof for integrating IoT technology and a quasi-fifth generation (5G) or 5G communication system that supports a higher data transmission rate than a 4th generation (4G) system (such as long term evolution (LTE)). The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technology (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, health care, digital education, retail business, safety and security-related services, etc.). According to various embodiments, a method and apparatus for sending or receiving multiple pieces of data in a wireless cooperative communication system can be provided.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and a method and device for transmitting or receiving a plurality of pieces of data in a wireless cooperative communication system. Background Art

[0002] In order to meet the increased demand for wireless data services since the deployment of 4G communication systems, efforts have been made to develop an improved 5G or quasi-5G communication system. Therefore, 5G or quasi-5G communication systems are also referred to as "super 4G networks" or "post-LTE systems". 5G communication systems are considered to be implemented at higher frequency (millimeter wave) bands (e.g., 60GHz bands) to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple input multiple output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antenna technology are discussed in 5G communication systems. In addition, in 5G communication systems, development of system network improvements is being carried out based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, collaborative communications, coordinated multipoint (CoMP), receiving end interference elimination, etc. In 5G systems, hybrid FSK with QAM modulation (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coded modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0003] The Internet, which is a human-centered connectivity network in which humans generate and consume information, has now evolved into the Internet of Things (IoT), in which distributed entities such as things exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is the product of the combination of IoT technology and big data processing technology through connection with cloud servers. Since IoT specific implementation requires technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology", sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. have recently been studied. Such IoT environments can provide smart Internet technology services that create new value for human life by collecting and analyzing data generated between connected things. IoT can be applied to a variety of fields, including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart appliances, and advanced medical services through the integration and combination between existing information technology (IT) and various industrial applications.

[0004] Therefore, various efforts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communications (MTC), and machine-to-machine (M2M) communications can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RANs) as an application of the above-mentioned big data processing technologies can also be considered as an example of the fusion of 5G technology and IoT technology.

[0005] With the advancement of wireless communication systems as described above, there is a need to provide a data transmission / reception scheme for cooperative communication.

[0006] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applied as prior art to the present disclosure. Summary of the invention

[0007] Technical issues

[0008] Based on the above discussion, the present disclosure provides a method and apparatus for transmitting or receiving one or more pieces of data between a transmission node and a terminal, so as to perform cooperative communication in a wireless communication system.

[0009] The technical subject matter pursued in the present disclosure may not be limited to the above-mentioned technical subject matter, and other technical subject matter not mentioned may be clearly understood by those skilled in the art to which the present disclosure relates through the following description.

[0010] Problem Solution

[0011] As an operation method of a base station in a wireless communication system, an embodiment proposes a method for transmitting a single transport block (TB) or multiple TBs, and a method for transmitting DCI information according to beam change of a base station to support joint transmission.

[0012] In order to solve the above problems, a method for processing a control signal in a wireless communication system disclosed in the present invention includes: receiving a first control signal sent from a base station; processing the received first control signal; and sending a second control signal generated based on the processing to the base station.

[0013] In order to solve the above problems, a terminal method disclosed in the present invention includes: receiving configuration information from a base station; receiving at least one of first control information or second control information from the base station based on the configuration information; determining a data receiving operation method through a first data channel or a second data channel based on at least one of a first time offset between a first data channel and a first control channel corresponding to the first control information or a second time offset between a second data channel and a second control channel corresponding to the second control information; and receiving data through the first data channel or the second data channel based on the determination result.

[0014] In order to solve the above problems, a terminal disclosed in the present invention includes a transceiver and a controller, which are configured to: receive configuration information from a base station; receive at least one of first control information or second control information from the base station based on the configuration information; determine a data receiving operation method through a first data channel or a second data channel based on at least one of a first time offset between a first data channel and a first control channel corresponding to the first control information or a second time offset between a second data channel and a second control channel corresponding to the second control information; and receive data through the first data channel or the second data channel based on the determination result.

[0015] Advantageous Effects of the Invention

[0016] According to an embodiment, in order to perform cooperative communication in a wireless communication system, a method and apparatus for transmitting or receiving one or more data between a transmission node and a terminal may be provided.

[0017] Effects obtainable from the present disclosure may not be limited to the above-mentioned effects, and other effects that are not mentioned may be clearly understood by those skilled in the art to which the present disclosure pertains through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts:

[0019] Figure 1 A time-frequency domain transmission structure of a long term evolution (LTE or Evolved Universal Terrestrial Radio Access (E-UTRA)) system, an LTE-A system, an NR system, or a wireless communication system similar thereto according to an embodiment is shown;

[0020] Figure 2 shows the structure of frames, subframes, and time slots in a 5th generation (5G) system according to an embodiment;

[0021] Figure 3 An example of a configuration of a bandwidth section in a wireless communication system according to an embodiment is shown;

[0022] Figure 4 An example of indication and switching of bandwidth portions in a wireless communication system according to an embodiment is shown;

[0023] Figure 5 An example of a control region configuration of a downlink control channel in a wireless communication system according to an embodiment is shown;

[0024] Figure 6An example of allocating physical downlink shared channel (PDSCH) frequency domain resources in a wireless communication system according to an embodiment is shown;

[0025] Figure 7 An example of allocating PDSCH time domain resources in a wireless communication system according to an embodiment is shown;

[0026] Figure 8 An example of allocating time domain resources according to subcarrier spacing of a control channel and a data channel in a wireless communication system according to an embodiment is shown;

[0027] Fig. 9 An example of cooperative communication antenna port configuration according to an embodiment is shown:

[0028] Fig.10 An example related to the configuration of a transmit configuration indication (TCI) state and a beamforming indication according to an embodiment is shown;

[0029] Fig.11 An example of cooperative communication based on a single PDCCH according to an embodiment is shown;

[0030] Fig.12 An example of cooperative communication based on multiple PDCCHs according to an embodiment is shown;

[0031] FIG. 13A shows an example of cooperative communication based on multiple PDCCHs according to another embodiment, and FIG. 13B shows an example of cooperative communication based on multiple PDCCHs according to another embodiment;

[0032] Fig.14 An example of cooperative communication based on a single PDCCH and multiple PDCCHs according to another embodiment is shown;

[0033] Fig.15 shows a structure of a terminal in a wireless communication system according to an embodiment; and

[0034] Fig.16 The structure of a base station in a wireless communication system according to an embodiment is shown. DETAILED DESCRIPTION

[0035] Invention Mode

[0036] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0037] In the process of describing the embodiments of the present disclosure, descriptions related to technical contents well-known in the art and not directly related to the present disclosure will be omitted. Such unnecessary descriptions are omitted to prevent the main idea of ​​the present disclosure from being obscured and to convey the main idea more clearly.

[0038] For the same reason, in the accompanying drawings, some elements may be exaggerated, omitted or schematically shown. In addition, the size of each element does not fully reflect the actual size. In the accompanying drawings, the same or corresponding elements have the same reference numerals.

[0039] By reference to the embodiments described in detail below in conjunction with the accompanying drawings, the advantages and characteristics of the present disclosure and their implementation will be apparent. However, the present disclosure is not limited to the embodiments set forth below, but can be implemented in various different forms. The following embodiments are provided only to fully disclose the present disclosure and inform those skilled in the art of the scope of the present disclosure, and the present disclosure is limited only by the scope of the attached claims. Throughout the entire specification, the same or similar reference numerals represent the same or similar elements.

[0040] Here, it should be understood that each frame of the flowchart diagram and the frame combination in the flowchart diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device create a device for implementing the functions specified in one or more flowchart frames. These computer program instructions can also be stored in a computer-available or computer-readable memory, which can instruct the computer or other programmable data processing device to operate in a particular manner, so that the instructions stored in the computer-available or computer-readable memory produce an article including an instruction device, which implements the functions specified in the one or more flowchart frames. Computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operating steps are performed on a computer or other programmable device, thereby generating a computer-implemented process, so that the instructions executed on a computer or other programmable device provide steps for implementing the functions specified in one or more flowchart frames.

[0041] In addition, each frame of the flowchart diagram can represent a module, a code segment or a code portion, which includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative embodiments, the functions described in the frame can occur out of order. For example, depending on the functionality involved, two frames shown in succession can actually be executed roughly at the same time, or these frames can sometimes be executed in reverse order.

[0042] As used herein, "unit" refers to a software element or hardware element that performs a predetermined function, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), which performs a predetermined function. However, "unit" does not always have the meaning of being limited to software or hardware. "Unit" can be constructed to be stored in an addressable storage medium or to execute one or more processors. Therefore, "unit" includes (for example) software element, object-oriented software element, class element or task element, process, function, attribute, program, subroutine, program code fragment, driver, firmware, microcode, circuit, data, database, data structure, table, array and parameter. The element and function provided by "unit" can be combined into a smaller number of elements or "units", or divided into a larger number of elements or "units". In addition, element and "unit" can be implemented as one or more CPUs in a reproduction device or a secure multimedia card. In addition, "unit" in an embodiment can include one or more processors.

[0043] Hereinafter, the operating principle of the present disclosure will be described in detail in conjunction with the accompanying drawings. In the following description of the present disclosure, when it may make the subject matter of the present disclosure quite unclear, the detailed description of the known functions or configurations combined herein will be omitted. The terms to be described below are terms defined in consideration of the functions in the present disclosure, and may differ according to the user, the user's intention or habit. Therefore, the definition of the terms should be determined based on the content throughout the entire specification. Hereinafter, a base station is a subject that performs resource allocation of a terminal, and may be at least one of a gNode B (gNB), an eNode B (eNB), a node B, a base station (BS), a radio access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a terminal, a cellular phone, a smart phone, a computer, or a multimedia system capable of performing a communication function, but is not limited thereto. Hereinafter, the present disclosure describes a technology for receiving broadcast information from a base station by a terminal in a wireless communication system. The present disclosure relates to a communication technology and a system thereof for a 5th generation (5G) communication system that integrates Internet of Things (IoT) technology and supports a higher data transmission rate than a 4th generation (4G) system (such as Long Term Evolution (LTE)) . The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail business, or safety and security-related services, etc.).

[0044] In the following description, for the sake of convenience, terms referring to broadcast information, terms referring to control information, terms associated with communication coverage, terms referring to state changes (e.g., events), terms referring to network entities, terms referring to messages, terms referring to device elements, etc. are exemplarily used. Therefore, the present disclosure is not limited to the terms used below, and other terms referring to subjects having equivalent technical meanings may be used.

[0045] In the following description, for ease of description, the present disclosure uses terms and names defined in the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE) standard. However, the present disclosure is not limited to these terms and names and can be applied to systems conforming to other standards in the same manner.

[0046] Wireless communication systems have expanded beyond their original role of providing voice-oriented services and have evolved into broadband wireless communication systems that provide high-speed, high-quality packet data services according to, for example, communication standards such as High Speed ​​Packet Access (HSPA), Long Term Evolution (LTE or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced (LTE-A), 3GPP's LTE-Pro, 3GPP2's High Rate Packet Data (HRPD) and Ultra Mobile Broadband (UMB), and IEEE's 802.16e. In addition, the communication standard of 5G or New Radio (NR) is being developed as a 5th generation wireless communication system.

[0047] As a representative example of a broadband wireless communication system, the LTE system adopts an orthogonal frequency division multiplexing (OFDM) scheme in the downlink (DL) and a single carrier frequency division multiple access (SC-FDMA) in the uplink (UL). The uplink indicates a wireless link for sending data or control signals from a terminal (user equipment (UE) or mobile station (MS)) to a base station (eNode B or base station (BS)), and the downlink indicates a wireless link for sending data or control signals from a base station to a terminal. In the above-mentioned multiple access scheme, generally, data or control information is distinguished according to users by allocating or managing time-frequency resources for carrying data or control information of each user, wherein the time-frequency resources do not overlap, that is, orthogonality is established.

[0048] As the next generation communication system beyond LTE, that is, the 5G communication system needs to support services that meet various needs so as to freely adapt to various needs of users and service providers. The services considered by the 5G system may be enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable low latency communication (URLLC), etc.

[0049] According to some embodiments, eMBB is intended to provide a more enhanced data rate than the data rate supported by conventional LTE, LTE-A or LTE-Pro. For example, in a 5G communication system, from the perspective of a single base station, eMBB needs to provide a peak data rate of 20Gbps for DL ​​and a peak data rate of 10Gbps for uplink. In addition, the 5G communication system needs to provide an increased user-perceived data rate of the terminal. In order to meet these needs, it is necessary to improve various transmission / reception technologies, including more enhanced multiple-input multiple-output (MIMO) transmission technology. In addition, the data rate required in the 5G communication system is met by using a frequency bandwidth wider than 20MHz in a frequency band of 3-6GHz or 6GHz or higher (rather than the 2GHz frequency band used in the current LTE system).

[0050] In addition, in order to support application services, such as the Internet of Things (IoT) in the 5G system, mMTC is considered. mMTC may require large terminal access support in the cell, improved terminal coverage, enhanced battery time, and reduced terminal costs in order to effectively provide IoT. In IoT, since the terminal is attached to various sensors and devices to provide communication functions, IoT needs to support a large number of terminals in the cell (e.g., 1,000,000 terminals / km2). In addition, considering the characteristics of the service, the terminal supporting mMTC may be located in a shadow area that the cell may not cover, such as the basement of a building, and may require a wider coverage than other services provided by the 5G system. Terminals supporting mMTC may require low-cost terminals, and may require very long battery life in mMTC because it is difficult to frequently replace the battery of the terminal.

[0051] Finally, URLLC is a cellular-based wireless communication service for mission-critical purposes, such as remote control of robots or mechanical devices, industrial automation, drones, remote health care, emergency notifications, etc., and requires ultra-low latency and ultra-high reliability communications. For example, a service supporting URLLC may need to meet an air interface latency of less than 0.5 milliseconds and also have a 10 -5 Or smaller packet error rate requirements. Therefore, for services supporting URLLC, the 5G system needs to provide a smaller transmission time interval (TTI) than other services, and also needs to allocate wider resources in the frequency band. However, the above-mentioned mMTC, URLLC and eMBB are only examples of different service types, and the service types to be applied according to the present disclosure are not limited to the above examples.

[0052] The services considered in the above-mentioned 5G communication system need to be multiplexed and provided on a single framework basis. That is, for efficient resource management and control, services can be controlled and transmitted after being integrated into a single system, rather than operating independently.

[0053] In the following, the embodiments of the present disclosure are described by taking LTE, LTE-A, LTE Pro or NR systems as examples, but the embodiments of the present disclosure can be applied to other communication systems with similar technical backgrounds or channel forms. In addition, by the judgment of ordinary technicians in this field, without significantly departing from the scope of the present disclosure, the embodiments of the present disclosure can be applied to other communication systems through some modifications within the scope.

[0054] The present disclosure relates to a method and apparatus for repeatedly transmitting data and control signals between a terminal and a plurality of transmission nodes performing cooperative communication to enhance communication reliability.

[0055] According to the present disclosure, when network cooperative communication is used in a wireless communication system, the reliability of data / control signal reception of a terminal can be enhanced.

[0056] Hereinafter, the framework structure of the 5G system will be described in more detail with reference to the accompanying drawings.

[0057] Figure 1 The time-frequency domain transmission structure of an LTE system, an LTE-A system, an NR system, or a wireless communication system similar thereto according to an embodiment is shown.

[0058] Figure 1 The basic structure of the time-frequency domain is shown. The time-frequency domain is the wireless resource area for sending data or control channels in the 5G system. Figure 1 ,exist Figure 1 In the time-frequency domain, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of resources in the time-frequency domain is a resource element (RE) 1-01, and can be defined as 1 orthogonal frequency division multiplexing (OFDM) symbol 1-02 on the time axis and 1 subcarrier 1-03 on the frequency axis. In the frequency domain, (For example, 12) consecutive REs may constitute one resource block (RB) 1-04.

[0059] Figure 2 The structure of frames, subframes, and time slots in a 5G system according to an embodiment is shown.

[0060] Figure 2 The time slot structure considered in the 5G system is shown. Figure 2 ,exist Figure 2An example of the structure of a frame 2-00, a subframe 2-01, and a time slot 2-02 is shown in FIG. The length of one frame 2-00 may be defined as 10Ms. The length of one subframe 2-01 may be defined as 1ms. Therefore, a total of 10 subframes 2-01 may constitute one frame 2-00. One time slot 2-02 or 2-03 may be defined as 14 OFDM symbols (i.e., the number of symbols per time slot). ). One time slot or multiple time slots 2-02 or 2-03 may constitute one subframe 2-01. Depending on the configured value μ2-04 or 2-05 of the subcarrier spacing, the number of time slots 2-02 or 2-03 per subframe 2-01 may be different. Figure 2 In the example of FIG. 1 , for the subcarrier spacing configuration value, the case where μ=0 (2-04) and the case where μ=1 (2-05) are shown. In the case where μ=0 (2-04), one time slot 2-02 can constitute one subframe 2-01. In the case where μ=0 (2-05), two time slots 2-03 can constitute one subframe 2-01. That is, depending on the subcarrier spacing configuration value μ, the number of time slots in one subframe can be different, and therefore, the number of time slots in a frame Can be different. According to each subcarrier spacing configuration μ and It can be defined in the following [Table 1].

[0061] [Table 1]

[0062]

[0063] In NR, up to 250 or more RBs can constitute one component carrier (CC) or serving cell. Therefore, when the terminal always receives the entire serving cell bandwidth as in the case of LTE, the terminal may consume excessive power. In order to overcome the excessive consumption of power, the base station can configure one or more bandwidth parts (BWP) for the terminal and support the terminal so that the terminal can change the reception area in the cell. In NR, the base station can configure the "initial BWP" for the terminal through the master information block (MIB), that is, the bandwidth of CORESET#0 (or common search space, (CSS)). In the following, the base station can configure the initial BWP (first BWP) of the terminal via RRC signaling, and notify at least one BWP configuration information that can be indicated later via downlink control information (DCI). Later, the base station can indicate to the terminal which bandwidth the terminal is to use by notifying the BWP ID via DCI. If the terminal fails to receive DCI at the currently allocated BWP for a specific time or longer, the terminal can try to receive DCI by returning to the "default BWP".

[0064] Figure 3An example of the configuration of a bandwidth section in a wireless communication system according to an embodiment is shown.

[0065] Figure 3 An example of the configuration of a bandwidth part in a 5G communication system is shown. Figure 3 , shows an example showing that the terminal bandwidth 3-00 is configured as two bandwidth parts, namely bandwidth part #1 (BWP#1) 3-05 and bandwidth part #2 (BWP#2) 3-10. The base station can configure one bandwidth part or multiple bandwidth parts for the terminal, and configure the information shown in the following [Table 2] for each bandwidth part.

[0066] [Table 2]

[0067]

[0068] In addition to the configuration information described in [Table 2] above, various parameters related to the bandwidth part may be configured for the terminal. The above information may be transmitted to the terminal by the base station via higher layer signaling, such as RRC signaling. The configured bandwidth part or at least one of the configured multiple bandwidth parts may be activated. Whether to activate the configured bandwidth part may be transmitted to the terminal by the base station semi-statically via RRC signaling or dynamically via a medium access control (MAC) control element (CE) or DCI.

[0069] The above configuration of the bandwidth portion supported in the 5G communication system can be used for various purposes.

[0070] In one example, when the bandwidth supported by the terminal has a smaller value than the system bandwidth, the bandwidth supported by the terminal can be supported. For example, in [Table 2], when the frequency position of the bandwidth part is configured for the terminal (configuration information 2), the terminal can send or receive data at a specific frequency position in the system bandwidth.

[0071] In another example, in order to support different digital systems, the base station can configure multiple bandwidth parts for the terminal. For example, in order to support data transmission or reception to a predetermined terminal using not only a subcarrier spacing of 15kHz but also a subcarrier spacing of 30kHz, two bandwidth parts can be configured to use a subcarrier spacing of 15kHz and a subcarrier spacing of 30kHz, respectively. The different bandwidth parts can be frequency division multiplexed (FDM), and when sending or receiving data at a specific subcarrier spacing, the bandwidth part configured as the corresponding subcarrier spacing can be activated.

[0072] In another example, in order to reduce the power consumption of the terminal, the base station can configure bandwidth parts with different sizes of bandwidth for the terminal. For example, when the terminal supports a bandwidth with a very large value, such as a bandwidth of 100 MHz, and always uses the corresponding bandwidth to send or receive data, a very large amount of power may be consumed. In particular, in the absence of business, from the perspective of power consumption, the unnecessary monitoring of the downlink control channel of the 100 MHz bandwidth by the terminal may be considered inefficient. Therefore, in order to reduce the power consumption of the terminal, the base station can configure a bandwidth part with a relatively small value, such as a bandwidth part of 20 MHz, for the terminal. In the absence of business, the terminal can perform monitoring using the 20 MHz bandwidth part, and the terminal can send or receive data using the 100 MHz bandwidth part according to the instructions of the base station.

[0073] Figure 4 An example of indication and switching of bandwidth portions in a wireless communication system according to an embodiment is shown.

[0074] Figure 4 The method for dynamically changing the bandwidth configuration is shown. Figure 4 As shown in [Table 2], the base station can configure one bandwidth part or multiple bandwidth parts for the terminal, and through the configuration of each bandwidth part, inform the terminal of information about the bandwidth of the bandwidth part, the frequency position of the bandwidth part, the numerology of the bandwidth part, etc. Figure 4 In FIG. 4 , an example is shown in which two bandwidth parts in the terminal bandwidth 4-00 are configured for a terminal, namely, bandwidth part #1 (BWP#1) 4-05 and bandwidth part #2 (BWP#2) 4-10. In the configured bandwidth parts, one bandwidth part or multiple bandwidth parts can be activated. Figure 4 In FIG. 5 , an example showing activation of one bandwidth portion may be considered. Figure 4 It is shown that bandwidth part #1 (BWP#1) 4-05 in the bandwidth part configured in time slot #0 (4-25) is activated, and the terminal can monitor the physical downlink control channel (PDCCH) in the control region #1 (4-45) configured for bandwidth part #1 (BWP#1) 4-05, and can send or receive data 4-55 in bandwidth part #1 (BWP#1) 4-05. Depending on the activated bandwidth part in the configured bandwidth part, the control region in which the terminal receives the PDCCH may be different, and therefore the bandwidth of the terminal monitoring the PDCCH may be different.

[0075] The base station may additionally send an indicator to the terminal for switching the configuration of the bandwidth part. Here, the switching of the configuration bandwidth part may be considered to be the same as the operation of activating a specific bandwidth part (for example, changing the activation from bandwidth part A to bandwidth part B). The base station may send a configuration switching indication to the terminal in a specific time slot. After receiving the configuration switching indication from the base station, the terminal may apply the configuration switched according to the configuration switching indication from a specific time point, determine the bandwidth part to be activated, and monitor the PDCCH in the control area configured for the activated bandwidth part.

[0076] exist Figure 4 In the example, the base station may send a configuration switching indication 4-15 to the terminal in the time slot #1 4-30, which indicates that the activated bandwidth part is switched from the existing bandwidth part #1 (BWP#1) 4-05 to the bandwidth part #2 (BWP#2) 4-10. After receiving the corresponding indication, the terminal may activate the bandwidth part #2 (BWP#2) 4-10 according to the details of the indication. In this case, a conversion time 4-20 for switching the bandwidth part may be required, and thus the time point of switching and applying the bandwidth part to be activated may be determined. Figure 4 A case where a switching time 4-20 corresponding to one time slot is adopted after receiving a configuration switching indication 4-15 is shown. During the transmission time 4-20, data transmission or reception may not be performed 4-60. Therefore, in time slot #2 (4-35), bandwidth part #2 (BWP #2) 4-10 may be activated and the corresponding bandwidth part may be used to perform operations of transmitting or receiving a control channel or data.

[0077] The base station may pre-configure one bandwidth part or multiple bandwidth parts via high-layer signaling (e.g., RRC signaling, etc.), and may indicate activation according to a method in which the configuration switching indication 4-15 is mapped to one of the bandwidth part configurations pre-configured by the base station. 2 The N-bit indication can select and indicate one of the N pre-configured bandwidth parts. An example of using a 2-bit indication to indicate configuration information about a bandwidth part is shown in the following [Table 3].

[0078] [Table 3]

[0079]

[0080]

[0081] Figure 4 The configuration switching indication 4-15 of the bandwidth part shown in the figure can be transmitted from the base station to the terminal in the form of MAC CE signaling or L1 signaling (for example, common DCI, group common DCI, terminal-specific DCI, etc.). Figure 4The configuration switching indication 4-15 shown indicates the time point at which the bandwidth portion activation is started to be applied. The time point at which the continued switching is applied may be determined according to a predefined value (for example, once the configuration switching indication is received, the configuration switching is applied after N (≥1) time slots), which may be configured for the terminal by the base station via higher layer signaling (for example, RRC signaling), or may be partially included in the details of the configuration switching indication 4-15 and sent. Alternatively, the time point at which the continuous switching is applied may be determined according to a combination of the above schemes. After receiving the configuration switching indication 4-15 for the bandwidth portion, the terminal may start applying the switching configuration from the time point at which the indication is obtained according to the above scheme.

[0082] Hereinafter, a downlink control channel in a 5G communication system will be described in more detail with reference to the accompanying drawings.

[0083] Figure 5 An example of a control region configuration of a downlink control channel in a wireless communication system according to an embodiment is shown.

[0084] Figure 5 An example of a control region (control resource set (CORESET)) for transmitting a downlink control channel in a 5G wireless communication system is shown. Figure 5 ,exist Figure 5 An example is shown in which a terminal bandwidth part 5-10 is configured on the frequency axis, and two control resource sets (control resource set #1 (CORESET#1) 5-01 and control resource set #2 (CORESET#2) 5-02) are configured in a time slot 5-20 on the time axis. The control resource sets 5-01 and 5-02 can be configured for specific frequency resources 5-03 within the entire terminal bandwidth part 5-10 on the frequency axis. The control resource sets 5-01 and 5-02 can be configured as one OFDM symbol or multiple OFDM symbols on the time axis, and can be defined as a control region duration (control resource set duration) 5-04. Figure 5 In the example of , control resource set #1 (5-01) is configured as a control resource set duration of two symbols, and control resource set #2 (5-02) is configured as a control resource set duration of one symbol.

[0085] The above-mentioned control region in the 5G system can be configured for the terminal by the base station via higher layer signaling (e.g., system information, master information block (MIB) and radio resource control signaling). Configuring the control region for the terminal may indicate providing an identifier of the control region for the terminal, a frequency position of the control region, a symbol duration of the control region, etc. For example, the information shown in [Table 4] may be included.

[0086] [Table 4]

[0087]

[0088] In [Table 4], the tci-StatesPDCCH (abbreviated as "TCI state") configuration information may include information on the index of one or more synchronization signal (SS) / physical broadcast channel (PBCH) blocks or a channel state information reference signal (CSI-RS) that is in a quasi-co-site (QCL) relationship with a demodulation reference signal sent in the corresponding control region.

[0089] In the following, a method for allocating time and frequency resources for data transmission in an NR system is described.

[0090] In the NR system, in addition to the frequency domain resource candidate allocation indicated by the BWP, a frequency domain resource allocation (FD-RA) method may be provided in detail as follows.

[0091] Figure 6 An example of PDSCH frequency domain resource allocation in a wireless communication system according to an embodiment is shown.

[0092] Figure 6 Three frequency domain resource allocation methods of Type 0 (6-00), Type 1 (6-05) and dynamic switching 6-10 are shown, which can be configured via higher layer signaling in the NR system.

[0093] refer to Figure 6 In the case where the terminal is configured to use only resource type 0 (6-00) via higher layer signaling, the partial segment of downlink control information (DCI) that allocates PDSCH to the corresponding terminal may have N RBG The conditions under which this is the case will be described again later. Here, N RBG It means the number of resource block groups (RBGs) determined according to the BWP size allocated by the BWP indicator and the higher layer parameter rbg size, as shown in [Table 5] below, and data is transmitted to the RBG indicated by 1 according to the bitmap.

[0094] [Table 5]

[0095] Bandwidth portion size Configuration 1 Configuration 2 1-36 2 4 37-72 4 8 73-144 8 16 145-275 16 16

[0096] In the case where the terminal is configured to use only resource type 1 (6-05) via higher layer signaling, the partial segment of the DCI that allocates the PDSCH to the corresponding terminal may have a The conditions satisfying this situation will be described again later. The base station may configure the starting VRB 6-20 and the frequency domain resource length 6-25 that are continuously allocated from the starting VRB 6-20.

[0097] In the case where the terminal is configured to use resource type 0 and resource type 1 (6-10) via higher layer signaling, a partial fragment of the DCI that allocates the PDSCH to the corresponding terminal may have frequency domain resource allocation information, which includes a bit with a larger value 6-35 between the payload 6-15 for configuring resource type 0 and the payload 6-20 or 6-25 for configuring resource type 1. The conditions for satisfying this situation will be described again later. Here, a bit may be added to the most significant bit (MSB) of the frequency domain resource allocation information in the DCI, which may indicate the use of resource type 0 when the corresponding bit is 0, and may indicate the use of resource type 1 when the corresponding bit is 1.

[0098] Figure 7 An example of physical downlink shared channel (PDSCH) time domain resource allocation in a wireless communication system according to an embodiment is shown.

[0099] Figure 7 An example of time domain resource allocation in an NR system is shown. Figure 7 The base station can indicate the time domain position of the PDSCH resource according to the starting position 7-00 and length 7-05 of the OFDM symbol in a time slot. These positions are configured by the DCI of the data channel and control channel via higher layer signaling, the scheduling offset (K 0 ) value and subcarrier spacing (ScS) (μ PDSCH and μ PDCCH ) to indicate dynamically.

[0100] Figure 8 An example of allocating time domain resources according to subcarrier spacings of a control channel and a data channel in a wireless communication system according to an embodiment is shown.

[0101] refer to Figure 8 , the subcarrier spacing of the data channel is the same as the subcarrier spacing of the control channel (μ PDSCH =μ PDCCH )8-00, since the time slot number of the data channel is the same as the time slot number of the control channel, the base station and the terminal can know that according to the predetermined time slot offset K 0 At the same time, the subcarrier spacing of the data channel is different from that of the control channel (μ PDSCH ≠μ PDCCH )8-05, since the time slot number of the data channel is different from the time slot number of the control channel, the base station and the terminal can know the subcarrier spacing of the reference PDCCH and offset K according to the predetermined time slot. 0 The scheduling offset that occurred.

[0102] In the NR system, in order to effectively receive the control channel of the terminal, various types of DCI formats are provided as shown in [Table 6] below.

[0103] [Table 6]

[0104]

[0105]

[0106] For example, in order to allocate (schedule) a PDSCH to one cell, the base station may use DCI format 0_0 or DCI format 0_1.

[0107] When DCI format 0_1 ​​is transmitted together with a CRC scrambled by a cell radio network temporary identifier (C-RNTI), a configured scheduling RNTI (CS-RNTI), or a new RNTI, DCI format 0_1 ​​may include at least the following pieces of information:

[0108] - Identifier of DCI format (1 bit): This indicates the DCI format identifier and is always configured to 1.

[0109] - Frequency domain resource allocation (N RBG bit or bit: This indicates the frequency domain resource allocation. If DCI format 1_0 is monitored in the UE-specific search space, then is the size of the active DL BWP. Otherwise, is the size of the initial DL BWP. N RBG Corresponding to the resource block group number. For a more detailed scheme, refer to the above frequency domain resource allocation.

[0110] - Time domain resource allocation (0-4 bits): This indicates the time domain resource allocation according to the above description.

[0111] - VRB to PRB mapping (1 bit): In case of 0, this indicates non-interleaved VRP to PRB mapping, and in case of 1, this indicates interleaved VRP to PRB mapping.

[0112] - Modulation and coding scheme (5 bits): This indicates the modulation order and coding rate used for PDSCH transmission.

[0113] - New Data Indicator (1 bit): This indicates whether the PDSCH is an initial transmission or a retransmission, depending on whether it is switched.

[0114] - Redundancy version (2 bits): This indicates the redundancy version used for PDSCH transmission.

[0115] - HARQ process number (4 bits): This indicates the HARQ process number used for PDSCH transmission.

[0116] - Downlink Allocation Index (2 bits): DAI indicator

[0117] - TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator

[0118] - PUCCH resource indicator (3 bits): This is a PUCCH resource indicator and indicates one of eight resources configured via higher layer signaling.

[0119] - PDSCH to HARQ_Feedback Timing Indicator (3 bits): This is the HARQ feedback timing indicator and indicates one of eight feedback timing offsets configured via higher layer signaling.

[0120] When DCI format 1_1 is transmitted together with a CRC scrambled by a cell radio network temporary identifier (C-RNTI), a configured scheduling RNTI (CS-RNTI), or a new RNTI, DCI format 1_1 may include at least the following pieces of information:

[0121] - Identifier of DCI format (1 bit): This indicates the DCI format identifier and is always configured to 1.

[0122] - Carrier indicator (0 or 3 bits): This indicates the CC (or cell) in which the PDSCH allocated by the corresponding DCI is transmitted.

[0123] - Bandwidth part indicator (0, 1 or 2 bits): This indicates the BWP in which the PDSCH allocated by the corresponding DCI is transmitted.

[0124] - Frequency Domain Resource Allocation (determined by the Frequency Domain Resource Allocation payload): This indicates the frequency domain resource allocation and is the size of the active DL BWP. For a more detailed scheme, refer to the above frequency domain resource allocation.

[0125] - Time domain resource allocation (0-4 bits): This indicates the time domain resource allocation according to the above description.

[0126] - VRB to PRB mapping (0 or 1 bit): In case of 0, this indicates non-interleaved VRP to PRB mapping, and in case of 1, this indicates interleaved VRP to PRB mapping. This is 0 bit when frequency domain resource allocation is configured as resource type 0.

[0127] -PRB bundling size indicator (0 or 1 bit): This is a 0 bit when the higher layer parameter prb-BundlingType is not configured or configured as "static". This is a 1 bit when the higher layer parameter prb-BundlingType is configured as "dynamic".

[0128] - Rate matching indicator (0, 1 or 2 bits): This indicates the rate matching mode.

[0129] - ZP CSI-RS trigger (0, 1 or 2 bits): This is an indicator to trigger aperiodic ZP CSI-RS.

[0130] -For transport block 1:

[0131] - Modulation and coding scheme (5 bits): This indicates the modulation order and coding rate used for PDSCH transmission.

[0132] - New Data Indicator (1 bit): This indicates whether the PDSCH is an initial transmission or a retransmission, depending on whether it is switched.

[0133] - Redundancy version (2 bits): This indicates the redundancy version used for PDSCH transmission.

[0134] -For transport block 2:

[0135] - Modulation and coding scheme (5 bits): This indicates the modulation order and coding rate used for PDSCH transmission.

[0136] - New Data Indicator (1 bit): This indicates whether the PDSCH is an initial transmission or a retransmission, depending on whether it is switched.

[0137] - Redundancy version (2 bits): This indicates the redundancy version used for PDSCH transmission.

[0138] - HARQ process number (4 bits): This indicates the HARQ process number used for PDSCH transmission.

[0139] - Downlink Allocation Index (0, 2 or 4 bits): DAI indicator

[0140] - TPC command for scheduled PUCCH (2 bits): PUCCH power control indicator

[0141] - PUCCH resource indicator (3 bits): This is a PUCCH resource indicator and indicates one of eight resources configured via higher layer signaling.

[0142] - PDSCH to HARQ_Feedback Timing Indicator (3 bits): This is the HARQ feedback timing indicator and indicates one of eight feedback timing offsets configured via higher layer signaling.

[0143] - Antenna port (4, 5 or 6 bits): This indicates the DMRS port and CDM group with no data.

[0144] - Send configuration indicator (0 or 3 bits): TCI indicator

[0145] -SRS request (2 or 3 bits): SRS transmission request indicator

[0146] -CBG transmission information (0, 2, 4, 6 or 8 bits): This is an indicator indicating whether the code block group in the allocated PDSCH is transmitted. 0 means that the corresponding CBG is not transmitted and 1 means that the corresponding CBG is transmitted.

[0147] -CBG flush (0 or 1 bit): This is an indicator whether the previous CBG is contaminated. 0 means that the previous CBG may be contaminated, and 1 means that the previous CBG can be used when receiving a retransmission (combinable).

[0148] -DMRS sequence initialization (0 or 1 bit): DMRS scrambling ID selection indicator

[0149] The number of DCI fragments with different sizes that the terminal can receive for each time slot in the corresponding cell is at most 4. The number of DCI fragments with different sizes and scrambled by C-RNTI that the terminal can receive for each time slot in the corresponding cell is at most 3.

[0150] Here, the antenna port indication may be indicated as shown in [Table 7] to [Table 10] below.

[0151] [Table 7]

[0152] Antenna port (1000 + DMRS port), dmrs-Type = 1, maxLength = 1

[0153]

[0154]

[0155] [Table 8]

[0156] Antenna port (1000+DMRS port), dmrs-Type=1, maximum length=2

[0157]

[0158]

[0159]

[0160] [Table 9]

[0161] Antenna port (1000 + DMRS port), dmrs-Type = 2, maxLength = 1

[0162]

[0163]

[0164] [Table 10]

[0165] Antenna port (1000 + DMRS port), DMRS-Type = 2, maximum length = 2

[0166]

[0167]

[0168]

[0169] [Table 7] is a table that can be used when the dmrs-Type is indicated as 1 and the maximum length is indicated as 1. [Table 8] is a table that can be used when the dmrs-Type is indicated as 1 and the maximum length is indicated as 2. When the dmrs-Type is 2 and the maximum length is 1, [Table 9] is used to indicate the DMRS port being used, and when the dmrs-Type is 2 and the maximum length is 2, [Table 10] is used to indicate the port. The numbers 1, 2, and 3 indicated by the "Number of DMRS CDM groups without data" in [Table 7] to [Table 10] mean CDMRS groups {0}, {0, 1}, and {0, 1, 2}, respectively. The DMRS port indicates the index of the port being used at the timing position. The antenna port is indicated as DMRS+1000. The CDM group of DMRS is connected to the scheme and antenna port for generating the DMRS sequence, as shown in [Table 11] and [Table 12]. [Table 11] shows parameters for the case of using dmrs-Type=1, and [Table 12] shows parameters for the case of using dmrs-Type=2.

[0170] [Table 11]

[0171] Parameters of PDSCH DMRS dmrs-Type=1.

[0172]

[0173] [Table 12]

[0174] Parameters of PDSCH DMRS dmrs-Type=2.

[0175]

[0176] The DMRS sequence according to each parameter is determined by the following [Equation 1].

[0177] [Equation 1]

[0178]

[0179]

[0180] k′=0,1

[0181]

[0182] n=0,1,...

[0183] In [Table 7] and [Table 8], when only one codeword is enabled, rows 2, 9, 10, 11, and 30 are used only for single-user MIMO. That is, in this case, the terminal may not assume that another terminal is co-scheduled, and may not perform multiple-user MIMO reception operations such as canceling, nulling, or whitening multiple-user interference operations.

[0184] In [Table 9] and [Table 10], when only one codeword is enabled, rows 2, 10, and 23 are used only for single-user MIMO. That is, in this case, the terminal may not assume that another terminal is co-scheduled, and may not perform multiple-user MIMO reception operations such as canceling, nulling, or whitening multiple-user interference operations.

[0185] Fig. 9 An example of a cooperative communication antenna port configuration according to an embodiment is shown.

[0186] refer to Fig. 9 , shows an example of allocating transmit-receive-point (TRP)-specific radio resources according to a joint transmission (JT) technique and scenario.

[0187] exist Fig. 9 In FIG. 9-00 , coherent joint transmission (C-JT) supporting interferometric coding between cells, TRPs or / and beams is shown.

[0188] In C-JP, transmit reception point (TRP) A 9-05 and TRP B 9-10 transmit the same data (PDSCH), and joint precoding is performed in multiple TRPs. This may mean that TRP A 9-05 and TRP B 9-10 transmit the same DMRS port (for example, both TRPs transmit DMRS ports A and B) for the same PDSCH transmission. In this case, the terminal can receive a DCI information for receiving a PDSCH demodulated based on the DMRS transmitted through DMRS ports A and B.

[0189] exist Fig. 99-20 shows non-coherent joint transmission (NC-JT) that supports non-coherent precoding between cells, TRPs or / and beams. In the case of NC-JT, cells, TRPs and / or beams transmit different PDSCHs, and separate precoding can be applied for each PDSCH. This may mean that TRP A 9-25 and TRP B 9-30 transmit different DMRS ports (for example, TRP A transmits DMRS port A and TRP B transmits DMRS port B) for different PDSCH transmissions. In this case, the terminal can receive two types of DCI information for receiving PDSCH A demodulated based on the DMRS sent through DMRS port A and PDSCH B demodulated based on the DMRS sent through DMRS port B.

[0190] In order to support NC-JT to provide data to one terminal from two or more transmission points at the same time, it is necessary to allocate PDSCH sent from two or more different transmission points through one PDCCH, or it is necessary to allocate PDSCH sent from two or more different transmission points through multiple PDCCHs. The terminal obtains the quasi-co-location (QCL) connection relationship between the reference signal or channel based on L1 / L2 / L3 signaling, and can effectively estimate the large-scale parameters of the reference signal or channel through this relationship. When the transmission points of the reference signal or channel are different, the large-scale parameters are difficult to share with each other. Therefore, when performing collaborative transmission, the base station needs to notify the terminal of the quasi-co-location information about two or more transmission points through two or more TCI states at the same time. When non-coherent joint transmission is supported by multiple PDCCHs, that is, when two or more PDCCHs allocate two or more PDSCHs to the same service cell and the same bandwidth part at the same time, each of the two or more TCI states can be allocated to the corresponding PDSCH or the corresponding DMRS port through the corresponding PDCCH. At the same time, when non-coherent joint transmission is supported through a single PDCCH, that is, when one PDCCH allocates two or more PDSCHs to the same service cell and the same bandwidth part at the same time point, each of the two or more TCI states needs to be allocated to the corresponding PDSCH or the corresponding DMRS port through one PDCCH.

[0191] When it is assumed that the DMRS ports allocated to the terminal at a specific time point are divided into a DMRS port group A transmitted from a transmission point A and a DMRS port group B transmitted from a transmission point B, two or more TCI states are respectively connected to the DMRS port groups, and thus channel estimation can be performed based on different QCL assumptions for each group. At the same time, in order to improve the channel measurement accuracy and also reduce the transmission burden, different DMRS ports can be code division multiplexed (CDM), frequency division multiplexed (FDM) or time domain multiplexed (TDM). Among them, the DMRS ports of code division multiplexing are generally referred to as CDM groups. Since code-based multiplexing operates smoothly for the DMRS ports in the CDM group when the channel properties of the ports are similar (that is, since the DMRS ports in the CDM group are well distinguished by orthogonal cover codes (OCC) when the channel properties of the ports are similar), it is important for the DMRS ports present in the same CDM group not to have different TCI states. The present disclosure provides a method for indicating to a terminal a DMRS port and a CDM group that there is no data that satisfies the attribute.

[0192] Meanwhile, in the present disclosure, for convenience of description, an operation of transmitting control information through a PDCCH may be described as an operation of transmitting a PDDCH, and an operation of transmitting data through a PDSCH may be described as an operation of transmitting a PDSCH.

[0193] Hereinafter, for the convenience of description, [Table 7] to [Table 12] are referred to as "first antenna port indication (or conventional antenna port indication)", and the table partially or completely modified from the code points of [Table 7] to [Table 12] is referred to as "second antenna port indication (or new antenna port indication)". In addition, DMRS ports and CDM groups without data allocation are referred to as "DMRS allocation".

[0194] The terminal can determine the number of antenna ports used when PDSCH is transmitted from a table indicating a DMRS port. The antenna port indication method based on rel-15 can be based on an index of 4 to 6 bits in length, indicated by the antenna port field of the DCI in the case of DCI format 1_1, and the antenna port can be determined thereby. The terminal can identify information about the number of DMRS ports and indexes, the number of front-loaded symbols, and the number of CDM groups used for PDSCH based on the indicator (index) sent by the base station. In addition, based on the information of the Transmit Configuration Indicator (TCI) field in DCI1_1, the terminal can determine the switching of the dynamic beamforming direction. When tci-PresentDCI is configured to be "enabled" in a higher layer, the terminal can identify the TCI field of 3 bits of information and determine the activated TCI state in the DL BWP or scheduled component carrier and the direction of the beam associated with the DL-RS. At the same time, when tci-PresentDCI is "disabled", the terminal can assume that the beam direction of the beamforming has not been switched.

[0195] In various embodiments, a scenario is considered in which a PDSCH transmitted from two (or more) different transmission points via a single PDCCH is allocated. The rel-15 terminal receives a PDSCH stream including a single layer or multiple layers, which is QCLed based on the TCI information and antenna port information in a single PDCCH. At the same time, the rel-16 terminal can receive data sent from multiple TRPs or multiple base stations in the form of C-JT / NC-JT. In order to support C-JT / NC-JT, the rel-16 terminal needs to perform basic higher-layer configuration. Specifically, for higher-layer configuration, the terminal needs to receive and configure parameters, setting values, etc. related to C-JT / NC-JT.

[0196] [Example 1]

[0197] In the present disclosure, for base stations and terminals supporting C-JT / NC-JT, a separate DMRS port table for C-JT / NC-JT signaling transmission or reception is proposed. The proposed DMRS port table can be distinguished as a separate table from the DMRS port table indicated by the antenna port field based on DCI format 1_1. The base station and the terminal can pre-configure information on whether NC-JT is supported in the RRC configuration as a method of distinguishing the table from the DMRS port table proposed in rel-15. That is, through the RRC configuration, a field such as "C-JT / NC-JT transmission = enable / disable" can be configured, and based on this field, it can be identified whether C-JT / NC-JT is supported.

[0198] When it is configured as "C-JT / NC-JT transmission = enabled" through higher layer signaling, the field to be used by the terminal can be indicated by using the existing antenna port field in DCI format 1_1. Alternatively, at least one of the detailed DMRS port number, the number of DMRS CDM groups without data, the number of (maximum) front loading symbols, and the DMRS type can be indicated for NC-JT by using a separate field in addition to the antenna port field in the separate DCI format 1_1.

[0199] [Table 12-1] to [Table 12-4] propose DMRS ports so that the DMRS ports transmitted from the same TRP will transmit to the same CDM group with reference to the CDM group described in [Table 11] above. In [Table 12-1] to [Table 12-4], the left and right reference semicolons (;) indicate different TPR transmissions and different CDM group mappings, but the semicolons may be omitted depending on the embodiment. In addition, the order of the values ​​of the reference semicolons (;) included in the table may be changed. In addition, the DMRS ports shown in the table take into account the case where a maximum of two DMRS ports are supported, namely the first TRP and the second TRP. In addition, the same basic concepts of DMRS ports, types, number of front-loaded symbols, etc. described in [Table 7] to [Table 10] may be applied to [Table 12-1] to [Table 12-4].

[0200] As shown in [Table 12-1], the DMRS port table of C-JT / NC-JT can be distinguished from the ports not supported in rel-15, and different types of ports can be supported.

[0201] For example, when the base station indicates entry (or value) 0 to the terminal, the terminal can determine that the first TRP and the second TRP transmit DMRS respectively through DMRS port 0 and DMRS port 2. In addition, the terminal that has identified that the number of ports for each TRP is 1 can determine that single-layer transmission is performed from each of the first TRP and the second TRP.

[0202] When the base station indicates entry 1 to the terminal, the terminal can determine that the first TRP and the second TRP transmit DMRS through DMRS port 1 and DMRS port 3, respectively. In addition, the terminal, which has recognized that the number of ports for each TRP is 1, can determine that single-layer transmission is performed from each of the first TRP and the second TRP. Entry 1 has a different number of ports from entry 0, but is functionally similar to entry 0. Therefore, entry 1 can be considered as a copy of entry 0 and omitted from the table.

[0203] When the base station indicates entry 2 to the terminal, the terminal can determine that the first TRP sends DMRS through DMRS ports 0 and 1, and the second TRP sends DMR through DMRS port 2. In addition, the terminal that has identified that the number of ports of the first TRP is 2 and the number of ports of the second TRP is 1 can determine to perform 2-layer transmission from the first TRP and 1-layer transmission from the second TRP.

[0204] When the base station indicates entry 3 to the terminal, the terminal can determine that the first TRP sends DMRS through DMRS port 0, and another second TRP sends DMRS through DMRS ports 2 and 3. In addition, the terminal that has identified that the number of ports of the first TRP is 1 and the number of ports of the second TRP is 2 can determine to perform single-layer transmission from the first TRP and 2-layer transmission from another second TRP.

[0205] The operations of the base station and the terminal of Items 4 and 5 can be easily understood from the above Items 2 and 3. Items 4 and 5 have different numbers of ports from Items 2 and 3, but are similar in function to Items 2 and 3, and thus may be omitted from the table.

[0206] When the base station indicates entry 6 to the terminal, the terminal can determine that the first TRP transmits DMRS through DMRS ports 0 and 1, and another second TRP transmits DMRS through DMRS ports 2 and 3. In addition, the terminal that has recognized that the number of ports per TRP is 2 can determine that 2-layer transmission is performed from each of the first TRP and another second TRP.

[0207] [Table 12-1] shows an embodiment in various cases by entry type, where a base station and a terminal communicate with each other, and all or part of the seven entries can be applied to an actual system. In addition, another table including at least one of the entries included in [Table 12-1] can be used. In addition, [Table 12-1] shows a case where a base station sends one codeword to a terminal, but can also be similarly applied to a case where two or more codewords are sent.

[0208] [Table 12-2] shows a case with the same DMRS type 1 as [Table 12-1] and a different maximum length (maximum length = 2) from [Table 12-1]. Referring to [Table 7] and [Table 8], the DMRS port configuration of C-JT / NC-JT can be mapped in the same form of maxLength = 1 for DMRS ports 0 to 3.

[0209] [Table 12-3] shows a DMRS port table of C-JT / NC-JT of DMRS type 2 which is different from DMRS type 1 described in [Table 12-1]. [Table 12-3] supports up to 12 DMRS ports and is a sufficient structure for MU-MIMO type.

[0210] For example, when the base station indicates entry 1 to the terminal, the terminal can determine that the first TRP and the second TRP send DMRS through DMRS port 0 and DMRS port 2, respectively. In addition, the terminal that has identified that the number of ports of each TRP is 1 can determine that single-layer transmission is performed from each of the first TRP and the second TRP. The entries in [Table 12-3] show the case where the number of DMRS CDM groups is 2 and the case where the number of DMRS CDM groups is 3, and do not exclude the case where the number of DMRS CDM groups is 2 and the case where the number of DMRS CDM groups is 3 indicated in the segmented entries. The embodiment is shown in terms of entry type, and all or part of the 14 entries can be applied to an actual system. For example, the table can be configured by only some of the entries 0, 2, 3, 6, 7, 9, 10 and 13. In addition, in the embodiment, the order of the entries is merely an embodiment and is not intended to limit the present disclosure. In addition, [Table 12-3] shows the case where the base station sends one codeword to the terminal, but it can also be similarly applied to the case where two or more codewords are sent.

[0211] [Table 12-4] shows a case with the same DMRS type 2 as [Table 12-3] and a different maximum length (maximum length = 2) from [Table 12-3]. Referring to [Table 7] and [Table 8], when DMRS ports are configured for C-JT / NC-JT, a total of two to four DMRS ports are allocated, and at least one DMRS port is allocated to each CDM group. Depending on the number of previous loading symbols, when the number of current loading symbols is 1, allocation is performed between DMRS ports 0-3 (this is omitted due to duplication of [Table 12-3]), and when the number of current loading symbols is 2, allocation is performed between DMRS ports 0-7. When a total of two DMRS ports are used, the frequency domain orthogonal cover code (OCC) of each CDM group needs to be the same.

[0212] At the same time, the time domain OCC of each CDM group can be the same or different. For example, DMRS ports 0 and 2 using the same time domain OCC in each of the CDM groups {0 and 1} can be used, and DMRS ports 0 and 6 using different time domain OCCs in each of the CDM groups {0 and 1} can also be used. When a total of three DMRS ports are used, the time domain OCC applied to each of the CDM groups {0 and 1} can be the same or different. The embodiment is shown in terms of entry type, and all or part of the 28 entries can be applied to an actual system.

[0213] For example, the table may be configured by only some of the entries 0, 2, 3, 6, 7, 9, 10, and 13 or only the entries 0, 2, 3, 6, 7, 9, 10, 13, 14, 16, 17, 20, 23, 24, and 27. In addition, in the embodiment, the order of the entries is merely an embodiment and is not intended to limit the present disclosure. In addition, [Table 12-4] shows the case where the base station sends one codeword to the terminal, but it can also be similarly applied to the case where two or more codewords are sent.

[0214] [Table 12-1] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=1, maxLength=1

[0215]

[0216] [Table 12-2] DMRS indication table for antenna port (1000+DMRS port), DMRS-Type=1, maximum length=2

[0217]

[0218] [Table 12-3] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=2, maxLength=1

[0219]

[0220]

[0221] [Table 12-4] DMRS indication table for antenna port (1000+DMRS port), DMRS-Type=2, maximum length=2

[0222]

[0223]

[0224] [Example 2]

[0225] [Table 13-1] proposes a method for using the code points of the reserved bits in the conventional rel-15 as a method for the base station to indicate the DMRS port to the terminal of C-JT / NC-JT. As shown in [Table 7], the rel-15 DMRS port table uses fields from 0 to 11, and does not use 12-15 as reserved bits. According to the present disclosure, the DMRS port can be indicated for collaborative transmission, wherein, as shown in [Table 13-1], transmission is performed from two TRPs by using four code points from 12 to 15 in the DMRS port table. When the same reserved bits are used, the base station and the terminal do not need to allocate separate fields, thereby efficiently using DCI resources.

[0226] For example, when the base station indicates entry 12 to the terminal, the terminal can determine that the first TRP and the second TRP transmit DMRS respectively through DMRS port 0 and DMRS port 2. In addition, the terminal that has identified that the number of ports for each TRP is 1 can determine that single-layer transmission is performed from each of the first TRP and the second TRP.

[0227] In another example, when the base station indicates entry 13 to the terminal, the terminal can determine that the first TRP transmits DMRS through DMRS ports 0 and 1, and the second TRP transmits DMR through DMRS port 2. In addition, the terminal that has identified that the number of ports of the first TRP is 2 and the number of ports of the second TRP is 1 can determine to perform 2-layer transmission from the first TRP and 1-layer transmission from the second TRP.

[0228] In another example, when the base station indicates entry 14 to the terminal, the terminal can determine that the first TRP transmits DMRS through DMRS port 0, and another second TRP transmits DMRS through DMRS ports 2 and 3. In addition, the terminal that has identified that the number of ports of the first TRP is 1 and the number of ports of the second TRP is 2 can determine to perform single-layer transmission from the first TRP and 2-layer transmission from another second TRP.

[0229] In another example, when the base station indicates entry 15 to the terminal, the terminal can determine that the first TRP transmits DMRS through DMRS ports 0 and 1, and another second TRP transmits DMRS through DMRS ports 2 and 3. In addition, the terminal that has recognized that the number of ports per TRP is 2 can determine that 2 layers of transmission are performed from each of the first TRP and another second TRP.

[0230] Here, a terminal configured as "C-JT / NC-JT transmission = enabled" in a higher layer can identify the remaining code points of the existing antenna port field in DCI format 1_1, and can use a dynamic method to determine whether C-JT / NC-JT is supported. That is, when the antenna port field of DCI format 1_1 is 12 to 15, the terminal can identify from the DCI the number of TRPs for scheduled PDSCH transmissions, the number of layers to be transmitted, the number of DMRS CDM groups without data, and the number of front-loaded symbols. The embodiment is shown in terms of entry type, and all or part of the 4 entries can be applied to an actual system. In the embodiment, the order of the entries is merely an embodiment and is not intended to limit the present disclosure.

[0231] For example, [Table 13-2] to [Table 13-4] correspond to an embodiment, in which some DMRS ports generated from [Table 12-2] to [Table 12-4] respectively are added to [Table 8] to [Table 10] defined by the rel-15 standard, and repeated DMRS ports are omitted to reduce the bit size. The omission method is only one embodiment, and the complete table can be configured by additionally using all or part of the DMRS ports indicated in [Table 12-1] to [Table 12-4]. In addition, the base station can perform scheduling of joint transmission for the rel-16NC-JT terminal, as shown in [Table 12-1] to [Table 13-4], and can also perform scheduling of single-port transmission to the same DMRS port for the rel-15 terminal, so that downlink MU-MIMO operation is performed.

[0232] In another example, since some of the entries in [Table 13-1] to [Table 13-4] have the same DMRS port index, the duplicate index can be omitted. That is, entries 12, 13, and 15 of NC-JT in [Table 13-1] have the same port index as entries 11, 9, and 10, respectively, and can be omitted. In addition, entries 31, 32, and 34 of NC-JT in [Table 13-2] have the same port index as entries 11, 9, and 10, respectively, and can be omitted. In addition, entries 24, 25, 27, 29, and 31 of NC-JT in [Table 13-3] have the same port index as entries 23, 9, 10, 29, and 22, respectively, and can be omitted. In addition, entries 58, 59, 61, 63, and 65 of NC-JT in [Table 13-4] have the same port index as entries 23, 9, 10, 20, and 22, respectively, and can be omitted. The repeated indexes may be omitted based on one of the assumptions that at least different CDM groups are not sent to the same port of NC-JT, the assumption that the terminal can distinguish the DMRS ports of NC-JT by indicating whether NC-JT is supported in the TCI field, and the assumption that the DMRS ports can be distinguished based on MAC CE message reception and DCI reception.

[0233] [Table 13-1] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=1, maxLength=1

[0234]

[0235] [Table 13-2] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=1, maxLength=2

[0236]

[0237]

[0238]

[0239] [Table 13-3] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=2, maxLength=1

[0240]

[0241]

[0242] [Table 13-4] DMRS indication table for antenna port (1000+DMRS port), dmrs-Type=2, maxLength=2

[0243]

[0244]

[0245]

[0246] The terminal can support data sent from multiple TRPs or multiple base stations in the form of C-JT / NC-JT. Terminals supporting C-JT / NC-JT can receive C-JT / NC-JT related parameters, setting values, etc. through higher-layer configuration, and can set the RRC parameters of the terminal based on this. For higher-layer configuration, the terminal can use the UE capability parameter tci-StatePDSCH. Here, the UE capability parameter tci-StatePDSCH defines the TCI states used for PDSCH transmission, where the number of TCI states can be configured to 4, 8, 16, 32, 64 and 128 in FR1, and can be configured to 64 and 128 in FR2, and among the configured number, a maximum of eight states that can be indicated by the 3-bit TCI field of DCI through the MAC CE message can be configured. The maximum value of 128 means the value indicated by the maxNumberConfiguredTCIstatesPerCC in the tci-StatePDSCH parameter included in the UE capability signaling. The serial configuration operation from higher layer configuration to MAC CE configuration can be applied to the beamforming indication or beamforming switching command of at least one PDSCH in one TRP.

[0247] Various embodiments describe how a terminal can activate or deactivate a TCI state through different MAC CE signaling such as rel-15 and rel-16. In particular, when a PDSCH (such as DCI format 1_1) is allocated for a specific terminal, the TCI field can be used to dynamically support a beamforming direction indication or a beamforming direction switching command.

[0248] The beamforming direction indication or beamforming direction switching command means the operation applied when a terminal that has recognized the TCI status field information of DCI format 1_1 receives PDSCH through the downlink after a predetermined time, and the direction means the beamforming configuration direction corresponding to the DL RS associated with the QCLed base station / TRP.

[0249] First, the base station and the terminal may determine to use each of the rel-15MAC CE for the rel-15DCI format and the rel-16MAC CE for the rel-16DCI format. According to the method for distinguishing the rel-15MAC CE structure and the rel-16MAC CE structure, other methods are proposed.

[0250] The rel-16MAC CE may be configured to have a form of partially extending the rel-15MAC CE message. This embodiment may propose that all TCI states activated by the rel-15MAC CE are included in the TCI states activated by the rel-16MAC CE.

[0251] For example, Fig.10 As shown, the base station can determine the number of all TCI states of TCI state 10-00 configured by rel-15RRC as M, including TCI#0, TCI#1, TCI#2... and TCI#M-1, and can select a subset 10-20 of TCI states selected by rel-15MACCE, TCI#0', TCI#1', TCI#2'... and TCI#K-1. At the same time, base stations and terminals supporting rel-16 can separately configure the TC states configured by RRC supporting rel-16, or can use the TCI states configured by RRC in rel-15 without change. In this case, the TCI states configured by RRC supporting rel-16 may include all or part of the TCI states configured by RRC in rel-15. When M=128, the number of TCI states of rel-16 can be equal to or greater than 128. When the base station or terminal expands the number of TCI states supported in rel-15 in proportion to the number of base stations / TRPs operating for C-JT / NC-JT in rel-16, a maximum of 256 TCI states can be configured when operating in two TRPs. Here, the rel-16MAC CE may include all or part of the TCI states supported by the rel-15MAC CE to the RRC TCI states configured for rel-16. Specifically, when the rel-16MAC CE includes all TCI states supported in the rel-15MAC CE, and the number of TCI states is expanded in proportion to the number of base stations / TRPs operating for C-JT / NC-JT in rel-16, a maximum of 2K TCI states can be configured when operating in two TRPs.

[0252] [Table 14] shows the details of the tci-StatePDSCH parameters described in the above embodiments. Specifically, for C-JT / NC-JT, the FR2 mandatory value of the parameter maxNumberConfiguredTCIstatesPerCC can be modified from 64 to 128 or 256, or 64, 128 or 256 can be added.

[0253] [Table 14]

[0254]

[0255]

[0256] For example, a base station or terminal supporting rel-15 and rel-16 can configure a maximum value for each of rel-15 and rel-16 for the TCI state through MAC CE, and can configure the number of TCI states to be equal to or less than the configured maximum value. As a method for configuring the number of TCI states to be equal to or less than the maximum value, various embodiments may be proposed below.

[0257] The number of TCI states activated by the MAC CE messages of rel-15 and rel-16 may be configured by the UE capability value reported by the terminal. According to another example, the number of TCI states activated by the MAC CE messages of rel-15 and rel-16 may be determined by a value pre-configured by the base station. According to another example, the number of TCI states activated by the MAC CE messages of rel-15 and rel-16 may be determined as a value pre-configured by the base station and the terminal.

[0258] For example, Fig.10 As shown, the base station and the terminal can determine the number of all TCI states 10-00 of the TCI state configured by the rel-15RRC as M, including TCI#0, TCI#1, TCI#2... and TCI#M-1, and can select a subset 10-20 of the TCI state selected by the rel-15MAC CE, and can arrange the subset as TCI#0', TCI#1', TCI#2'... and TCI#K-1. When TCI#0 is selected from M TCI states, TCI#0 can be arranged in TCI#0'. Here, for example, the maximum value of the K value of the base station and terminal supporting rel-15 can be configured to 8, and the maximum value of the K value of the base station and terminal supporting rel-16 can also be configured to 8. When the maximum value is configured to 8, the base station can indicate to the terminal to select a beam for PDSCH through a DCI-based beam selection operation in a CORESET. The selection of the beam can be determined by identifying the TCI field information 10-40 of the DCI from a maximum of eight beams. Fig.10 The TCI field #1 shown may be selected to have a value of 0 to 7. For example, when the TCI field of the DCI is indicated by 000, it may be determined that TCI #0' (TCI #1 = TCI #0') is indicated from TCI #0', TCI #1', TCI #2', TCI #3', TCI #4', TCI #5', TCI #6', and TCI #7'. In the above embodiment, it is described that each maximum value is configured as 8 (K = 8), but the maximum value may be configured as a value less than 8. In the above embodiment, it is described that the maximum value of the rel-15 MAC CE is the same as the maximum value of the rel-16 MAC CE, but different maximum values ​​may be configured.

[0259] In another example, when the number of TCI states expands in proportion to the number of base stations / TRPs operating for C-JT / NC-JT, the maximum value of the K value for base stations and terminals supporting rel-16 can be configured to 16 when operating in two TRPs. When the maximum value is configured to 16, the base station can indicate to the terminal through a DCI-based beam selection operation in one CORESET to select one or more beams for PDSCH. When K is 16, the #I selected and indicated by the base station can be a value from 0 to 15. In the above embodiment, it is described that each maximum value is configured to 16 (K=16), but the maximum value can be configured to a value less than 16.

[0260] [Table 15] shows a high-level signaling structure of TCI state and quasi-co-location (QCL) information. Referring to [Table 15], one TCI state includes at most two QCL types (qcl-type 1 and qcl-type 2), and one QCL type is connected to QCL information configured as one of type A, type B, type C, and type D. In this case, according to the QCL type, the type of large-scale parameter value that the target RS can refer to from the reference RS is as follows:

[0261] "QCL-Type A": {Doppler shift, Doppler spread, average delay, delay spread}

[0262] "QCL-Type B": {Doppler shift, Doppler spread}

[0263] "QCL-Type C": {Doppler shift, average delay}

[0264] "QCL-Type D": {Spatial Rx parameters} (i.e., receive beam related information).

[0265] exist Fig.15 In the embodiment, the QCL-information connected to the qcl-type 1 can be configured as one of QCL-type A (QCL-TypeA), QCL-type B (QCL-TypeB) and QCL-type C (QCL-TypeC). When the qcl-type 2 is configured, the QCL-information connected thereto is configured as QCL-type D (QCL-TypeD).

[0266] [Table 15]

[0267]

[0268] [Table 16] shows the attributes of the UE capability reporting parameters "PDSCH beam switching (or timeDurationForQCL (duration of QCL), UE capa 2-2)" and "maximum number of downlink RS resources for QCL type-D in active TCI state and active spatial relationship information (or UE capa 2-62)". Referring to [Table 16], the terminal can report to the base station the duration required for the receive beam to switch from a minimum of 7 symbols to a maximum of 28 symbols through timeDurationForQCL with reference to a subcarrier spacing (SCS) of 60kHz, or can report to the base station the duration required for the receive beam to switch from a minimum of 14 symbols to a maximum of 28 symbols through timeDurationForQCL with reference to a subcarrier spacing (SCS) of 120kHz. 60kHz and 120kHz SCS can be configured only in FR2, and according to [Table 16], timeDurationForQCL can also be used only in FR2. In addition, the terminal can notify the base station of the maximum number of downlink reference signals that can be used as reference RSs for QCL type D in the activated TCI state through "UE capa 2-62". For example, when the value of "UE capa 2-62" is 1, this means that the reference RS for QCL type D in the activated TCI state is one, and it can be interpreted that QCL type D, i.e., dynamic switching of receiving beams, may not be performed. At the same time, when "UE capa 2-62" has a value equal to or greater than 2, this means that the reference RS for QCL type D in the activated TCI state is two or more, and it can be interpreted that QCL type D, i.e., dynamic switching of receiving beams, may be performed.

[0269] [Table 16]

[0270]

[0271]

[0272] The base station based on rel-15 can allocate data considering the scheduling timing offset (t_so) from the time point when the PDCCH reception in the CORESET is completed to the time point when the PDSCH scheduled by the PDCCH is transmitted. The scheduling timing offset (t_so) means the time from the last symbol (next symbol) of the PDCCH used to allocate the PDSCH to ... Figure 8The duration of the symbol before the symbol at which the PDSCH that sends data in the corresponding time slot indicated by k0 shown. The scheduling timing offset (t_so) can determine the starting symbol of the PDSCH based on the starting point and length indicator (SLIV) index configured in the startSymbolAndLength (0 to 127) of the PDSCH-TimeDomainResourceAllocation (time domain resource allocation) configured in a higher layer. The application of beamforming may vary depending on the UE capability, and during the RRC configuration with the base station, the capability is transmitted to the base station as the timeDurationForQCL value. In the present disclosure, timeDurationForQCL may be referred to as the duration of the terminal applying QCL or the QCL application time interval.

[0273] Basically, the terminal can perform the following operations according to the value of the scheduling timing offset (t_so) and the value of timeDurationForQCL based on the UE capability to be configured in a higher layer.

[0274] When TCI-PresentinDCI (TCI present in DCI) is not configured as "enabled" in higher layer configuration, the terminal can identify that the scheduling offset / scheduling timing offset between PDCCH and PDSCH has a value equal to or greater than the timeDurationForQCL reported as the UE capability report, regardless of the DCI format.

[0275] When TCI-PresentinDCI is configured as "enabled" in a higher layer configuration and the terminal receives DCI format 1_1 from the base station, the terminal can assume that the TCI field is present in the corresponding DCI and can identify whether the scheduling timing offset between PDCCH and PDSCH has a value equal to or greater than the timeDurationForQCL reported as the UE capability report.

[0276] When the scheduling offset / scheduling timing offset between PDCCH and PDSCH has a value less than timeDurationForQCL, the terminal may determine the DMRS port of the received PDSCH based on the QCL parameters used in the CORESET associated with the monitored search space having the lowest CORESET ID in the latest slot.

[0277] In addition, for example, when the scheduling offset / scheduling timing offset between the PDCCH and the PDSCH has a value equal to or greater than timeDurationForQCL, the terminal applies the same QCL assumption as that of the CORESET for PDCCH transmission of the corresponding PDSCH DMRS port.

[0278] In another example, when the scheduling offset / scheduling timing offset between PDCCH and PDSCH has a value equal to or greater than timeDurationForQCL, the terminal applies the QCL assumption indicated by the TCI field in the corresponding PDCCH (DCI) for the corresponding PDSCH DMRS port. At the same time, in the TCI state configured by the terminal "for all BWPs", no TCI state is included in QCL type D, and the terminal can obtain the QCL assumption according to the TCI state that is always indicated, regardless of the interval between the DCI and the PDSCH allocated by the DCI.

[0279] Fig.11 shows the structure of a PDCCH sent by a base station according to at least one configured CORESET and search space, Fig.12 FIG13A shows the structure of the PDCCH sent by the base station according to at least one configured CORESET and search space, and FIG13B shows the structure of the PDCCH sent by the base station according to at least one configured CORESET and search space.

[0280] Fig.11 The base station is shown in Figure 8 In the embodiment of sending the first PDCCH in one CORESET (eg, the first CORESET or PDCCH#1), Fig.12 The base station is shown in Figure 8 FIG. 13A shows an embodiment in which a base station transmits a first PDCCH in a CORESET (eg, a first CORESET or PDCCH#1) as shown in FIG. Figure 8 FIG. 13B shows an embodiment in which a base station transmits a first PDCCH in a CORESET (eg, a first CORESET or PDCCH#1) as shown in FIG. Figure 8 An embodiment of sending the first PDCCH in one CORESET (e.g., the first CORESET or PDCCH#1) is shown. Specifically, the first PDCCH sent from TRP-A can perform scheduling of one or more PUCCH resources and two or more PDSCHs. DMRS ports of different CDM groups can be applied to each of the PDSCHs sent by the base station, and the DMRS transmission symbols sent with each of the PDSCHs can be located on the same symbol.

[0281] As long as the MAC CE is not updated, the base station applies the same beam direction to the PDCCH beam direction in a specific CORESET (TCI state) sent by the base station to a specific terminal. Fig.11 , Fig.12 13A and 13B, the Nth PDCCH (PDCCH#N) transmitted by the base station / TRP A corresponds to the PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID in the latest time slot. That is, unless a PDCCH beam switching update message is received, for the first PDCCH reception, the terminal applies the same QCL parameters used when receiving the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID in the latest time slot. It is described that the Nth PDCCH is transmitted from the previous time slot of the first PDCCH according to an embodiment describing transmission from different search spaces in the same CORESET, but the embodiment is not limited to transmission from another search space in the same time slot.

[0282] exist Fig.11 , Fig.12 13A and 13B, the first PDCCH and the second PDCCH may indicate that the first PDSCH and the second PDSCH are allocated for NC-JT, wherein the beamforming direction of the PDSCH may be switched depending on the beamforming information configured in a higher layer and the TCI information, antenna port information, or RNTI information of the DCI in the first PDCCH or the second PDCCH. The terminal may identify the beamforming direction switched by the base station based on the received beamforming information and DCI information.

[0283] For example, in Fig.11 In the example, for NC-JT, the beamforming direction of the first PDCCH may be different from the beamforming directions of the first PDSCH and the second PDSCH. In another example, for NC-JT, the beamforming direction of the first PDCCH may be the same as the beamforming direction of the first PDSCH and the second PDSCH. In another example, considering the spatial beamforming gain, the base station may configure the beamforming directions of the first PDSCH and the second PDSCH to be different from each other.

[0284] Fig.11 Operations of a base station and a terminal according to a relationship between timeDurationForQCL and a scheduling timing offset including the number and duration of symbols between the last symbol of a first PDCCH and the start symbol of a PDSCH are proposed.

[0285] The present disclosure defines the scheduling timing offset as the number of symbols between the last symbol of the PDCCH and the starting symbol of the PDSCH corresponding to the PDCCH, but the embodiments of the present disclosure are not limited thereto, and the scheduling timing offset may be differently defined as a symbol unit or a time slot unit having a predetermined value.

[0286] [Example 1-1]

[0287] For example, the base station may not support NC-JT-based transmission, in which the base station performs scheduling for a terminal by using a single PDCCH, in which tci-PresentinDCI is not configured to be "enabled" for the terminal. That is, the base station may allocate one PDSCH in one PDCCH for a terminal in which tci-PresentinDCI is not configured to be "enabled". When the base station allocates two or more PDSCHs to a specific terminal by performing scheduling using a single PDCCH, NC-JT-based transmission can be performed only when tci-PresentinDCI is configured to be "enabled" for the terminal. However, when multi-PDCCH scheduling is used, NC-JT-based transmission can be performed, and a description related thereto will be added in the following Example 5-1.

[0288] In another example, the base station may indicate NC-JT-based transmission, where the base station performs scheduling for the terminal by using a single PDCCH based on antenna port information in a single PDCCH, where tci-PresentinDCI is not configured as "enabled" for the terminal. Specifically, the base station may indicate information related to DMRS mapped to different CDM groups in the antenna port information to the terminal, so as to notify information related to multiple PDSCHs to be transmitted by the base station.

[0289] [Example 1-2]

[0290] The base station can support NC-JT-based transmission by performing scheduling for the terminal using DCI format 1_1 in a single PDCCH, where tci-PresentinDCI is configured as "enabled" for the terminal. In addition, in NC-JT-based transmission, the base station can perform data transmission to the terminal taking into account the scheduling timing offset (t_so) between a single PDCCH and multiple PDSCHs.

[0291] Fig.11 11-00 in FIG. 11 shows a case where the value of t_so scheduled by the base station is 14 or more. When the calculated value of t_so is 14 or more, the base station may perform determination and operation by using at least one of the methods proposed below.

[0292] For example, the base station may send the first PDCCH (DCI format 1_1) and the first PDSCH11-20 and the second PDSCH11-25 allocated by the first PDCCH11-10 for NC-JT-based transmission to a specific terminal in which the tci-PresentinDCI is configured as "enabled". In this case, the base station may send the first PDSCH11-20 and the second PDSCH11-25 based on the scheduling algorithm of the base station, without considering the timeDurationForQCL of the terminal. For example, the base station may indicate the beamforming direction of the transmitted PDSCH by using the antenna port information and TCI information in the DCI of the first PDCCH11-10. Here, the capabilities of the terminal are not considered during scheduling.

[0293] In another example, when the base station determines that the terminal can receive at least one PDSCH based on the terminal's timeDurationForQCL information and the TCI state-related information of the indicated first PDSCH and second PDSCH, for the NC-JT-based transmission of a specific terminal, the base station can send the first PDCCH and the first PDSCH and the second PDSCH allocated by the first PDCCH to the terminal.

[0294] In another example, when the base station determines that the terminal can receive two PDSCHs based on the terminal's timeDurationForQCL information and the TCI state-related information of the indicated first PDSCH and second PDSCH, for the NC-JT-based transmission of a specific terminal, the base station can send the first PDCCH and the first PDSCH and the second PDSCH allocated by the first PDCCH to the terminal.

[0295] [Example 2-1]

[0296] For example, when tci-PresentinDCI is not configured as "enabled", the terminal may not expect NC-JT-based transmission. That is, when tci-PresentinDCI is not configured as "enabled" or DCI format 1_0 is received, the terminal may assume that only one PDSCH corresponding to one PDCCH is transmitted. For example, the terminal may determine that the beamforming direction of the first PDCCH and the beamforming direction of the PDSCH indicated by the first PDCCH are the same.

[0297] In another example, when TCI-PresentinDCI is not configured as "enabled", the terminal can determine whether NC-JT is supported based on the antenna port information in the DCI. That is, the antenna port information may include information about whether the base station sends a single PDSCH or multiple PDSCHs. For example, the terminal can determine that the beamforming direction of the first PDCCH and at least one of the beamforming directions of the first PDSCH and the second PDSCH indicated by the first PDCCH are the same. Alternatively, the terminal can determine that the TCI state, that is, the beamforming direction of the first PDCCH and the beamforming direction of the first PDSCH and the second PDSCH indicated by the first PDCCH are configured as default.

[0298] [Example 2-2]

[0299] When receiving a message from a base station on DCI format 1_1 of the tci-PresentinDCI and the first PDCCH configured as "enabled", the terminal can calculate the scheduling timing offset (t_so) and compare the calculated scheduling timing offset (t_so) with the UE capability parameter timeDurationForQCL reported to the base station (e.g., S14).

[0300] Fig.11 11-00 in FIG. 1 shows a case where the value of t_so calculated by the terminal is 14 or more. When the value of t_so is 14 or more, the terminal may perform determination and operation by using at least one of the methods proposed below.

[0301] For example, the terminal may assume that there is a TCI field in the corresponding DCI, and may apply each of the QCL parameters (sets) of the TCI state indicating the beamforming direction of at least one PDSCH indicated by the code point of the TCI.

[0302] In another example, when the information indicated by the code point of TCI includes a TCI state, the terminal can assume that the TCI state of one of the two PDSCHs is the same as the TCI of the PDCCH. The terminal can apply QCL parameters for the first PDSCH and the second PDSCH based on the information of the configured TCI field, and can receive data.

[0303] Fig.11 11-50 in FIG. 11-50 show a case where t_so between PDCCH and PDSCH transmitted by the base station has a value less than 14. When t_so has a value less than 14, the base station may perform determination and operation by using at least one of the methods proposed below.

[0304] [Example 3-1]

[0305] In Example 3-1, when TCI-PresentinDCI is not configured as "enabled" by the base station, the base station may operate using the same method as Example 1-1.

[0306] [Example 3-2]

[0307] In Embodiment 3-2, operations are described in which the TCI-PresentinDCI configured by the base station as “enabled” and the DCI format 1_1 of the PDCCH are transmitted.

[0308] For example, for NC-JT-based transmission of a specific terminal, the base station may send the first PDCCH and the first PDSCH and the second PDSCH allocated by the first PDCCH based on the scheduling algorithm of the base station and without considering the timeDurationForQCL of the terminal. For example, the base station may indicate the beamforming direction of the PDSCH by using the antenna port information and TCI information in the DCI sent through the first PDCCH. Here, the capabilities of the terminal are not considered during scheduling. In another example, regarding the transmission of the first PDCCH and the transmission of the first PDSCH and the second PDSCH allocated by the first PDCCH, for NC-JT-based transmission of a specific terminal, when the base station determines that the terminal may not have received at least one PDSCH based on the DurationForQCL information of the terminal and the TCI state-related information of the indicated first PDSCH and the second PDSCH, the base station may only send a receivable PDSCH (e.g., PDSCH#1) to the terminal. In another example, regarding the transmission of the first PDCCH and the transmission of the first PDSCH and the second PDSCH allocated by the first PDCCH, for the NC-JT-based transmission of a specific terminal, when the base station determines that the terminal may not have received at least one PDSCH based on the DurationForQCL information of the terminal and the TCI state-related information of the indicated first PDSCH and the second PDSCH, the base station may transmit at least one of the first PDSCH and the second PDSCH based on the TCI state that can be received by the terminal (for example, the TCI state for receiving PDCCH#1 or PDCCH#N) and considering the timeDurationForQCL of the terminal. In another example, regarding the transmission of the first PDCCH and the transmission of the first PDSCH and the second PDSCH allocated by the first PDCCH, for the NC-JT-based transmission of a specific terminal, when the base station determines that the terminal may not have received at least one PDSCH considering only the timeDurationForQCL of the terminal, the base station may not perform any PDSCH (for example, PDSCH#1 and PDSCH#2) transmission that should be performed by the PDCCH.

[0309] When receiving a message from a base station on DCI format 1_1 of the tci-PresentinDCI and the first PDCCH configured as "enabled", the terminal can calculate the scheduling timing offset (t_so) and compare the calculated scheduling timing offset (t_so) with the UE capability parameter timeDurationForQCL reported to the base station (e.g., S14).

[0310] Fig.11 11-50 in FIG. 11-50 show a case where t_so calculated by the terminal has a value less than 14. When t_so has a value less than 14, the terminal may perform determination and operation by using at least one of the methods proposed below.

[0311] [Example 4-1]

[0312] When the value of the scheduling timing offset (t_so) calculated by the terminal is smaller than the value of the UE capability parameter timeDurationForQCL (eg, S14) reported to the base station, the terminal may not expect NC-JT based transmission of the base station.

[0313] For example, when the timeDurationForQCL required to apply the QCL parameter associated with the TCI state and indicating the beamforming direction of the PDSCH cannot be satisfied, the terminal can skip all PDSCH reception operations indicated by the PDCCH. In another example, when the timeDurationForQCL required to apply the QCL parameter associated with the TCI state and indicating the beamforming direction of the PDSCH cannot be satisfied, the terminal can apply the same QCL parameter for receiving the first PDSCH or the second PDSCH, which is used to receive the Nth PDCCH in the CORESET associated with the monitored search space with the lowest CORESET ID in the latest time slot. Specifically, the terminal can apply the QCL parameter to the first PDSCH and the second PDSCH, and can perform decoding. Therefore, when the base station performs NC-JT applying different beamforming directions, it is expected that the terminal can successfully selectively receive only one of the two PDSCHs.

[0314] [Example 4-2]

[0315] When the value of the scheduling timing offset (t_so) calculated by the terminal is less than the value of the UE capability parameter timeDurationForQCL (eg, S14) reported to the base station, the terminal may expect a single transmission-based transmission of the base station.

[0316] For example, when the timeDurationForQCL required for applying the QCL parameter indicating the beamforming direction of the PDSCH associated with the TCI state cannot be met, the terminal can use the QCL parameter for receiving the Nth PDCCH in the CORESET associated with the monitored search space with the lowest CORESETID in the latest time slot. Specifically, the terminal can receive data from the PDSCH (e.g., the first PDSCH / second PDSCH) allocated in the lowest / highest resource RB in the first PDSCH and the second PDSCH, and use the above-mentioned QCL parameter. In another example, when the timeDurationForQCL required for applying the QCL parameter indicating the beamforming direction of the PDSCH associated with the TCI state cannot be met, the terminal can apply the QCL parameter to both the first PDSCH and the second PDSCH, which is used to receive the Nth PDCCH in the CORESET associated with the monitored search space with the lowest CORESET ID in the latest time slot. In addition, the DMRS port configuration for receiving the first PDSCH and the second PDSCH can be received based on the antenna port information in the DCI.

[0317] In the above embodiments, it is expected that a default QCL is configured for the terminals in NC-JT based on a single PDCCH in a CORESET.

[0318] In addition, it is expected that two or more default QCLs are configured for the terminal in NC-JT based on a single PDCCH in one CORESET. The configuration of two or more default QCLs means that the terminal can apply QCL parameters for two PDSCHs (e.g., the first PDSCH and the second PDSCH) based on information preconfigured by the base station. The QCL parameters to be applied can be implicitly or explicitly configured based on the DCI information (e.g., antenna port information and TCI information) indicated to the terminal and the MAC CE or RRC information.

[0319] For example, when two or more default QCLs are configured for each CORESET or each PDCCH configuration, the base station can configure the beamforming direction of each of the TRPs to be the same as the beamforming direction of the terminal side performing the receiving operation based on the two default QCLs. Alternatively, the TCI state of each of the TRPs can be configured based on the assumption that the TRP performs the same beamforming on the terminal side. Here, the terminal determines that the TCI state is the same based on the MAC CE or RRC information implicitly or explicitly configured by the base station, and can perform a receiving operation based on this. Taking into account the channel and position of the TRP, the TCI states may be the same or different from each other. That is, the terminal can perform receive beamforming in the same direction by applying the QCL parameters to two PDSCHs (e.g., the first PDSCH and the second PDSCH).

[0320] In another example, when two or more default QCLs are configured for each CORESET or each PDCCH configuration, the base station can configure the two or more default QCLs to be the same on the base station side. That is, the two default QCLs are explicitly configured, but can be configured to indicate the same beamforming direction. Here, the terminal can recognize the same configuration of the TCI states configured by the base station and perform the same beamforming. Alternatively, the terminal may assume that the TCI states of the default QCLs configured by the base station are the same as each other, and may perform a receiving operation based on one TCI state. That is, the terminal can apply the same QCL parameters configured for two PDSCHs (e.g., the first PDSCH and the second PDSCH), and may perform receive beamforming in the same direction.

[0321] Meanwhile, the base station may sequentially configure two or more default QCLs for each CORESET or each PDCCH configuration. Alternatively, in some cases, two or more default QCLs may not be fully configured, but only one default QCL may be configured.

[0322] For example, the base station may configure a default QCL for the first PDSCH, and may later configure or not configure a default QCL for the second PDSCH. When only the default QCL of the first PDSCH configured in one serving cell, PDCCH configuration or CORESET (group) in each TRP is configured at a time point when the default QCL of the second PDSCH is not configured, the terminal may determine that the default QCL of the second PDSCH is the same as that of the first PDSCH. Alternatively, the terminal may determine that the default QCL of the second PDSCH is unnecessary, and may determine that the default QCL of the second PDSCH fails to be scheduled within the scheduling timing offset. Alternatively, the terminal may determine that the transmission of the second PDSCH is not performed. In other words, at a time point when the base station does not configure two or more default QCLs, the terminal may assume that two or more PDSCHs are not transmitted in a time slot in multiple TRPs based on a single DCI, and may determine that two or more PDSCHs are transmitted in a time slot in multiple TRPs after two or more default QCLs are configured.

[0323] exist Fig.12 , an embodiment is described in which a first PDCCH is transmitted in one CORESET (eg, CORESET#0 or PDCCH#1) and a second PDCCH is additionally transmitted in another CORESET (eg, CORESET#1 or PDCCH#2).

[0324] Specifically, the first PDCCH sent from TRP-A can schedule one or more PUCCH resources (first PDCCH) and one or more PDSCHs (first PDSCH), and the second PDCCH sent from TRP-B can schedule one or more PUCCH resources (second PUCCH) and one or more PDSCHs (second PDSCH). DMRS ports of different CDM groups can be applied to each of the PDSCHs sent by the base station, and the DMRS transmission symbols sent with each of the PDSCHs can be located on the same symbol. It is assumed that the PDSCH is sent in the same symbol, but the present disclosure is not intended to limit transmission only from the same symbol.

[0325] In addition, multiple CORESETs can be divided and configured for multi-DCI-based NC-JT of a base station. Alternatively, multiple CORESETs can be configured in a set format (such as a CORESET group) and can be indicated based on higher layer or L1 / L2 signaling of a terminal supporting NC-JT.

[0326] For example, for NC-JT based on multiple DCIs, the base station can configure a CORESET group including one or more CORESETs for a specific terminal. Specifically, the base station can configure four CORESETs in a CORESET group for a specific terminal. Therefore, the terminal can monitor the configured CORESETs and receive two PDCCHs, and can receive the allocated PDSCH from the received PDCCH. Fig.12 As shown, the base station can configure a CORESET group (e.g., CORESET group #0) for a specific terminal, and among the maximum five CORESETs (e.g., CORESET #0 to CORESET #4) included in the CORESET group, the terminal can monitor CORESET #0 and CORESET #1 for NC-JT. Here, the CORESET to be monitored by the terminal in the CORESET group can be configured by the base station, can be determined according to the configuration of the terminal, or can be determined in a predetermined manner. This can be applied to other embodiments.

[0327] In another example, for NC-JT based on multiple DCI, the base station can configure two or more CORESET groups including one or more CORESETs for a specific terminal. For example, the base station can configure two CORESET groups for a specific terminal, and can configure or indicate the CORESET in one CORESET group or in each of the CORESET groups in the configured group. Therefore, the terminal can monitor the configured CORESET, and receive two PDCCHs, and can receive the PDSCH allocated by the received PDCCH. Fig.12 As shown, the base station can configure two CORESET groups (e.g., CORESET group #0 and CORESET group #1) for a specific terminal, and among the CORESETs in the CORESET group, the terminal can monitor CORESET #0 in CORESET group #0 and CORESET #1 in CORESET group #1 for NC-JT. Here, the CORESET to be monitored by the terminal in the CORESET group can be configured by the base station, can be determined according to the configuration of the terminal, or can be determined in a predetermined manner.

[0328] CORESET#0 may include a first PDCCH and an Nth PDCCH, and CORESET#1 may include a second PDCCH and an N+1th PDCCH. The CORESETs configured for each CORESET group may be different (e.g., CORESET group #0 includes CORESET#0 and #2, and CORESET group #1 includes CORESET#1, #3, and #5), and the sum of the number of CORESETs configured in all CORESET groups may be within the maximum number of CORESETs that can be configured for the terminal (i.e., reported as UE capabilities). In the above embodiment, the maximum number of CORESETs may be 5 or less.

[0329] As long as the MAC CE is not updated, the base station applies the same beam direction to the PDCCH beam direction (TCI state) in a specific CORESET sent by the base station to a specific terminal.

[0330] Fig.12 It is shown that the Nth PDCCH (PDCCH#N) / N+1th PDCCH (PDCCH#N+1) transmitted from TRP-A / TRP-B is each of the PDCCHs in each CORESET associated with the monitored search space with the lowest CORESET ID in the latest time slot. That is, when the terminal does not receive the PDCCH beam switching update message, the same QCL parameters used to receive the Nth PDCCH / N+1th PDCCH in the CORESET associated with the monitored search space with the lowest CORESET ID in the latest time slot can be applied to receiving the first PDCCH / second PDCCH.

[0331] An embodiment describing transmission from different search spaces in the same CORESET is described in which the Nth PDCCH (PDCCH#N) / N+1th PDCCH (PDCCH#N+1) is transmitted from the same time slot of the first PDCCH / second PDCCH, but the embodiment is not limited to transmission from another search space of the previous time slot.

[0332] The first PDCCH and the second PDCCH may respectively indicate that the first PDSCH and the second PDSCH are allocated for NC-JT, wherein the beamforming direction of the PDSCH may be switched depending on the beamforming information configured in a higher layer and the TCI information, antenna port information, or RNTI information of the DCI in the first PDCCH or the second PDCCH. The terminal may identify the beamforming direction switched by the base station based on the received beamforming information and DCI information.

[0333] For example, for NC-JT, the beamforming direction of the first PDCCH may be different from the beamforming direction of the first PDSCH, and for NC-JT, the beamforming direction of the second PDCCH may be different from the beamforming direction of the second PDSCH.

[0334] In another example, for NC-JT, the beamforming direction of the first PDCCH may be the same as the beamforming direction of the first PDSCH, and for NC-JT, the beamforming direction of the second PDCCH may be the same as the beamforming direction of the second PDSCH.

[0335] In another example, considering the spatial beamforming gain, the base station may configure the beam directions of the first PDSCH and the second PDSCH to be different from each other.

[0336] Fig.12 The operation of the base station and the terminal according to the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the first PDCCH received by the terminal and the starting symbol of the first PDSCH) and the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the second PDCCH received by the terminal and the starting symbol of the second PDSCH) is proposed, and Figure 13A proposes the operation of the base station and the terminal according to the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the first PDCCH received by the terminal and the starting symbol of the first PDSCH) and the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the second PDCCH received by the terminal and the starting symbol of the second PDSCH), and Figure 13B proposes the operation of the base station and the terminal according to the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the first PDCCH received by the terminal and the starting symbol of the first PDSCH) and the relationship between timeDurationForQCL and the scheduling timing offset (corresponding to the duration between the last symbol of the second PDCCH received by the terminal and the starting symbol of the second PDSCH).

[0337] [Example 5-1]

[0338] When tci-PresentinDCI is not configured by the base station as "enabled" for the terminal, for NC-JT based transmission, the base station can perform scheduling without considering the scheduling timing offset (t_so) and timeDurationForQCL reported as UE capacity report.

[0339] [Example 5-2]

[0340] For example, when tci-PresentinDCI is configured by the base station to be "enabled" for the terminal, for transmission based on NC-JT, the base station can perform scheduling without considering the scheduling timing offset (t_so) and the timeDurationForQCL reported as the UE capacity report. The base station can determine whether to switch the transmission beams of the first PDSCH and the second PDSCH based on NC-JT without considering the UE capacity. Therefore, the base station can send the PDSCH based on the TCI field information of the PDCCH used to allocate the first PDSCH and the second PDSCH. In another example, when tci-PresentinDCI is configured by the base station to be "enabled" for a specific terminal, for transmission based on NC-JT, the base station can perform scheduling taking into account the scheduling timing offset (t_so) and the timeDurationForQCL reported as the UE capacity report. The base station can determine the beam direction of the PDSCH based on whether to switch the transmission beams of the first PDSCH and the second PDSCH based on NC-JT.

[0341] For example, Fig.12 As shown, a situation is described: in CORESET group #0 and CORESET group #1 (for example, CORESET group #0 includes CORSET #0 and #2, and CORESET group #1 includes CORSET #1, #3 and #5), the base station configures CORESET #0 in CORSET group #0 and CORESET #1 in CORSET group #1 for the terminal of NC-JT, and beam switching of the first PDSCH and the second PDSCH in the PDSCH to be transmitted in association with the PDCCH in the CORESET occurs. Here, for a specific terminal, the base station can perform at least one of the following operations: compare timeDurationForQCL with a first scheduling timing offset corresponding to the duration between the first PDCCH and the first PDSCH (beam switching of the PDSCH occurs), or compare timeDurationForQCL with a second scheduling timing offset corresponding to the duration between the second PDCCH and the second PDSCH. Therefore, when the value of each of the first scheduling timing offset and the second scheduling timing offset where beam switching occurs is less than the value of timeDurationForQCL, the base station can operate as follows.

[0342] According to one embodiment, the same QCL parameters used to send the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID (e.g., CORESET #0 and CORESET #1) in the latest time slot of each CORESET group (e.g., CORESET group #0 and CORESET group #1) may be applied to send the first PDSCH, and the same QCL parameters used to send the N+1th PDCCH may be applied to send the second PDSCH.

[0343] Specifically, in Fig.12 In the example, when PDSCH#1 is scheduled from CORESET group #0, the QCL parameters for PDCCH#N of the monitored search space corresponding to the lowest CORESET ID in the latest slot in the corresponding CORESET group are used to transmit PDSCH#1. At the same time, when PDSCH#2 is scheduled from CORESET group #1, similar to the above description, the QCL parameters for PDCCH#N+1 are used to transmit PDSCH#2. That is, the base station can set two CORESET groups for NC-JT, and the CORESET groups can correspond to TRPs, respectively. The corresponding lowest CORESET-ID in the CORESET group can refer to the QCL assumption of each PDSCH.

[0344] According to another embodiment, the same QCL parameters used to transmit the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID (e.g., CORESET #0) in the latest time slot of the lowest CORESET group (e.g., CORESET group #0) may be applied to transmit each of the first PDSCH and the second PDSCH.

[0345] According to another embodiment, the same QCL parameters used to transmit the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID (e.g., CORESET #0) in the latest slot of the lowest CORESET group (e.g., CORESET group #0) may be applied to transmit the first PDSCH, and the transmission of the second PDSCH may be deleted or may not be performed. That is, according to the lowest CORESET ID, the PDSCH may be preferentially transmitted.

[0346] In another example, a situation is described where the base station may configure a CORESET for NC-JT in CORESET group #0 (eg, CORESET group #0 includes CORESET #0 and CORESET #1). Fig.12CORESET#0 and CORESET#1), and beam switching of the first PDSCH and the second PDSCH in the PDSCH to be sent in association with the PDCCH in the CORESET occurs. Here, for a specific terminal, the base station may perform the following operations: compare timeDurationForQCL with a first scheduling timing offset (where beam switching of PDSCH occurs) corresponding to the duration between the first PDCCH and the first PDSCH, and compare timeDurationForQCL with a second scheduling timing offset corresponding to the duration between the second PDCCH and the second PDSCH. Therefore, when the value of the first scheduling timing offset or the second scheduling timing offset where beam switching of PDSCH occurs is less than the value of timeDurationForQCL, the base station may operate as described in the various embodiments below.

[0347] According to one embodiment, the same QCL parameters used to send the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID (e.g., CORESET #0 and CORESET #1) in the latest time slot of each CORESET group (e.g., CORESET group #0 and CORESET group #1) may be applied to send the first PDSCH, and the same QCL parameters used to send the N+1th PDCCH may be applied to send the second PDSCH.

[0348] According to another embodiment, the base station may apply the same QCL parameter to the transmission of each of the first PDSCH and the second PDSCH where beam switching occurs, which parameter is used to transmit the Nth PDCCH in the CORESET associated with the monitored search space based on information about the lowest CORESET ID (e.g., CORESET #0) in the latest time slot in the CORESET group (e.g., CORESET group #0) where beam switching occurs.

[0349] According to another embodiment, the base station may apply a QCL parameter for transmitting the Nth PDCCH in a CORESET associated with a monitored search space based on information about the lowest CORESET ID (e.g., CORESET #0) in the latest slot in a CORESET group (e.g., CORESET group #0) in which beam switching occurs to transmitting the first PDSCH, and may delete or may not perform transmission of the second PDSCH. That is, according to the lowest CORESET ID, the PDSCH may be preferentially transmitted.

[0350] Furthermore, in the above described embodiments, there are CORESET groups (e.g., CORESET group #0 includes CORESET #0 and CORESET #2). However, in some cases, there may be only CORESETs without the concept or configuration of CORESET groups. For the latter case, the solution may be obvious through analysis of the above CORESET ID description, the difference being only in the CORESET group excluded from the above description.

[0351] The above embodiment describes the case with the lowest CORESET / CORESET group ID, but the description may be extended to the case with the highest CORESET / CORESET group ID and so on.

[0352] In another example, when beam switching occurs in at least one of the PDSCHs to be transmitted, for a specific terminal, the base station may perform at least one of the following operations: compare timeDurationForQCL with a first scheduling timing offset corresponding to a duration between a first PDCCH and a first PDSCH, or compare timeDurationForQCL with a second scheduling timing offset corresponding to a duration between a second PDCCH and a second PDSCH. When the values ​​of the first scheduling timing offset and the second scheduling timing offset are both less than the value of timeDurationForQCL and timeDurationForQCL has a specific value (e.g., S7), the base station may select one of the QCL parameters for transmitting the Nth PDCCH and the N+1th PDCCH, and generally apply the selected QCL parameter to the beam direction of the first PDSCH and the second PDSCH. Specifically, the selection scheme may include the following schemes: selecting the lowest / highest CORESET ID, selecting the PDCCH index allocated in the latest search space, or selecting the longest time interval between the PDSCH transmission of the ACK / NACK for the PDSCH and the PUCCH transmission. According to the implementation scheme, multiple PDSCHs may be transmitted from TRP-A or TRP-B.

[0353] When receiving a message from a base station on DCI format 1_1 of the tci-PresentinDCI and the first PDCCH configured as "enabled", the terminal can calculate the scheduling timing offset (t_so) and compare the calculated scheduling timing offset (t_so) with the UE capability parameter timeDurationForQCL reported to the base station (e.g., S14). Fig.12It shows a case where the calculated value of t_so1 and the calculated value of t_so2 are both less than 14. When the calculated value of t_so is less than 14, the terminal may perform determination and operation by using at least one method proposed below.

[0354] [Example 6-1]

[0355] In one example, when tci-PresentinDCI is configured as "enabled" by the base station and the terminal receives DCI format 1_1 of the first PDCCH or the second PDCCH, when both calculated values ​​of the scheduling timing offset (t_so) are less than the UE capacity parameter timeDurationForQCL reported to the base station (e.g., S14), the terminal may not expect the base station's NC-JT-based transmission. For example, when the timeDurationForQCL required to apply the QCL parameter associated with the TCI state indicating the beamforming direction of the PDSCH cannot be met, the terminal can skip all PDSCH reception operations indicated by the PDCCH.

[0356] In another example, when both timeDurationForQCL required for applying the QCL parameters related to the TCI state and indicating the beamforming direction of the first PDSCH and the second PDSCH cannot be satisfied, the terminal may operate according to the following embodiment 5-2. A plurality of CORESET groups may be configured for the terminal, and in an embodiment, it is assumed that the first PDSCH is allocated in association with the PDCCH in the CORESET in CORESET group #0, and the second PDSCH is allocated in association with the PDCCH in the CORESET in CORESET group #1.

[0357] According to one embodiment, the terminal may apply first QCL parameter related information to receiving the first PDSCH, or may apply second QCL parameter related information for receiving the N+1th PDCCH to receiving the second PDSCH, the first QCL parameter related information being used to receive the Nth PDCCH in the CORESET associated with the monitored search space having the lowest CORESET ID (e.g., CORESET#0 and CORESET#1) in the latest time slot of the CORESET group (e.g., CORESET group #0 and CORESET group #1). Specifically, the terminal may apply the QCL parameter related information to the first PDSCH and the second PDSCH, respectively, and may perform decoding.

[0358] According to another embodiment, the terminal may apply first QCL parameter-related information to receiving a first PDSCH and receiving a second PDSCH, wherein the first QCL parameter-related information is used to receive an Nth PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in a latest time slot of a CORESET group (e.g., CORESET group #0 and CORESET group #1) in which beam switching occurs.

[0359] According to another embodiment, the terminal may apply first QCL parameter related information for receiving the Nth PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in the latest time slot in the lowest CORESET group of the CORESET group (e.g., CORESET group #0 and CORESET group #1) where beam switching occurs to receiving the first PDSCH, and may delete or may not perform reception of the second PDSCH. That is, according to the lowest CORESET ID, the PDSCH may be preferentially received.

[0360] In another example, when both timeDurationForQCL required for applying the QCL parameters associated with the TCI state and indicating the beamforming direction of the first PDSCH and the second PDSCH cannot be satisfied, the terminal may operate according to the following embodiment 5-2. Multiple CORESET groups may be configured for the terminal, and in an embodiment, it is assumed that the first PDSCH and the second PDSCH are allocated in association with the PDCCH in CORESET group #0 (for example, CORESET group #0 includes CORESET #0 to CORESET #4).

[0361] According to one embodiment, the terminal may apply a QCL parameter for receiving the first PDSCH and / or may apply a QCL parameter for receiving the N+1th PDCCH to receiving the second PDSCH, the QCL parameter being used to receive the Nth PDCCH in the CORESET associated with the monitored search space based on information about the lowest CORESET ID (e.g., CORESET#0) and / or the second lowest CORESET ID (e.g., CORESET#1) in the latest time slot in the CORESET group (e.g., CORESET group #0) where beam switching occurs. Specifically, Fig.12In the embodiment, when PDSCH#1 is scheduled from CORESET group #0, the terminal receives PDSCH#1 using the QCL parameters for PDCCH#N of the monitored search space corresponding to the lowest CORESET ID in the latest slot in the corresponding CORESET group. At the same time, when PDSCH#2 is scheduled from CORESET group #1, similar to the above, the terminal receives PDSCH#2 using the QCL parameters for PDCCH#N+1.

[0362] According to another embodiment, the terminal may apply a QCL parameter to receive a first PDSCH and / or a second PDSCH in which beam switching occurs, the parameter being used to receive the Nth PDCCH in a CORESET associated with the monitored search space based on information about the lowest CORESET ID (e.g., CORESET #0) in the latest time slot in the CORESET group (e.g., CORESET group #0) in which beam switching occurs.

[0363] According to another embodiment, the base station may apply a QCL parameter for receiving the Nth PDCCH in a CORESET associated with a monitored search space based on information about the lowest CORESET ID (e.g., CORESET #0) in the latest slot in a CORESET group (e.g., CORESET group #0) in which beam switching occurs to receiving the first PDSCH, and may delete or may not perform reception of the second PDSCH. That is, according to the lowest CORESET ID, the PDSCH may be preferentially received.

[0364] The above embodiment describes the case with the lowest CORESET ID, but the description may be extended to the case with the highest CORESET ID and so on.

[0365] Furthermore, in the above described embodiments, there are CORESET groups (e.g., CORESET group #0 includes CORESET #0 and CORESET #2). However, in some cases, there may be only CORESETs without the concept or configuration of CORESET groups. For the latter case, the solution may be obvious through analysis of the above CORESET ID description, the difference being only in the CORESET group excluded from the above description.

[0366] In another example, the timeDurationForQCL required to apply the QCL parameters associated with the TCI state and indicating the beamforming direction of the first PDSCH and the second PDSCH cannot be met, and the terminal can select at least one of the first QCL parameter-related information and the second QCL parameter-related information for receiving the Nth PDCCH in each CORESET associated with the monitored search space with the lowest CORESET ID in the latest time slot, apply the selected QCL parameter-related information to both the first PDSCH and the second PDSCH, and perform decoding. Specifically, the selection scheme can be determined by selecting the lowest / highest CORESET ID among multiple CORESETs, selecting the PDCCH index allocated in the latest search space, or selecting the longest time interval between the PDSCH transmission of the ACK / NACK for the PDSCH and the PUCCH transmission. According to the implementation scheme, multiple PDSCHs can be sent from TRP-A or TRP-B.

[0367] [Example 6-2]

[0368] For example, when tci-PresentinDCI is not configured as "enabled" by the base station or the terminal receives DCI format 1_0, the terminal can receive multiple PDSCHs based on NC-JT without considering the scheduling timing offset (t_so) and timeDurationForQCL reported as the UE capability report. That is, when tci-PresentinDCI is not configured as "enabled" by the base station or the terminal receives DCI format 1_0, the terminal can assume that only one PDSCH is allocated in one PDCCH and send it. For example, the terminal can determine that the beamforming direction of the first PDCCH and the beamforming direction of the first PDSCH indicated by the first PDCCH are the same, and the beamforming direction of the second PDCCH and the beamforming direction of the second PDSCH indicated by the second PDCCH are the same.

[0369] In another example, when TCI-PresentinDCI is not configured as "enabled" by the base station, the terminal may determine that NC-JT-based PDSCH transmission is not supported.

[0370] 13-00 in FIG13A shows a case where one of t_so1 and t_so2 calculated by the terminal has a value less than 14. According to an embodiment, the t_so2 value among the plurality of t_so values ​​is less than 14, and the base station and the terminal may perform determination and operation by using at least one of the methods proposed below.

[0371] [Example 7-1]

[0372] As described in Example 5-1, when the base station does not configure tci-PresentinDCI as "enabled" for a specific terminal, the base station can perform scheduling based on NC-JT transmission without considering the scheduling timing offset (t_so) and timeDurationForQCL reported as the UE capability report.

[0373] [Example 7-2]

[0374] For example, as described in Example 5-2, when the base station configures tci-PresentinDCI as "enabled" for a specific terminal, the base station can perform scheduling based on NC-JT transmission without considering the scheduling timing offset (t_so) and timeDurationForQCL reported as the UE capability report.

[0375] In another example, when the base station configures tci-PresentinDCI as "enabled" for a specific terminal, the base station can perform scheduling for NC-JT-based transmission, taking into account the scheduling timing offset (t_so) and the timeDurationForQCL reported as the UE capability report. The base station can determine the beam direction of the PDSCH based on whether to switch the first PDSCH and the second PDSCH based on the NC-JT transmission beam.

[0376] For example, as shown in FIG. 13A, a case is described in which, in CORESET group #0 and CORESET group #1 (for example, CORESET group #0 includes CORESET #0 and #2, and CORESET group #1 includes CORESET #1, #3, and #5), the base station configures CORESET #0 included in CORESET group #0 and CORESET #1 included in CORESET group #1 for the terminal of NC-JT, and beam switching of the first PDSCH and the second PDSCH in the PDSCH to be transmitted in association with the PDCCH in the CORESET occurs. Here, the base station may perform at least one of the following operations: compare timeDurationForQCL with a first scheduling timing offset (t_so1) corresponding to a duration between the first PDCCH and the first PDSCH, or compare timeDurationForQCL with a second scheduling timing offset (t_so2) corresponding to a duration between the second PDCCH and the second PDSCH. When the value of one of the first scheduling timing offset and the second scheduling timing offset is less than the value of timeDurationForQCL, the base station may operate as follows. In an embodiment, it is assumed that the value of t_so2 is smaller than the value of timeDurationForQCL.

[0377] According to one embodiment, the base station may apply a QCL parameter for sending a second PDSCH, the parameter being used to send an N+1th PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #1) in a latest time slot based on a CORESET group (e.g., CORESET group #0 and CORESET group #1) and a CORESET ID in the group (e.g., CORESET #1) (where the offset value is less than the value of timeDurationForQCL).

[0378] Specifically, in FIG. 13A , when PDSCH#2 is scheduled from CORESET group#1, the QCL parameters for PDCCH#N+1 of the monitored search space corresponding to the lowest CORESET ID in the latest slot in the corresponding CORESET group are used to transmit PDSCH#2.

[0379] According to another embodiment, the base station may apply a QCL parameter for sending the second PDSCH, which is used to send the Nth PDCCH in the CORESET associated with the monitored search space with the lowest CORESET ID (e.g., CORESET #0) in the latest time slot of the lowest CORESET group (CORESET #0) in the CORESET groups (e.g., CORESET group #0 and CORESET group #1).

[0380] According to another embodiment, according to the beamforming direction indicated by the CORESET (e.g., CORESET #0) in the CORESET group (e.g., CORESET group #0) in which the offset value is equal to or greater than timeDurationForQCL, that is, according to the information of the TCI field indicated by the second PDCCH, the base station may apply the QCL parameters to the beamforming direction of the PDSCH (second PDSCH) scheduled in the CORESET (e.g., CORESET #1) in the CORESET group (e.g., CORESET group #1) in which the offset value is less than the value of timeDurationForQCL. Here, when the beam direction is not switched in the first PDCCH, the base station may apply the QCL parameters of the first PDCCH (or the first PDSCH) to the second PDSCH.

[0381] According to another embodiment, the base station may compare t_so1 with timeDurationForQCL or t_so2 with timeDurationForQCL regardless of each CORESET group, and when t_so1 or t_so2 has a value less than timeDurationForQCL, the base station may not send (may stop or skip sending) the PDSCH (second PDSCH) scheduled in a CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL to a specific terminal.

[0382] In another example, a situation is described where, for a specific terminal, the base station configures CORESETs (CORESET#0 and CORESET#1) in CORESET group #0 (for example, CORESET group #0 includes CORESET#0 and CORESET#1) for NC-JT, and beam switching of at least one of the PDSCHs to be sent in association with the PDCCH in the CORESET occurs. Here, the base station may perform at least one of the following operations: compare timeDurationForQCL with a first scheduling timing offset corresponding to a duration between a first PDSCH and a first PDCCH (beam switching of the PDSCH occurs), or compare timeDurationForQCL with a second scheduling time corresponding to a duration between a second PDSCH and a second PDCCH. When the first scheduling timing offset or the second scheduling timing offset where beam switching of the PDSCH occurs has a value less than timeDurationForQCL, the base station may operate as described in the various embodiments below.

[0383] According to one embodiment, the base station may apply a QCL parameter for sending a second PDSCH, the parameter being used to send an Nth PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in a latest time slot based on a CORESET ID of a CORESET group (e.g., CORESET group #0) in which the offset value is less than the value of timeDurationForQCL.

[0384] According to another embodiment, the base station may apply a QCL parameter for sending the second PDSCH, which is used to send the Nth PDCCH in the CORESET associated with the monitored search space with the lowest CORESET ID (e.g., CORESET #0) in the latest time slot of the lowest CORESET group (CORESET #0) in the CORESET group (e.g., CORESET group #0).

[0385] According to another embodiment, for NC-JT, according to the beamforming direction indicated by the CORESET (e.g., CORESET#0) in which the offset value is equal to or greater than timeDurationForQCL, that is, according to the information of the TCI field indicated by the second PDCCH, the base station may apply the QCL parameters to the beamforming direction of the PDSCH (second PDSCH) scheduled in the CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL. Here, when the beam direction is not switched in the first PDCCH, the QCL parameters of the first PDCCH (or the first PDSCH) may be applied to the second PDSCH.

[0386] According to another embodiment, for NC-JT, the base station may compare t_so1 with timeDurationForQCL or t_so2 with timeDurationForQCL regardless of each CORESET group, and when t_so1 or t_so2 has a value less than timeDurationForQCL, the base station may not send a PDSCH (second PDSCH) scheduled in a CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL to a specific terminal.

[0387] Furthermore, in the above described embodiments, there are CORESET groups (e.g., CORESET group #0 includes CORESET #0 and CORESET #2). However, in some cases, there may be only CORESETs without the concept or configuration of CORESET groups. For the latter case, the solution may be obvious through analysis of the above CORESET ID description, the difference being only in the CORESET group excluded from the above description.

[0388] The above embodiment describes the case with the lowest CORESET / CORESET group ID, but the description may be extended to the case with the highest CORESET / CORESET group ID and so on.

[0389] [Example 8-1]

[0390] In the case where tci-PresentinDCI is configured as "enabled" by the base station and the terminal receives DCI format 1_1 of the first PDCCH or the second PDCCH, when the value of the scheduling timing offset (t_so) calculated by the terminal is less than the UE capacity parameter timeDurationForQCL reported to the base station (e.g., S14), the terminal may not expect the base station's NC-JT-based transmission. For example, when t_so1 has a value of 14 or greater and t_so2 has a value less than 14, the terminal may determine not to perform NC-JT-based transmission in the base station. That is, when the timeDurationForQCL required to apply the QCL parameter related to the TCI state and indicating the beamforming direction of the second PDSCH cannot be met, the terminal can skip the reception operation of the second PDSCH indicated by the second PDCCH.

[0391] [Example 8-2]

[0392] In the case where tci-PresentinDCI is configured as "enabled" by the base station and the terminal receives DCI format 1_1 of the first PDCCH or the second PDCCH, when the value of the scheduling timing offset (t_so) calculated in one CORSET is less than the UE capacity parameter timeDurationForQCL reported to the base station (e.g., S14), the terminal may consider the NC-JT-based transmission of the base station according to Embodiment 7-2 as follows. Multiple CORESET groups may be configured for the terminal, and in an embodiment, it is assumed that the first PDSCH is allocated in association with the PDCCH in the CORESET in CORESET group #0, and the second PDSCH is allocated in association with the PDCCH in the CORESET in CORESET group #1.

[0393] According to one embodiment, when t_so1 has a value of 14 or more in a CORESET in CORESET group #0 and t_so2 has a value less than 14 in a CORESET in CORESET group #1, the terminal may determine to perform NC-JT-based transmission in the base station. That is, when timeDurationForQCL required to apply a QCL parameter indicating a beamforming direction of a second PDSCH associated with a TCI state cannot be satisfied, the terminal may apply (cover) a QCL parameter for receiving an N+1th PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #1) in a latest slot based on a CORESET ID and a CORESET group (e.g., CORESET group #1) in which t_so2 has a value less than timeDurationForQCL to reception of the second PDSCH.

[0394] According to various embodiments, when t_so1 in a CORESET in CORESET group #0 has a value of 14 or greater and t_so2 in a CORESET in CORESET group #1 has a value less than 14, the terminal may determine to perform NC-JT based transmission in the base station. That is, the base station may apply a QCL parameter for receiving an N-th PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in a latest slot of a lowest CORESET group (CORESET #0) in a CORESET group (e.g., CORESET group #0 and CORESET group #1) to receive a second PDSCH.

[0395] According to another embodiment, when t_so1 in a CORESET in CORESET group #0 has a value of 14 or greater and t_so2 in a CORESET in CORESET group #1 has a value less than 14, the terminal may determine to perform NC-JT-based transmission in the base station. That is, according to the beamforming direction indicated by a CORESET (e.g., CORESET #0) in a CORESET group (e.g., CORESET group #0) in which the offset value is equal to or greater than timeDurationForQCL, that is, according to information of the TCI field indicated by the second PDCCH, the terminal may apply the QCL parameter to the beamforming direction of the PDSCH (second PDSCH) scheduled in a CORESET (e.g., CORESET #1) in a CORESET group (e.g., CORESET group #1) in which the offset value is less than the value of timeDurationForQCL. Here, when the beam direction is not switched in the first PDCCH, the terminal may apply the QCL parameter of the first PDCCH (or the first PDSCH) to the second PDSCH.

[0396] According to another embodiment, the base station may compare t_so1 with timeDurationForQCL or t_so2 with timeDurationForQCL regardless of each CORESET group, and when t_so1 or t_so2 has a value less than timeDurationForQCL, the base station may not send a PDSCH (second PDSCH) scheduled in a CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL to a specific terminal.

[0397] In another example, when tci-PresentinDCI is configured as "enabled" by the base station and the terminal receives DCI format 1_1 of the first PDCCH or the second PDCCH, when the value of the scheduling timing offset (t_so) calculated in one CORSET is less than the UE capacity parameter timeDurationForQCL reported to the base station (e.g., S14), the terminal may consider the NC-JT-based transmission of the base station according to Embodiment 7-2 as follows. This situation is described: for the terminal, a CORESET (e.g., CORESET#0 and CORESET#1) in CORSET group #0 (e.g., CORESET group #0 includes CORESET#0 to CORESET#4) may be configured for NC-JT, and beam switching of at least one of the PDSCHs to be transmitted in association with the PDCCH in the CORESET occurs. However, the present disclosure is not limited to this, and the number of CORESETs configured for the terminal may change depending on the configuration of the base station.

[0398] According to one embodiment, the terminal may apply a QCL parameter for receiving a second PDSCH, the parameter being used to receive an Nth PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in a latest time slot based on a CORESET ID of a CORESET group (e.g., CORESET group #0) in which an offset value is less than a value of timeDurationForQCL.

[0399] According to another embodiment, the terminal may apply a QCL parameter for receiving the Nth PDCCH in a CORESET associated with a monitored search space having a lowest CORESET ID (e.g., CORESET #0) in a latest time slot of a lowest CORESET group (CORESET #0) in a CORESET group (e.g., CORESET group #0) to receive a second PDSCH.

[0400] According to another embodiment, for NC-JT, according to the beamforming direction indicated by the CORESET (e.g., CORESET#0) in which the offset value is equal to or greater than timeDurationForQCL, that is, according to the information of the TCI field indicated by the second PDCCH, the terminal may apply the QCL parameters to the beamforming direction of the PDSCH (second PDSCH) scheduled in the CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL. Here, when the beam direction is not switched in the first PDCCH, the QCL parameters of the first PDCCH (or the first PDSCH) may be applied to the second PDSCH.

[0401] According to another embodiment, for NC-JT, the base station may compare t_so1 with timeDurationForQCL or t_so2 with timeDurationForQCL regardless of each CORESET group, and when t_so1 or t_so2 has a value less than timeDurationForQCL, the base station may not send a PDSCH (second PDSCH) scheduled in a CORESET (e.g., CORESET#1) in which the offset value is less than the value of timeDurationForQCL to a specific terminal.

[0402] Furthermore, in the above described embodiments, there are CORESET groups (e.g., CORESET group #0 includes CORESET #0 and CORESET #2). However, in some cases, there may be only CORESETs without the concept or configuration of CORESET groups. For the latter case, the solution may be obvious through analysis of the above CORESET ID description, the difference being only in the CORESET group excluded from the above description.

[0403] The above embodiment describes the case with the lowest CORESET / CORESET group ID, but the description may be extended to the case with the highest CORESET / CORESET group ID and so on.

[0404] [Example 8-3]

[0405] For example, when tci-PresentinDCI is not configured as "enabled" by the base station or the terminal receives DCI format 1_0, the terminal can receive multiple PDSCHs based on NC-JT without considering the scheduling timing offset (t_so) and timeDurationForQCL reported as the UE capability report. That is, when DCI format 1_0 is received, the terminal can assume that only one PDSCH allocated by one PDCCH is sent by the base station. For example, the terminal can determine that the beamforming direction of the first PDCCH and the beamforming direction of the first PDSCH indicated by the first PDCCH are the same, and the beamforming direction of the second PDCCH and the beamforming direction of the second PDSCH indicated by the second PDCCH are the same.

[0406] In another example, when TCI-PresentinDCI is not configured as "enabled" by the base station, the terminal may determine that NC-JT-based PDSCH transmission is not supported.

[0407] 13-50 in FIG. 13B shows a case where the duration (t_so1) between the last symbol of the first PDCCH and the start symbol of the first PDSCH and the duration (t_so2) between the last symbol of the second PDCCH and the start symbol of the second PDSCH calculated by the terminal have a value of 14 or greater. In this case, the base station and the terminal can perform determination and operation by using at least one of the methods proposed below.

[0408] [Example 9-1]

[0409] For example, when the above conditions are met, the base station can configure tci-PresentinDCI to always be "enabled" during NC-JT. Alternatively, when tci-PresentinDCI is configured as "enabled", the base station can configure the scheduling timing so that the timing conditions are always met during NC-JT.

[0410] In the case where tci-PresentinDCI is configured as "enabled" by the base station and the terminal receives DCI format 1_1 of the first PDCCH or the second PDCCH, when the value of the scheduling timing offset (t_so) is equal to or greater than the UE capability parameter timeDurationForQCL reported to the base station (e.g., S14), the terminal can apply the QCL assumption indicated by the TCI field in the corresponding PDCCH (TCI) to the corresponding PDSCH DMRS port. For example, the terminal can apply the QCL parameters related to the TCI state to the first PDSCH and the second PDSCH based on the TCI field information of the DCI of each of the first PDCCH and the second PDCCH in order to switch the beamforming direction of the PDSCH. When the CORESET group is also configured, the above operation can be easily applied by inferring according to embodiments 8-1 to 8-3.

[0411] [Example 9-2]

[0412] For example, when the base station does not configure tci-PresentinDCI as "enabled" or configures DCI format 1_0 for the terminal, the base station may not perform scheduling for NC-JT. That is, when tci-PresentinDCI is not configured as "enabled" by the base station or the terminal receives DCI format 1_0, the terminal may assume that the base station only sends one PDSCH allocated by one PDCCH. For example, the terminal may determine that the beamforming direction of the first PDCCH and the beamforming direction of the first PDSCH indicated by the first PDCCH are the same, and the beamforming direction of the second PDCCH and the beamforming direction of the second PDSCH indicated by the second PDCCH are the same.

[0413] In the above embodiments, the terminal may expect to configure one or more default QCLs in NC-JT based on multiple PDCCHs in one CORESET.

[0414] Fig.14 A method for receiving, by a terminal, a PDSCH based on NC-JT and a default QCL assumption according to an embodiment is shown.

[0415] During the RRC configuration process through the base station, the terminal can receive configuration information including at least one of one or more base station beamforming related parameters (tci-PresentinDCI) or at least one of the configuration information of the control channel and the data channel (PDDCH-configuration, PDSCH-configuration) (14-00).

[0416] In addition, the terminal may send UE capability information (timeDurationForQCL) (14-00) to the base station. The terminal may send UE capability information when requested from the base station or at a predetermined time point (e.g., during RRC configuration by the base station). Therefore, when the base station has received the UE capability information, the process of receiving the UE capability information may be omitted. Alternatively, according to the configuration information, the UE capability receiving operation itself may be omitted.

[0417] Later, the terminal receives the first PDCCH or the second PDCCH in a specific CORESET based on the configuration information from the base station.

[0418] In addition, the terminal can identify at least one of the resource allocation information, TCI-related information and antenna port information of the first PDSCH or the second PDSCH (14-10) based on the first PDCCH or the second PDCCH.

[0419] Based on the identified information, the terminal can calculate the scheduling timing offset between the PDCCH and the PDSCH (at least one of the scheduling timing offset between the first PDCCH and the first PDSCH or the scheduling timing offset between the second PDCCH and the second PDSCH), and can determine (14-20) at least one of the reception operation (or reception operation method) or reception beamforming direction of the first PDSCH or the second PDSCH based on the calculation result. In this case, determining the reception operation method by the terminal may include determining whether to receive data through at least one of the first PDSCH or the second PDSCH, or when determining data reception, determining at least one data reception method.

[0420] Based on at least one of the identified information (14-0) and the determination result (14-20), the terminal may receive data through the first PDSCH and the second PDSCH corresponding to the first PDCCH and the second PDCCH, respectively (14-30).

[0421] In addition, the terminal can perform decoding on the received data.

[0422] [Table 17] shows a simple listing of the abstract syntax notation (ASN.1) of the serving cell. In the following, an embodiment is described based on the higher layer information elements and field information shown in [Table 17] to distinguish the configuration of multi-TRP and multi-TRP based on NC-JT.

[0423] In [Table 17], the serving cell can be mapped to the corresponding cell index by the serving cell index (ServingCellIndex). Here, the serving cell index can mean: the ID of the serving cell; when the corresponding serving cell is the P cell (PCell) of the primary cell group, the value of 0; in the case of the PS cell, the value of the servCellIndex of the Sp cell configuration (SpCellConfig) information element (IE) configured as the PS cell (PSCell) and the s cell index (sCellIndex) of the S cell configuration (SCellConfig) IE in the case of the PS cell.

[0424] In addition, physCellId (physical cell Id) refers to the physical cell identifier of the serving cell, and the corresponding ID can be the value configured for the ServingCellConfigCommon IE. The configuration of transmission resources such as BWP and the configuration related to the downlink transmission channel of the corresponding serving cell can be defined by IEs such as ARFCN, PDSCH-serving cell configuration (PDSCH-ServingCellConfig), BWP, PDCCH-configuration (PDCCH-Config) and PDSCH-configuration (PDSCH-Config). Similarly, the configuration related to the uplink transmission of the corresponding serving cell can be defined by IEs such as ARFCN, PUSCH-serving cell configuration (PUSCH-ServingCellConfig), BWP, PUCCH-configuration (PUCCH-Config) and PUSCH-configuration (PUSCH-Config). For multi-TRP transmission based on NC-JT, a pair or a group of TRPs can be configured based on the parameters or IEs in [Table 17].

[0425] For example, for multi-TRP transmission based on NC-JT, a pair or a group of TRPs can be configured or divided in units of ServingCell IE. In this case, when the TRP is divided with reference to each serving cell, a pair or a group of TRPs can be configured for NC-JT-based transmission. When any changes are required, the serving cells can be additionally combined and changed. That is, different serving cell objects can be mapped for each of the TRPs, so that multiple base stations are operated. In addition, a pair of serving cell sets can be configured, and separate higher-layer parameters can be configured from them. Here, for NC-JT, multiple TRPs can have the same SSB carrier or an SCS-specific carrier. In addition, multiple TRPs can include the same SCS, the same carrier BW, and the same point A (the common reference point of the resource block grid or the lowest subcarrier of the common RB 0).

[0426] In another example, for multi-TRP transmission based on NC-JT, a pair or a group of TRPs can be configured or divided in units of PDCCH configurations (PDCCH-configs). In this case, since multiple TRPs include the same service cell, the terminal can determine that the multiple TRPs are the same cell. When the base station configures a pair or a group of TRPs for NC-JT in units of PDDCH configurations (PDDCH-configs), the terminal can determine the configuration and change of the TRP through the configuration and change of the PDCCH configuration during the RRC configuration or reconfiguration process. That is, two or more multi-TRPs can be configured with multiple CORESETs and search spaces (SearchSpaces) through PDCCH configuration, and different scrambling IDs or different time / frequency resources can be additionally allocated. Here, up to five CORESETs can be used for each PDCCH configuration of URLLC, and the TRP can be configured with independent TCI states for PDCCH diversity performance.

[0427] In another example, for multi-TRP transmission based on NC-JT, under PDCCH configuration, a pair or a group of TRPs can be configured or divided in units of CORESET or CORESET group. In this case, since multiple TRPs include the same service cell, the terminal can determine that the multiple TRPs are the same cell. When the base station configures a pair or a group of TRPs in units of CORESET or CORESET group for NC-JT, the terminal can determine the configuration and change of TRP through the configuration and change of CORESET (index) or CORESET group (index) under PDCCH configuration during RRC configuration or reconfiguration. That is, for the transmission of two or more multi-TRPs, the CORESET indexes can be associated with each other, or the CORESET group index configured for each CORESET can be used so that the CORESETs of the TRPs are mapped to be associated with each other and operate.

[0428] Taking into account the capacity value of the terminal, the maximum number of CORESETs configured to the same TRP can be determined according to the capabilities of the terminal, and the base station can configure the maximum candidate value of the CORESET to be a minimum of three to a maximum of five (for example, URLLC scenario). In addition, the maximum number of CORESET groups (indexes) supported by the terminal can be configured to be equal to or less than the maximum number of CORESETs configured for the terminal. Terminals supporting NC-JT in rel-16 support up to two CORESET groups. The terminal can store the configured CORESET groups (indexes) in a memory according to the capacity value of the terminal, and can manage them based on this.

[0429] When a higher layer index is configured for a CORESET, in case of multi-DCI based operation, and when multiple dataScramblingIdentityPDSCH parameters are configured, each dataScramblingIdentityPDSCH is associated with a higher layer index for each CORESET and is applied to the PDSCH of the DCI that has been identified in the CORESET with the same higher layer index.

[0430] [Table 17]

[0431]

[0432]

[0433] Fig.15 is a block diagram showing a structure of a terminal in a wireless communication system according to an embodiment.

[0434] refer to Fig.15 , the terminal may include a terminal receiver 15-00, a terminal transmitter 15-10 and a terminal processor 15-05.

[0435] The terminal receiver 15-00 and the terminal transmitter 15-10 may be referred to as a "transceiver". According to the above-mentioned terminal communication method, the terminal receiver 15-00, the terminal transmitter 15-10 and the terminal processor 15-05 of the terminal may operate. However, the elements of the terminal are not limited to the above-mentioned examples. For example, the terminal may include more elements (e.g., memory, etc.) or may include fewer elements. In addition, the terminal receiver 15-00, the terminal transmitter 15-10 and the terminal processor 15-05 may be implemented in the form of a single chip.

[0436] Terminal receiver 15-00, terminal transmitter 15-10 (or transceiver) can send a signal to the base station or receive a signal from the base station. Here, the signal may include control information and data. For this reason, the transceiver may include an RF transmitter for up-converting the frequency of the signal to be sent and amplifying the signal, and an RF receiver for low-noise amplification of the received signal and down-converting the frequency of the received signal. However, it is only an embodiment of a transceiver, and the elements of the transceiver are not limited to RF transmitters and RF receivers.

[0437] In addition, the transceiver can receive a signal through a wireless channel, output the received signal to the terminal processor 15-05, and transmit a signal output from the terminal processor 15-05 through the wireless channel.

[0438] The memory (not shown) can store data or programs required for operating the terminal. In addition, the memory can store data or control information included in the signal obtained by the terminal. The memory can be configured as a storage medium or a combination of storage media, including ROM, RAM, hard disk, CD-ROM, DVD, etc.

[0439] The terminal processor 15-05 may control a series of processes so that the terminal operates according to the above-described embodiments. The terminal processor 15-05 may be implemented as a controller or one or more processors.

[0440] Fig.16 is a block diagram showing a structure of a base station in a wireless communication system according to an embodiment.

[0441] refer to Fig.16 , the base station may include a base station receiver 16-00, a base station transmitter 16-10 and a base station processor 16-05.

[0442] The base station receiver 16-00 and the base station transmitter 16-10 may be referred to as a "transceiver". According to the above-mentioned terminal communication method, the base station receiver 16-00, the base station transmitter 16-10 and the base station processor 16-05 of the base station may operate. However, the elements of the base station are not limited to the above-mentioned examples. For example, the base station may include more elements (e.g., memory, etc.) or may include fewer elements. In addition, the base station receiver 16-00, the base station transmitter 16-10 and the base station processor 16-05 may be implemented in the form of a single chip.

[0443] The base station receiver 16-00 and the base station transmitter 16-10 (or transceiver) can send signals to or receive signals from the terminal. Here, the signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting the frequency of the signal to be sent and amplifying the signal, and an RF receiver for low-noise amplification of the received signal and down-converting the frequency of the received signal. However, it is only an embodiment of the transceiver, and the elements of the transceiver are not limited to the RF transmitter and the RF receiver.

[0444] In addition, the transceiver can receive a signal through a wireless channel, output the received signal to the base station processor 16-05, and transmit a signal output from the base station processor 16-05 through the wireless channel.

[0445] The memory (not shown) may store data or programs required to operate the terminal. In addition, the memory may store data or control information included in the signal obtained by the base station. The memory may be configured as a storage medium or a combination of storage media, including ROM, RAM, hard disk, CD-ROM, DVD, etc.

[0446] The base station processor 16-05 may control a series of processes so that the terminal operates according to the above-described embodiments. The base station processor 16-05 may be implemented as a controller or one or more processors.

[0447] In the drawings describing the methods of the present disclosure, the order of description does not always correspond to the order of performing the steps of each method, and the sequential relationship between the steps may be changed or the steps may be performed in parallel.

[0448] Alternatively, in the drawings describing the method of the present disclosure, some elements may be omitted, and only some elements may be included therein without departing from the essential spirit and scope of the present disclosure.

[0449] Furthermore, in the method of the present disclosure, some or all of the contents of each embodiment may be combined without departing from the essential spirit and scope of the present disclosure.

[0450] Furthermore, although not disclosed herein, a method of using a separate table or information including at least one element included in the table proposed in the present disclosure is possible.

[0451] The embodiments of the present disclosure described and shown in the specification and the drawings are presented for the purpose of easily explaining the technical content of the present disclosure and helping to understand the present disclosure, and are not intended to limit the scope of the present disclosure. That is, on the basis of the technical spirit of the present disclosure, other modifications and changes may be made thereto, which will be apparent to those skilled in the art. In addition, if necessary, the above-mentioned corresponding embodiments may be used in combination. For example, embodiments 1 to 9 of the present disclosure may be partially combined to operate a base station and a terminal.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receiving configuration information for configuring a plurality of control resource sets CORESET; Based on the configuration information, identifying a first CORESET associated with a first CORESET group and a second CORESET associated with a second CORESET group, wherein an index of the first CORESET group and an index of the second CORESET group have different values ​​and the index of the first CORESET group is lower than an index of the second CORESET group; Receiving, on the first CORESET, a first physical downlink control channel PDCCH that schedules a first physical downlink shared channel PDSCH; Receiving, on the second CORESET, a second PDCCH scheduling a second PDSCH; determining a reception operation method for at least one of the first PDSCH or the second PDSCH based on (i) a comparison between a duration of the QCL and a first time offset between the first PDCCH and the first PDSCH, and (ii) a comparison between a duration of the QCL and a second time offset between the second PDCCH and the second PDSCH, and Based on the determination, receiving at least one of the first PDSCH or the second PDSCH; Wherein, in a case where (i) the first time offset between the first PDCCH and the first PDSCH and (ii) the second time offset between the second PDCCH and the second PDSCH are both smaller than the duration of the QCL: Determining the receiving operation method includes: determining to receive the first PDSCH corresponding to a lower CORESET group index and skipping receiving the second PDSCH, and The first QCL information for receiving the first PDSCH is determined by a QCL parameter in a latest time slot in which the terminal monitors one or more CORESETs associated with the first CORESET group, the QCL parameter being used for a PDCCH of a CORESET associated with a monitored search space and having a lowest CORESET ID among the one or more CORESETs included in the first CORESET group, and The duration of the QCL indicates the number of orthogonal frequency division multiplexing OFDM symbols required by the terminal, counted from the end of the last symbol received by the PDCCH to the beginning of the first symbol received by the PDSCH.

2. The method of claim 1, wherein: The configuration for each CORESET includes sending configuration indication TCI information and parameters, the TCI information provides the QCL relationship between the reference signal sent in each CORESET and the PDCCH demodulation reference signal DMRS, and the parameters indicate whether the TCI field exists in the downlink control information DCI format.

3. The method according to claim 2, in, The parameter indicates that the TCI field is present in the DCI format, Wherein, when the first time offset between the first PDCCH and the first PDSCH is equal to or greater than the duration of the QCL, the terminal determines that the QCL information indicated by the TCI field of the DCI format of the first PDCCH is applied to the DMRS port of the first PDSCH, and In which, when the second time offset between the second PDCCH and the second PDSCH is equal to or greater than the duration of the QCL, the terminal determines that the QCL information indicated by the TCI field of the DCI format of the second PDCCH is applied to the DMRS port of the second PDSCH.

4. The method according to claim 2, in, The parameter indicates that the TCI field is not present in the DCI format, In which, when the first time offset between the first PDCCH and the first PDSCH is equal to or greater than the duration of the QCL, and the second time offset between the second PDCCH and the second PDSCH is equal to or greater than the duration of the QCL, the first QCL information for receiving the first PDSCH is the same as any QCL assumption applied to receiving the first PDCCH, and the second QCL information for receiving the second PDSCH is the same as any QCL assumption applied to receiving the second PDCCH.

5. The method of claim 1, further comprising: Capability information including information about the duration of the QCL is sent.

6. A terminal, comprising: Transceiver; as well as A controller, the controller being configured to: Receiving configuration information for configuring a plurality of control resource sets CORESET; Based on the configuration information, identifying a first CORESET associated with a first CORESET group and a second CORESET associated with a second CORESET group, wherein an index of the first CORESET group and an index of the second CORESET group have different values ​​and the index of the first CORESET group is lower than an index of the second CORESET group; Receiving, on the first CORESET, a first physical downlink control channel PDCCH that schedules a first physical downlink shared channel PDSCH; Receiving, on the second CORESET, a second PDCCH scheduling a second PDSCH; determining a reception operation method for at least one of the first PDSCH or the second PDSCH based on (i) a comparison between a duration of the QCL and a first time offset between the first PDCCH and the first PDSCH, and (ii) a comparison between a duration of the QCL and a second time offset between the second PDCCH and the second PDSCH, and Based on the determination, receiving at least one of the first PDSCH or the second PDSCH; Wherein, in a case where (i) the first time offset between the first PDCCH and the first PDSCH and (ii) the second time offset between the second PDCCH and the second PDSCH are both smaller than the duration of the QCL: The controller is configured to: determine to receive the first PDSCH corresponding to a lower CORESET group index and skip receiving the second PDSCH, and The first QCL information for receiving the first PDSCH is determined by a QCL parameter in a latest time slot in which the terminal monitors one or more CORESETs associated with the first CORESET group, the QCL parameter being used for a PDCCH of a CORESET associated with a monitored search space and having a lowest CORESET ID among the one or more CORESETs included in the first CORESET group, and The duration of the QCL indicates the number of orthogonal frequency division multiplexing OFDM symbols required by the terminal, counted from the end of the last symbol received by the PDCCH to the beginning of the first symbol received by the PDSCH.

7. The terminal according to claim 6, wherein: The configuration for each CORESET includes sending configuration indication TCI information and parameters, the TCI information provides the QCL relationship between the reference signal sent in each CORESET and the PDCCH demodulation reference signal DMRS, and the parameters indicate whether the TCI field exists in the downlink control information DCI format.

8. The terminal according to claim 7, in, The parameter indicates that the TCI field is present in the DCI format, Wherein, when the first time offset between the first PDCCH and the first PDSCH is equal to or greater than the duration of the QCL, the terminal determines that the QCL information indicated by the TCI field of the DCI format of the first PDCCH is applied to the DMRS port of the first PDSCH, and In which, when the second time offset between the second PDCCH and the second PDSCH is equal to or greater than the duration of the QCL, the terminal determines that the QCL information indicated by the TCI field of the DCI format of the second PDCCH is applied to the DMRS port of the second PDSCH.

9. The terminal according to claim 7, in, The parameter indicates that the TCI field is not present in the DCI format, In which, when the first time offset between the first PDCCH and the first PDSCH is equal to or greater than the duration of the QCL, and the second time offset between the second PDCCH and the second PDSCH is equal to or greater than the duration of the QCL, the first QCL information for receiving the first PDSCH is the same as any QCL assumption applied to receiving the first PDCCH, and the second QCL information for receiving the second PDSCH is the same as any QCL assumption applied to receiving the second PDCCH.

10. The terminal according to claim 6, wherein the controller is configured to: Capability information including information about the duration of the QCL is sent.

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