Method and apparatus for transmitting uplink phase tracking reference signal in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. Specifically, the disclosure relates to a method performed by a terminal in a wireless communication system, the method being capable of receiving, from a base station, first RRC message including information related to the number of PTRS ports and a second RRC message including configuration information for supporting three transmission antennas. The method can: receive, from the base station, a DCI message including information related to the association of PTRS ports and DMRS ports; and transmit a PTRS to the base station through a DMRS port corresponding to a PTRS port determined on the basis of the number of PTRS ports and the information related to the association of the PTRS ports and the DMRS ports.

Description

Method and device for transmitting uplink phase tracking reference signals in a wireless communication system

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system (or, mobile communication system). Specifically, the present disclosure relates to a method for performing uplink transmission using a plurality of antennas (e.g., three antennas) in a wireless communication system, a method for configuring a reference signal for phase tracking when transmitting a reference signal for the operation, a method for transmitting the configured reference signal together with a scheduled uplink channel, and a device capable of performing the same.

[0002] 5G mobile communication technology defines a wide frequency band to enable fast transmission speeds and new services, and can be implemented not only in the sub-6GHz frequency band, such as 3.5 gigahertz (3.5GHz), but also in the ultra-high frequency band called millimeter wave (mmWave), such as 28GHz and 39GHz ('Above 6GHz'). In addition, for 6G mobile communication technology, which is called the system after 5G communication (Beyond 5G), implementation in the terahertz band (for example, the 3 terahertz (3THz) band at 95GHz) is being considered to achieve a transmission speed that is 50 times faster than 5G mobile communication technology and an ultra-low latency time that is reduced to one-tenth.

[0003] In the early stages of 5G mobile communication technology, the goal is to support services and meet performance requirements for enhanced Mobile Broadband (eMBB), Ultra Reliable & Low Latency Communications (URLLC), and massive Machine-Type Communications (mMTC). These include beamforming and massive MIMO to mitigate path loss of radio waves in ultra-high frequency bands and increase the transmission distance of radio waves, dynamic operation of numerology (multiple subcarrier interval operation, etc.) and slot formats for efficient use of ultra-high frequency resources, initial access technology to support multi-beam transmission and wideband, definition and operation of BWP (Bidth Part), new channel coding methods such as LDPC (Low Density Parity Check) codes for large-capacity data transmission and Polar Code for reliable transmission of control information, L2 pre-processing, and specific Standardization has been progressed for network slicing, which provides dedicated networks specialized for services.

[0004] Currently, discussions are underway to improve and enhance the initial 5G mobile communication technology in consideration of the services that 5G mobile communication technology was intended to support, and physical layer standardization is in progress for technologies such as V2X to assist in driving decisions of autonomous vehicles and increase user convenience based on the vehicle's own location and status information transmitted by the vehicle, NR-U (New Radio Unlicensed) for the purpose of system operation that complies with various regulatory requirements in unlicensed bands, NR terminal low power consumption technology (UE Power Saving), Non Terrestrial Network (NTN), which is direct terminal-satellite communication to secure coverage in areas where communication with terrestrial networks is impossible, and Positioning.

[0005] In addition, standardization of wireless interface architecture / protocols is in progress for technologies such as intelligent factories (Industrial Internet of Things, IIoT) to support new services through linkage and convergence with other industries, Integrated Access and Backhaul (IAB) that provides nodes for expanding network service areas by integrating wireless backhaul links and access links, Mobility Enhancement technology including Conditional Handover and Dual Active Protocol Stack (DAPS) handover, and 2-step random access (2-step RACH for NR) that simplifies random access procedures. Standardization is also in progress for system architecture / services such as 5G baseline architecture (e.g., Service-based Architecture, Service-based Interface) for grafting Network Functions Virtualization (NFV) and Software-Defined Network (SDN) technologies, and Mobile Edge Computing (MEC) that provides services based on the location of the terminal.

[0006] Once these 5G mobile communication systems are commercialized, an explosive increase in connected devices will be connected to the communication network, necessitating enhanced functionality and performance of 5G mobile communication systems and integrated operation of these connected devices. To this end, new research will be conducted on improving 5G performance and reducing complexity, supporting AI services, metaverse services, and drone communications by leveraging extended reality (XR), artificial intelligence (AI), and machine learning (ML) to efficiently support augmented reality (AR) and virtual reality (VR).

[0007] In addition, the development of these 5G mobile communication systems includes new waveforms to ensure coverage in the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), Array Antenna, and Large Scale Antenna, metamaterial-based lenses and antennas to improve the coverage of terahertz band signals, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), Reconfigurable Intelligent Surface (RIS) technology, as well as full duplex technology to improve the frequency efficiency and system network of 6G mobile communication technology, satellite, AI (Artificial Intelligence) from the design stage and AI-based communication technology that realizes system optimization by internalizing end-to-end AI support functions, and ultra-high-performance communication and computing resources to provide services with complexity that exceeds the limits of terminal computing capabilities. It can serve as a basis for the development of next-generation distributed computing technologies that can be realized by utilizing them.

[0008] Meanwhile, with the development of communication systems, research is being conducted on uplink transmission and reception processes using multiple panels, and in particular, there is an increasing demand for concretizing simultaneous uplink transmission using multiple panels.

[0009] Various embodiments of the present disclosure aim to provide devices and methods capable of effectively providing services in a mobile communication system. Various embodiments of the present disclosure aim to provide specific methods for configuring a phase tracking reference signal for simultaneous transmission of multiple uplink channels using multiple panels in a wireless communication system and transmitting the signal together with the uplink channel transmission.

[0010] According to various embodiments of the present disclosure, a device and method for effectively providing a service in a mobile communication system can be provided.

[0011] According to various embodiments of the present disclosure, a method for configuring a plurality of uplink channels with a phase tracking reference signal and simultaneously transmitting the same to a plurality of panels in a wireless communication system can be provided, and a device for performing the same can be provided.

[0012] According to one embodiment of the present disclosure, a method performed by a terminal in a wireless communication system is provided. The method may receive, from a base station, a first radio resource control (RRC) message including information regarding the number of PTRS (phase tracking reference signal) ports and a second RRC message including configuration information for supporting three transmission antennas. The method may receive, from the base station, a downlink control information (DCI) message including information regarding an association between PTRS ports and demodulation reference signal (DMRS) ports. The method may transmit a PTRS to the base station through a DMRS port corresponding to a PTRS port determined based on the number of PTRS ports and the information regarding the association between the PTRS ports and the DMRS ports.

[0013] According to one embodiment of the present disclosure, a terminal performing communication in a wireless communication system may include a transceiver and at least one processor connected to the transceiver. The at least one processor may transmit, to the terminal, a first RRC message including information regarding the number of PTRS ports and a second RRC message including configuration information for supporting three transmission antennas. The at least one processor may transmit, to the terminal, a DCI message including information regarding associations between PTRS ports and DMRS ports. The at least one processor may receive a PTRS from the terminal through a DMRS port corresponding to a PTRS port determined based on the number of PTRS ports and the information regarding associations between the PTRS ports and DMRS ports.

[0014] FIG. 1 is a diagram illustrating an example of a PUSCH (physical uplink shared channel) repetitive transmission type B in a wireless communication system according to one embodiment of the present disclosure.

[0015] FIG. 2 is a diagram illustrating a method for allocating comb offset and cyclic shift during SRS transmission according to an embodiment of the present disclosure.

[0016] FIG. 3 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0017] FIG. 4 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0018] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0019] In describing the embodiments, descriptions of technical details that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to ensure that the gist of the present disclosure is conveyed more clearly without obscuring it by omitting unnecessary explanations.

[0020] For the same reason, some components in the attached drawings are exaggerated, omitted, or schematically depicted. Furthermore, the dimensions of each component do not entirely reflect its actual size. Identical or corresponding components in each drawing are assigned the same reference numbers.

[0021] The advantages and features of the present disclosure, and methods for achieving them, will become clearer with reference to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present disclosure is complete and to fully inform those skilled in the art of the scope of the disclosure, and the present disclosure is defined only by the scope of the claims. Like reference numerals designate like elements throughout the specification. In addition, when describing the present disclosure, if a specific description of a related function or configuration is determined to unnecessarily obscure the gist of the present disclosure, the detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of the functions of the present disclosure, and these may vary depending on the intention or custom of the user or operator. Therefore, their definitions should be made based on the contents throughout the specification.

[0022] At this time, it will be understood that each block of the processing flowchart drawings and combinations of the flowchart drawings can be performed by computer program instructions. These computer program instructions can be installed in a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, so that the instructions executed by the processor of the computer or other programmable data processing equipment create a means for performing the functions described in the flowchart block(s). These computer program instructions can also be stored in a computer-available or computer-readable memory that can direct a computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-available or computer-readable memory can also produce a manufactured item that includes an instruction means for performing the functions described in the flowchart block(s). Since the computer program instructions may be installed on a computer or other programmable data processing device, a series of operational steps may be performed on the computer or other programmable data processing device to create a computer-executable process, and the instructions that cause the computer or other programmable data processing device to perform the steps for performing the functions described in the flowchart block(s) may also provide steps for performing the functions described in the flowchart block(s).

[0023] Additionally, each block may represent a module, segment, or portion of code that contains one or more executable instructions for performing a specific logical function(s). It should also be noted that in some alternative implementation examples, the functions described in the blocks may occur out of order. For example, two blocks depicted in succession may actually be executed substantially concurrently, or the blocks may sometimes be executed in reverse order, depending on their respective functions.

[0024] Here, the term '~ part' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and the '~ part' performs certain roles. However, the '~ part' is not limited to software or hardware. The '~ part' may be configured to be on an addressable storage medium or may be configured to play one or more processors. Therefore, as an example, the '~ part' includes components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and '~ parts' may be combined into a smaller number of components and '~ parts' or further separated into additional components and '~ parts'. Additionally, the components and '~parts' may be implemented to activate one or more CPUs within a device or secure multimedia card. In addition, in an embodiment, the '~parts' may include one or more processors.

[0025] Wireless communication systems are evolving from providing voice-oriented services in the early days to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards such as 3GPP's HSPA (High Speed ​​Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's HRPD (High Rate Packet Data), UMB (Ultra Mobile Broadband), and IEEE's 802.16e.

[0026] As a representative example of the above broadband wireless communication system, the LTE system adopts the OFDM (Orthogonal Frequency Division Multiplexing) method in the downlink (DL) and the SC-FDMA (Single Carrier Frequency Division Multiple Access) method in the uplink (UL). The uplink refers to a wireless link in which a user equipment (UE) or mobile station (MS) transmits data or control signals to a base station (eNode B or Base Station, BS), and the downlink refers to a wireless link in which a base station transmits data or control signals to a user equipment (UE). The above multiple access method can distinguish the data or control information of each user by allocating and operating the time-frequency resources for transmitting data or control information to each user so that they do not overlap, that is, so that orthogonality is achieved.

[0027] As the next-generation communications system after LTE, 5G must be able to freely reflect the diverse needs of users and service providers, and thus support services that simultaneously satisfy these requirements. Services being considered for 5G include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC).

[0028] eMBB aims to provide data transmission rates that are significantly higher than those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to support a peak data rate of 20 Gbps in the downlink and a peak data rate of 10 Gbps in the uplink from the perspective of a single base station. Furthermore, 5G communication systems must simultaneously provide the peak data rate and an increased user-perceived data rate for terminals. To meet these requirements, improvements in various transmission and reception technologies, including improved multi-input, multi-output (MIMO) transmission technology, are required. Furthermore, while LTE transmits signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the data transmission rates required by 5G communication systems by using a wider frequency bandwidth than 20 MHz in the 3-6 GHz or higher 6 GHz band.

[0029] At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide the IoT, mMTC requires supporting large-scale terminal connections within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. The IoT requires the ability to support a large number of terminals (e.g., 1,000,000 terminals / km^2) within a cell, as it provides communication capabilities through the attachment of various sensors and devices. Furthermore, due to the nature of the service, terminals supporting mMTC are likely to be located in shadow areas not covered by cells, such as basements, and thus may require wider coverage than other services provided by 5G communication systems. Terminals supporting mMTC must be inexpensive, and since frequent battery replacement is unlikely, they may require extremely long battery lifespans, such as 10 to 15 years.

[0030] Finally, URLLC refers to a cellular-based wireless communication service used for a specific purpose (mission-critical). Examples include remote control of robots or machinery, industrial automation, unmanned aerial vehicles (UAVs), remote health care, and emergency alerts. Therefore, URLLC communications must offer extremely low latency and high reliability. For example, services supporting URLLC must meet air interface latency requirements of less than 0.5 milliseconds and a packet error rate (PER) of 10-5 or lower. Therefore, for services supporting URLLC, 5G systems must provide a shorter Transmit Time Interval (TTI) than other services, and design considerations may require the allocation of extensive resources in the frequency band to ensure communication link reliability.

[0031] The three 5G services—eMBB, URLLC, and mMTC—can be multiplexed and transmitted within a single system. To meet the differing requirements of each service, different transmission and reception techniques and parameters can be used. Of course, 5G is not limited to the three services described above.

[0032] Hereinafter, the base station is an entity that performs resource allocation of the terminal, and may be at least one of a gNode B, an eNode B, a Node B, a BS (Base Station), a wireless access unit, a base station controller, or a node on a network. The terminal may include a UE (User Equipment), an MS (Mobile Station), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing a communication function. In the present disclosure, downlink (DL) refers to a wireless transmission path of a signal transmitted from a base station to a terminal, and uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station. In addition, although the LTE or LTE-A system may be described below as an example, the embodiments of the present disclosure may also be applied to other communication systems having a similar technical background or channel type. For example, the 5th generation mobile communication technology (5G, new radio, NR) developed after LTE-A may be included here, and the 5G below may also be a concept that includes existing LTE, LTE-A, and other similar services. In addition, the present disclosure may be applied to other communication systems with some modifications within a scope that does not significantly deviate from the scope of the present disclosure, as judged by a person having skilled technical knowledge.

[0033] Hereinafter, a / b can be understood as at least one of a or b.

[0034] [PDCCH: DCI related]

[0035] Next, we will specifically explain downlink control information (DCI) in 5G systems.

[0036] In a 5G system, scheduling information for uplink data (or physical uplink shared channel (PUSCH)) or downlink data (or physical downlink shared channel (PDSCH)) is transmitted from a base station to a terminal via DCI. The terminal can monitor a DCI format for fallback and a DCI format for non-fallback for the PUSCH or PDSCH. The fallback DCI format can be composed of fixed fields predefined between the base station and the terminal, and the non-fallback DCI format can include configurable fields.

[0037] DCI can be transmitted through the Physical Downlink Control Channel (PDCCH) after going through the channel coding and modulation process. A Cyclic Redundancy Check (CRC) is attached to the DCI message payload, and the CRC can be scrambled with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE. Different RNTIs can be used depending on the purpose of the DCI message, such as UE-specific data transmission, power control command, or random access response. That is, the RNTI is not transmitted explicitly, but is included in the CRC calculation process. When the UE receives a DCI message transmitted on the PDCCH, it verifies the CRC using the assigned RNTI. If the CRC verification result is correct, the UE can determine that the message was transmitted to the UE.

[0038] For example, a DCI scheduling a PDSCH for System Information (SI) may be scrambled with SI-RNTI. A DCI scheduling a PDSCH for a Random Access Response (RAR) message may be scrambled with RA-RNTI. A DCI scheduling a PDSCH for a Paging message may be scrambled with P-RNTI. A DCI notifying a Slot Format Indicator (SFI) may be scrambled with SFI-RNTI. A DCI notifying a Transmit Power Control (TPC) may be scrambled with TPC-RNTI. A DCI scheduling a UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

[0039] DCI format 0_0 can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_0 with the CRC scrambled with C-RNTI can include, for example, the following information.

[0040] [Table 1]

[0041]

[0042] DCI format 0_1 ​​can be used as a fallback DCI for scheduling PUSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 0_1 ​​with the CRC scrambled with C-RNTI can include, for example, the following information.

[0043] [Table 2]

[0044]

[0045]

[0046] DCI format 1_0 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_0 with the CRC scrambled with C-RNTI can include, for example, the following information.

[0047] [Table 3]

[0048]

[0049] DCI format 1_1 can be used as a fallback DCI for scheduling PDSCH, in which case the CRC can be scrambled with C-RNTI. DCI format 1_1 with the CRC scrambled with C-RNTI can include, for example, the following information.

[0050] [Table 4]

[0051]

[0052] [PUSCH: Transmission method related]

[0053] Next, we describe the scheduling method for PUSCH transmission. PUSCH transmission can be dynamically scheduled by the UL grant within the DCI or can operate by configured grant Type 1 or Type 2. Dynamic scheduling instructions for PUSCH transmission are possible in DCI format 0_0 or 0_1.

[0054] Configured grant Type 1 PUSCH transmission can be semi-statically configured by receiving configuredGrantConfig containing rrc-ConfiguredUplinkGrant of [Table 5] through higher-order signaling, without receiving UL grant in DCI. Configured grant Type 2 PUSCH transmission can be semi-persistently scheduled by UL grant in DCI after receiving configuredGrantConfig not containing rrc-ConfiguredUplinkGrant of [Table 5] through higher-order signaling. When PUSCH transmission operates by configured grant, parameters applied to PUSCH transmission are applied through configuredGrantConfig of higher-order signaling of [Table 5], except for dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and scaling of UCI-OnPUSCH provided by pusch-Config of [Table 6]. If the terminal has been provided with transformPrecoder in configuredGrantConfig, which is the upper signaling of [Table 5], the terminal applies tp-pi2BPSK in pusch-Config of [Table 5] to PUSCH transmission operated by the configured grant.

[0055] [Table 5]

[0056]

[0057]

[0058] Next, the PUSCH transmission method is described. The DMRS antenna port for PUSCH transmission is the same as the antenna port for SRS transmission. PUSCH transmission can follow a codebook-based or non-codebook-based transmission method, respectively, depending on whether the value of txConfig in the upper signaling pusch-Config in [Table 6] is 'codebook' or 'nonCodebook'.

[0059] As described above, PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, and can be semi-statically configured by configured grant. If the UE is instructed to schedule PUSCH transmission via DCI format 0_0, the UE performs beam configuration for PUSCH transmission using pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the minimum ID within the activated uplink BWP within the serving cell, and the PUSCH transmission is based on a single antenna port. The UE does not expect scheduling for PUSCH transmission via DCI format 0_0 within a BWP where a PUCCH resource including pucch-spatialRelationInfo is not configured. If the UE does not configure txConfig in pusch-Config of [Table 6], the UE does not expect to be scheduled with DCI format 0_1.

[0060] [Table 6]

[0061]

[0062]

[0063] Next, we describe codebook-based PUSCH transmission. Codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, or can operate semi-statically based on a configured grant. When codebook-based PUSCH is dynamically scheduled via DCI format 0_1 ​​or semi-statically configured via a configured grant, the UE determines a precoder for PUSCH transmission based on the SRS Resource Indicator (SRI), Transmission Precoding Matrix Indicator (TPMI), and transmission rank (the number of PUSCH transmission layers).

[0064] At this time, the SRI can be given through the SRS resource indicator field in the DCI or configured through the srs-ResourceIndicator higher-level signaling. The UE is configured with at least one SRS resource when transmitting a codebook-based PUSCH, and can be configured with up to two. When the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. In addition, the TPMI and transmission rank can be given through the precoding information and number of layers fields in the DCI or configured through the precodingAndNumberOfLayers higher-level signaling. The TPMI is used to indicate the precoder applied to the PUSCH transmission. If the UE is configured with one SRS resource, the TPMI is used to indicate the precoder to be applied to the configured one SRS resource. When a terminal is configured with multiple SRS resources, TPMI is used to indicate the precoder to be applied in the SRS resource indicated through SRI.

[0065] The precoder to be used for PUSCH transmission is selected from an uplink codebook having the same number of antenna ports as the nrofSRS-Ports value in the upper layer signaling, SRS-Config. In codebook-based PUSCH transmission, the UE determines the codebook subset based on the TPMI and codebookSubset in the upper layer signaling, pusch-Config. The codebookSubset in the upper layer signaling, pusch-Config, can be set to one of 'fullyAndPartialAndNonCoherent', 'partialAndNonCoherent', or 'nonCoherent' based on the UE capability reported by the UE to the base station. If the UE reported 'partialAndNonCoherent' as the UE capability, the UE does not expect the value of codebookSubset in the upper layer signaling to be set to 'fullyAndPartialAndNonCoherent'. Additionally, if the UE reports 'nonCoherent' as the UE capability, the UE does not expect the value of the upper signaling codebookSubset to be set to 'fullyAndPartialAndNonCoherent' or 'partialAndNonCoherent'. If nrofSRS-Ports in the upper signaling SRS-ResourceSet points to two SRS antenna ports, the UE does not expect the value of the upper signaling codebookSubset to be set to 'partialAndNonCoherent'.

[0066] The terminal can be configured with one SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', and one SRS resource in the SRS resource set can be indicated via SRI. If multiple SRS resources are configured in the SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'codebook', the terminal expects that the value of nrofSRS-Ports in the upper signaling SRS-Resource is set to the same value for all SRS resources.

[0067] The terminal transmits to the base station one or more SRS resources included in the SRS resource set in which the usage value is set to 'codebook' according to upper signaling, and the base station selects one of the SRS resources transmitted by the terminal and instructs the terminal to perform PUSCH transmission using transmission beam information of the corresponding SRS resource. At this time, in codebook-based PUSCH transmission, the SRI is used as information for selecting an index of one SRS resource and is included in the DCI. Additionally, the base station includes in the DCI information indicating the TPMI and rank to be used by the terminal for PUSCH transmission. The terminal performs PUSCH transmission by applying the indicated rank and the precoder indicated by the TPMI based on the transmission beam of the corresponding SRS resource using the SRS resource indicated by the SRI.

[0068] Next, we describe non-codebook-based PUSCH transmission. Non-codebook-based PUSCH transmission can be dynamically scheduled via DCI format 0_0 or 0_1, and can operate semi-statically based on a configured grant. If at least one SRS resource is configured within an SRS resource set in which the usage value in the upper signaling, SRS-ResourceSet, is set to 'nonCodebook', the UE can be scheduled for non-codebook-based PUSCH transmission via DCI format 0_1.

[0069] For an SRS resource set in which the usage value in the upper signaling SRS-ResourceSet is set to 'nonCodebook', the UE can be configured with one connected NZP CSI-RS resource (non-zero power CSI-RS). The UE can perform calculations for a precoder for SRS transmission by measuring the NZP CSI-RS resource connected to the SRS resource set. If the difference between the last received symbol of the aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of the aperiodic SRS transmission at the UE is less than 42 symbols, the UE does not expect information about the precoder for SRS transmission to be updated.

[0070] If the value of resourceType in the upper signaling SRS-ResourceSet is set to 'aperiodic', the connected NZP CSI-RS is indicated by the SRS request field in DCI format 0_1 ​​or 1_1. At this time, if the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, the presence of the connected NZP CSI-RS is indicated when the value of the SRS request field in DCI format 0_1 ​​or 1_1 is not '00'. At this time, the DCI must not indicate cross-carrier or cross BWP scheduling. In addition, if the value of the SRS request indicates the presence of an NZP CSI-RS, the NZP CSI-RS is located in the slot in which the PDCCH including the SRS request field is transmitted. At this time, the TCI states set for the scheduled subcarriers are not set to QCL-TypeD.

[0071] If a periodic or semi-persistent SRS resource set is configured, the associated NZP CSI-RS can be indicated through the associatedCSI-RS within the upper-level signaling SRS-ResourceSet. For non-codebook-based transmission, the UE does not expect the upper-level signaling spatialRelationInfo for the SRS resource and the associatedCSI-RS within the upper-level signaling SRS-ResourceSet to be configured together.

[0072] When multiple SRS resources are configured, the UE can determine the precoder and transmission rank to be applied to PUSCH transmission based on the SRI indicated by the base station. At this time, the SRI can be indicated through the SRS resource indicator field in the DCI or can be configured through the srs-ResourceIndicator, which is a higher-level signaling. Similar to the codebook-based PUSCH transmission described above, when the UE receives an SRI through the DCI, the SRS resource indicated by the SRI refers to the SRS resource corresponding to the SRI among the SRS resources transmitted before the PDCCH containing the SRI. The UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be simultaneously transmitted in the same symbol within one SRS resource set and the maximum number of SRS resources are determined by the UE capability reported by the UE to the base station. At this time, the SRS resources that the UE simultaneously transmits occupy the same RB. The UE configures one SRS port for each SRS resource. Only one SRS resource set with the usage value set to 'nonCodebook' in the upper signaling SRS-ResourceSet can be set, and up to four SRS resources for non-codebook based PUSCH transmission can be set.

[0073] The base station transmits one NZP-CSI-RS associated with an SRS resource set to the terminal, and the terminal calculates a precoder to be used when transmitting one or more SRS resources within the SRS resource set based on the result measured upon reception of the NZP-CSI-RS. When the terminal transmits one or more SRS resources within the SRS resource set with usage set to 'nonCodebook' to the base station, the terminal applies the calculated precoder, and the base station selects one or more SRS resources from the received one or more SRS resources. At this time, in non-codebook based PUSCH transmission, the SRI represents an index that can express a combination of one or more SRS resources, and the SRI is included in the DCI. At this time, the number of SRS resources indicated by the SRI transmitted by the base station can be the number of transmission layers of the PUSCH, and the terminal transmits the PUSCH by applying the precoder applied to SRS resource transmission to each layer.

[0074] [PUSCH: Repetitive Transmission Related]

[0075] The following describes in detail the repetitive transmission of uplink data channels in 5G systems. 5G systems support two types of repetitive transmission methods for uplink data channels: PUSCH repetitive transmission type A and PUSCH repetitive transmission type B. A terminal can be configured with either PUSCH repetitive transmission type A or B via upper layer signaling.

[0076] 1. PUSCH Repetitive Transmission Type A

[0077] As described above, the symbol length and the position of the start symbol of the uplink data channel are determined by a time domain resource allocation method within one slot, and the base station can notify the terminal of the number of repeated transmissions through upper layer signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0078] The terminal can repeatedly transmit an uplink data channel with the same length and start symbol as the uplink data channel set based on the number of repeated transmissions received from the base station in consecutive slots. In this case, if at least one symbol among the slots set by the base station to the terminal as downlink or the symbols of the uplink data channel set to the terminal is set as downlink, the terminal skips the uplink data channel transmission, but counts the number of repeated transmissions of the uplink data channel.

[0079] 2. PUSCH Repetitive Transmission Type B

[0080] As described above, the start symbol and length of the uplink data channel are determined by a time domain resource allocation method within one slot, and the base station can notify the terminal of the number of repetitions through upper signaling (e.g., RRC signaling) or L1 signaling (e.g., DCI).

[0081] First, the nominal repetition of the uplink data channel is determined based on the start symbol and length of the established uplink data channel as follows. The slot where the nth nominal repetition starts is The symbol given by and starting from that slot is is given by . The slot where the nth nominal repetition ends is The symbol given by and ending in that slot is is given by . Here, n=0, ..., numberofrepetitions-1, S represents the start symbol of the established uplink data channel, and L represents the symbol length of the established uplink data channel. indicates the slot in which the PUSCH transmission starts. represents the number of symbols per slot.

[0082] The UE determines an invalid symbol for PUSCH repetition transmission type B. A symbol configured for downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated is determined as an invalid symbol for PUSCH repetition transmission type B. Additionally, an invalid symbol can be configured in a higher layer parameter (e.g., InvalidSymbolPattern). The higher layer parameter (e.g., InvalidSymbolPattern) provides a symbol-level bitmap spanning one or two slots, where an invalid symbol can be configured. 1 in the bitmap indicates an invalid symbol. Additionally, the period and pattern of the bitmap can be configured through a higher layer parameter (e.g., periodicityAndPattern). If a higher layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter indicates 1, the terminal applies an invalid symbol pattern, and if the parameter indicates 0, the terminal does not apply the invalid symbol pattern. If a higher layer parameter (e.g., InvalidSymbolPattern) is set and the InvalidSymbolPatternIndicator-ForDCIFormat0_1 or InvalidSymbolPatternIndicator-ForDCIFormat0_2 parameter is not set, the terminal applies an invalid symbol pattern.

[0083] After determining invalid symbols, the terminal may consider symbols other than invalid symbols as valid symbols for each nominal repetition. If each nominal repetition includes at least one valid symbol, the nominal repetition may include one or more actual repetitions. Here, each actual repetition includes a contiguous set of valid symbols that can be used for PUSCH repetitive transmission type B within a single slot.

[0084] FIG. 1 is a diagram illustrating an example of PUSCH repetition transmission type B in a wireless communication system according to one embodiment of the present disclosure.

[0085] The terminal may set the start symbol S of the uplink data channel to 0, the length L of the uplink data channel to 14, and the number of repeated transmissions to 16. In this case, the nominal repetition is indicated in 16 consecutive slots (701). After that, the terminal may determine that the symbol set as the downlink symbol in each nominal repetition (701) is an invalid symbol. In addition, the terminal determines that the symbols set to 1 in the invalid symbol pattern (702) are invalid symbols. In each nominal repetition, if valid symbols that are not invalid symbols are composed of one or more consecutive symbols in one slot, they are set to the actual repetition and transmitted (703).

[0086] Additionally, for PUSCH repetitive transmissions, NR Release 16 can define the following additional methods for UL grant-based PUSCH transmissions across slot boundaries and configured grant-based PUSCH transmissions:

[0087] - Method 1 (mini-slot level repetition): Two or more PUSCH repetitive transmissions are scheduled within a slot or across the boundaries of consecutive slots through a single UL grant. In addition, for Method 1, the time-domain resource allocation information in the DCI indicates the resources of the first repetitive transmission. In addition, the time-domain resource information of the first repetitive transmission and the time-domain resource information of the remaining repetitive transmissions can be determined based on the uplink or downlink direction determined for each symbol in each slot. Each repetitive transmission occupies consecutive symbols.

[0088] - Method 2 (multi-segment transmission): Two or more repeated PUSCH transmissions are scheduled in consecutive slots through a single UL grant. At this time, one transmission is designated for each slot, and each transmission may have a different starting point or repetition length. In addition, in Method 2, the time-domain resource allocation information in the DCI indicates the starting point and repetition length of all repeated transmissions. In addition, when performing repeated transmissions in a single slot through Method 2, if there are multiple sets of consecutive uplink symbols in the slot, each repeated transmission is performed for each set of uplink symbols. If there is only one set of consecutive uplink symbols in the slot, one repeated PUSCH transmission is performed according to the method of NR Release 15.

[0089] - Method 3: Two or more repeated PUSCH transmissions are scheduled in consecutive slots via two or more UL grants. In this case, one transmission is designated for each slot, and the nth UL grant can be received before the PUSCH transmission scheduled for the n-1th UL grant ends.

[0090] - Method 4: One or more PUSCH repetitive transmissions within a single slot, or two or more PUSCH repetitive transmissions across the boundaries of consecutive slots, can be supported through one UL grant or one configured grant. The number of repetitions indicated by the base station to the terminal is only a nominal value, and the number of PUSCH repetitive transmissions actually performed by the terminal may be greater than the nominal number of repetitions. The time-domain resource allocation information in the DCI or the configured grant indicates the resources of the first repetitive transmission indicated by the base station. The time-domain resource information of the remaining repetitive transmissions can be determined with reference to at least the resource information of the first repetitive transmission and the uplink or downlink direction of the symbols. If the time-domain resource information of the repetitive transmission indicated by the base station crosses a slot boundary or includes an uplink / downlink switchover point, the repetitive transmission can be divided into multiple repetitive transmissions. In this case, one repetitive transmission can be included for each uplink period within one slot.

[0091] [SRS related]

[0092] Next, we describe an uplink channel estimation method using the Sounding Reference Signal (SRS) transmission of a terminal. The base station can configure at least one SRS configuration for each uplink BWP to convey configuration information for SRS transmission to the terminal, and can also configure at least one SRS resource set for each SRS configuration. For example, the base station and the terminal can exchange the following upper-level signaling information to convey information regarding the SRS resource set.

[0093] - srs-ResourceSetId: SRS resource set index

[0094] - srs-ResourceIdList: A set of SRS resource indices referenced in the SRS resource set.

[0095] - resourceType: This is the time axis transmission setting of the SRS resource referenced in the SRS resource set, and can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. If set to 'periodic' or 'semi-persistent', associated CSI-RS information can be provided depending on the usage of the SRS resource set. If set to 'aperiodic', an aperiodic SRS resource trigger list and slot offset information can be provided, and associated CSI-RS information can be provided depending on the usage of the SRS resource set.

[0096] - usage: This is a setting for the usage of the SRS resource referenced in the SRS resource set, and can be set to one of 'beamManagement', 'codebook', 'nonCodebook', and 'antennaSwitching'.

[0097] - alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter settings for adjusting the transmission power of the SRS resource referenced in the SRS resource set.

[0098] The terminal can understand that the SRS resource included in the set of SRS resource indices referenced in the SRS resource set follows the information set in the SRS resource set.

[0099] In addition, the base station and the terminal can transmit and receive upper layer signaling information to convey individual configuration information for the SRS resource. For example, the individual configuration information for the SRS resource can include time-frequency axis mapping information within the slot of the SRS resource, which can include information about frequency hopping within or between slots of the SRS resource. In addition, the individual configuration information for the SRS resource can include the time axis transmission configuration of the SRS resource, which can be set to one of 'periodic', 'semi-persistent', and 'aperiodic'. This can be restricted to have the same time axis transmission configuration as the SRS resource set including the SRS resource. If the time axis transmission configuration of the SRS resource is set to 'periodic' or 'semi-persistent', the SRS resource transmission period and slot offset (e.g., periodicityAndOffset) can additionally be included in the time axis transmission configuration.

[0100] The base station can activate, deactivate, or trigger SRS transmission to the UE through higher layer signaling, including RRC signaling or MAC CE signaling, or L1 signaling (e.g., DCI). For example, the base station can activate or deactivate periodic SRS transmission to the UE through higher layer signaling. The base station can instruct the UE to activate an SRS resource set with resourceType set to periodic through higher layer signaling, and the UE can transmit an SRS resource referenced in the activated SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information set in the SRS resource, and the slot mapping, including the transmission period and slot offset, follows the periodicityAndOffset set in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information set in the SRS resource, or the associated CSI-RS information set in the SRS resource set that includes the SRS resource. A terminal can transmit SRS resources within an activated uplink BWP for periodic SRS resources activated through upper layer signaling.

[0101] For example, a base station can activate or deactivate semi-persistent SRS transmission to a terminal through upper layer signaling. The base station can instruct the terminal to activate an SRS resource set through MAC CE signaling, and the terminal can transmit an SRS resource referenced in the activated SRS resource set. The SRS resource set activated through MAC CE signaling can be limited to an SRS resource set with resourceType set to semi-persistent. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource, and the slot mapping including the transmission period and slot offset follows the periodicityAndOffset configured in the SRS resource. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information configured in the SRS resource, or the associated CSI-RS information configured in the SRS resource set that includes the SRS resource. If spatial relation info is configured in an SRS resource, the spatial domain transmission filter can be determined by referring to the configuration information for spatial relation info transmitted through MAC CE signaling that activates semi-persistent SRS transmission without following it. The terminal can transmit SRS resources within the activated uplink BWP for the semi-persistent SRS resource activated through upper layer signaling.

[0102] For example, a base station can trigger aperiodic SRS transmission to a terminal via DCI. The base station can indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) via the SRS request field of the DCI. The terminal can understand that an SRS resource set including the aperiodic SRS resource trigger indicated via DCI in the aperiodic SRS resource trigger list among the configuration information of the SRS resource set has been triggered. The terminal can transmit an SRS resource referenced in the triggered SRS resource set. The time-frequency domain resource mapping within the slot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource. In addition, the slot mapping of the transmitted SRS resource can be determined through a slot offset between a PDCCH including the DCI and the SRS resource, which can refer to value(s) included in a slot offset set configured in the SRS resource set.

[0103] Specifically, the slot offset between the PDCCH including DCI and the SRS resource can be applied by applying the value indicated in the time domain resource assignment field of the DCI among the offset value(s) included in the slot offset set configured in the SRS resource set. In addition, the spatial domain transmission filter applied to the transmitted SRS resource can refer to the spatial relation information configured in the SRS resource, or can refer to the associated CSI-RS information configured in the SRS resource set including the SRS resource. The UE can transmit the SRS resource within the activated uplink BWP for the aperiodic SRS resource triggered through the DCI.

[0104] When a base station triggers aperiodic SRS transmission to a terminal through DCI, a minimum time interval may be required between a PDCCH including the DCI that triggers aperiodic SRS transmission and the SRS to be transmitted, so that the terminal can transmit the SRS by applying configuration information for the SRS resource. The time interval for SRS transmission of the terminal can be defined as the number of symbols between the last symbol of the PDCCH including the DCI that triggers aperiodic SRS transmission and the first symbol to which the first SRS resource to be transmitted among the SRS resource(s) is mapped. The minimum time interval can be determined with reference to the PUSCH preparation procedure time required for the terminal to prepare for PUSCH transmission. In addition, the minimum time interval can have different values ​​depending on the usage of the SRS resource set including the SRS resource to be transmitted. For example, the minimum time interval can be determined as N2 symbols, which are defined by considering the terminal processing ability according to the capability of the terminal with reference to the PUSCH preparation procedure time of the terminal. In addition, considering the usage of the SRS resource set including the SRS resource being transmitted, if the usage of the SRS resource set is set to 'codebook' or 'antennaSwitching', the minimum time interval can be set to N2 symbols, and if the usage of the SRS resource set is set to 'nonCodebook' or 'beamManagement', the minimum time interval can be set to N2+14 symbols.The terminal may transmit an aperiodic SRS if the time interval for aperiodic SRS transmission is greater than or equal to the minimum time interval, and may ignore the DCI that triggers the aperiodic SRS if the time interval for aperiodic SRS transmission is less than the minimum time interval.

[0105] [Table 7]

[0106]

[0107]

[0108] The spatialRelationInfo setting information in [Table 7] above refers to a single reference signal and applies the beam information of the reference signal to the beam used for the corresponding SRS transmission. For example, the spatialRelationInfo setting may include information such as [Table 8] below.

[0109] [Table 8]

[0110]

[0111] Referring to the above spatialRelationInfo setting, the index of the reference signal to be referenced in order to use the beam information of a specific reference signal, i.e., the SS / PBCH block index, CSI-RS index, or SRS index can be set. The upper signaling referenceSignal is setting information indicating which beam information of which reference signal is to be referenced for the corresponding SRS transmission, ssb-Index means the index of the SS / PBCH block, csi-RS-Index means the index of the CSI-RS, and srs means the index of the SRS, respectively. If the value of the upper signaling referenceSignal is set to 'ssb-Index', the terminal can apply the reception beam used when receiving the SS / PBCH block corresponding to the ssb-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'csi-RS-Index', the terminal can apply the reception beam used when receiving the CSI-RS corresponding to the csi-RS-Index as the transmission beam of the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'srs', the terminal can apply the transmission beam used when transmitting the SRS corresponding to the srs as the transmission beam for the corresponding SRS transmission.

[0112] [Uplink PTRS related]

[0113] The terminal may set the phaseTrackingRS, which is an upper layer parameter for PTRS, on the upper layer parameter DMRS-UplinkConfig. When transmitting a PUSCH to a base station, the terminal may transmit a phase tracking reference signal (PTRS) for phase tracking for an uplink channel. The procedure for transmitting the UL PTRS by the terminal may be determined depending on whether transform precoding is performed when transmitting the PUSCH. When transform precoding is performed and the transformPrecoderEnabled field is set in the upper layer parameter PTRS-UplinkConfig, the sampleDensity in the transformPrecoderEnabled field may indicate the sample density threshold represented by NRB0 to NRB4 in the table below. When transform precoding is performed and the transformPrecoderEnabled field is set in the upper layer parameter PTRS-UplinkConfig, the terminal may determine the PT-RS group pattern for the scheduled resource NRB according to [Table 9]. Additionally, if a transform precoder is applied to PUSCH transmission, the number of bits in the PTRS-DMRS association area for indicating the association between PTRS and DMRS in DCI format 0_1 ​​or 0_2 may be 0.

[0114] [Table 9]

[0115]

[0116] When transform precoding is not applied to PUSCH transmission and the upper layer parameter phaseTrackingRS is configured, the UE may indicate NRB0 to NRB1 for frequecyDensity and ptrs-MCS1 to ptrs-MCS3 for timeDensity in the transformPrecoderDisabled field of the upper layer parameter PTRS-UplinkConfig. The UE may determine the PT-RS density in the time domain (LPT-RS) and the PT-RS density in the frequency domain (KPT-RS) as described in [Table 10] and [Table 11] according to the MCS (lMCS) and RB (NRB) of the scheduled PUSCH. In [Table 10], ptrs-MCS4 is not specified as a higher layer parameter, but the base station and the UE can know that it is 29 or 28 according to the configured MCS table.

[0117] [Table 10]

[0118]

[0119] [Table 11]

[0120]

[0121] When the transform precoder is not applied to PUSCH transmission and PTRS-UplinkConfig is configured, the base station may indicate a 2-bit 'PTRS-DMRS association' region to the UE to indicate the association between PTRS and DMRS in DCI format 0_1 ​​or 0_2. The indicated 2-bit PTRS-DMRS association region may be applied to [Table 12] or [Table 13] according to the maximum number of PTRS ports set by maxNrofPorts in the upper layer parameter PTRS-UplinkConfig. If the maximum number of PTRS ports is 1, the UE may determine the association between PTRS and DMRS with the 2-bit indicated by [Table 12] and the PTRS-DMRS association region, and transmit PTRS according to the determined association. When the maximum number of PTRS ports is 2, the terminal can determine the association between PTRS and DMRS with 2 bits indicated in the PTRS-DMRS association area in [Table 13], and transmit PTRS according to the determined association.

[0122] [Table 12]

[0123]

[0124] [Table 13]

[0125]

[0126] The DMRS ports in [Table 12] and [Table 13] can be determined through a table determined by the 'Antenna ports' area indicated by the same DCI as the DCI indicating the PTRS-DMRS association and the upper layer parameter settings. If the transform precoder is not set as the upper setting of the PUSCH, dmrs-Type is set to 1 and maxLength is set to 2 for DMRS, and the rank of the PUSCH is 2, the UE can determine the DMRS port through the table for 'Antenna port(s)' as in [Table 14] and the bits indicated by the Antenna ports area. If a noncodebook-based PUSCH is supported, the UE can determine the rank value by referring to the SRI area indicated by the same DCI including the 'Antenna ports' area (i.e., if the SRI area does not exist, the Rank can be regarded as 1). When supporting Codebook-based PUSCH, the UE can determine the rank value by referring to the TPMI area indicated by the same DCI as the DCI including the 'Antenna ports' area. [Table 14] is an example of the Antenna port table referenced when configuring the PUSCH described above. If the PUSCH is configured with other parameters, the DMRS port can be determined based on the bits in the Antenna port table according to the configuration and the Antenna ports area indicated by the DCI.

[0127] [Table 14]

[0128]

[0129] The 1st scheduled DMRS to the 4th scheduled DMRS in [Table 14] can be defined as values ​​that sequentially map the bits in the Antenna ports area of ​​the DCI and the DMRS ports indicated by the antenna port table according to the upper layer settings. For example, if the bits in the Antenna ports area of ​​the DCI are 0001 and the DMRS ports are determined by referring to the above [Table 14], the scheduled DMRS ports can be 0 and 1, and DMRS port 0 can be defined as the 1st scheduled DMRS, and DMRS port 1 can be defined as the 2nd scheduled DMRS. The bits in other Antenna ports areas and the DMRS ports determined by the antenna port table according to other upper layer settings can be applied similarly. The terminal can determine one DMRS port to associate the PTRS port by referring to the bits indicated by the PTRS-DMRS association in the DCI among the DMRS ports defined as above, and transmit the PTRS according to the determined DMRS port.

[0130] In [Table 13], the DMRS port sharing PTRS port 0 and the DMRS port sharing PTRS port 1 can be defined according to codebook-based PUSCH transmission or non-codebook-based PUSCH transmission. If the UE transmits PUSCH based on a partial-coherent or non-coherent codebook, the uplink layer transmitted to PUSCH antenna ports 1000 and 1002 is associated with PTRS port 0, and the uplink layer transmitted to PUSCH antenna ports 1001 and 1003 is associated with PTRS port 1. To explain with a more specific example, if layer 3: TPMI = 2 is selected for codebook-based PUSCH transmission, the first layer is associated with PTRS port 0 because it is transmitted to PUSCH antenna ports 1000 and 1002, the second layer is associated with PTRS port 1001, and the third layer is associated with PTRS port 1 because it is transmitted to PUSCH antenna port 1002. Each of the three layers represents a DMRS port, and the DMRS port for the first layer corresponds to '1st DMRS port which shares PTRS port 0' in [Table 28], the DMRS port for the second layer corresponds to '1st DMRS port which shares PTRS port 1' in [Table 28], and the DMRS port for the third layer corresponds to '2nd DMRS port which shares PTRS port 1' in [Table 28]. Similarly, the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1 can be determined based on different layer counts and TPMIs.

[0131] If the UE transmits a PUSCH based on a non-codebook, the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1 can be distinguished according to the SRI and antenna ports indicated by the DCI. More specifically, the SRS resource included in the SRS resource set with usage of 'nonCodebook' is set to be associated with PTRS port 0 or PTRS port 1 through the upper layer parameter ptrs-PortIndex. The base station indicates the SRS resource for transmitting a non-codebook based PUSCH using the SRI. At this time, the port of each indicated SRS resource is mapped one-to-one with each PUSCH DMRS port. The association between the PUSCH DMRS port and the PTRS port is determined according to the upper layer parameter ptrs-PortIndex of the SRS resource mapped to the DMRS port. To explain with a more specific example, let's assume that ptrs-PortIndex is set to n0, n0, n1, n1 for SRS resources 1 to 4 included in an SRS resource set whose usage is nonCodebook. Let's also assume that PUSCH is transmitted through SRS resources 1, 2, and 4 with SRI, and DMRS ports 0, 1, and 2 are indicated as antenna ports area. The ports of SRS resources 1, 2, and 4 are mapped to DMRS ports 0, 1, and 2, respectively. And according to ptrs-PortIndex in the SRS resource, DMRS ports 0 and 1 are associated with PTRS port 0, and DMRS port 2 is associated with PTRS port 1.Therefore, in [Table 28], DMRS port 0 corresponds to the '1st DMRS port which shares PTRS port 0', DMRS port 1 corresponds to the '2nd DMRS port which shares PTRS port 0', and DMRS port 2 corresponds to the '1st DMRS port which shares PTRS port 1'. Similarly, the DMRS port associated with PTRS port 0 and the DMRS port associated with PTRS port 1 can be determined by different SRI values ​​and ptrs-PortIndex setting methods in different patterns of SRS resources. The terminal determines the association between the DMRS ports and the PTRS ports as described above for the two PTRS ports. Thereafter, the terminal refers to the MSB bit of the PTRS-DMRS association among multiple DMRS ports having an association for each PTRS port to determine the DMRS port to be associated with PTRS port 0, and refers to the LSB bit to determine the DMRS port to be associated with PTRS port 1, and transmits the PTRS.

[0132] [SRS: How to set comb offset / cyclic shift]

[0133] Next, we describe how to set comb offset and cyclic shift when transmitting the Sounding Reference Signal (SRS) of the terminal.

[0134] The terminal can be configured with SRS resources from the base station through upper layer signaling, SRS-Resource or SRS-PosResource, and can be configured with the following items.

[0135] For SRS-Resource, the terminal can set the number of antenna ports for each SRS resource, and the value is It can be defined as and can be set through upper layer signaling nrofSRS-Ports or nrofSRS-Ports-n8. If the upper layer signaling usage in SRS-ResourceSet is set to a value other than nonCodebook, can mean the number of the i-th antenna port, and i is 0 to -1 can be an integer. If the upper layer signaling usage within the SRS-ResourceSet is set to nonCodebook, each SRS resource =1 antenna port can be set, and the antenna port of the i+1th SRS resource in the SRS-ResourceSet can be defined as SRS-PosResource. = can be defined as 1.

[0136] The terminal can be configured for the number of consecutive symbols in which the SRS is transmitted through nrofSymbols in resourceMapping, which is an upper layer signaling from the base station, and the value is can be defined as

[0137] The terminal can be configured for the position of the start symbol where the SRS is transmitted within a slot through the startPosition in the resourceMapping, which is an upper layer signaling from the base station, and the value is can be defined as . At this time, can mean the number of symbols in the slot, and its value can be 14 for the normal cyclic prefix or 12 for the extended cyclic prefix. can mean an offset value that counts the number of symbols backwards from the symbol located at the very end of the slot. At this time, can satisfy.

[0138] may mean the starting position of the frequency resource where the SRS is transmitted.

[0139] An SRS sequence that can be generated through an SRS resource defined based on the above information can be defined as in [Mathematical Formula 1] below.

[0140] [Mathematical Formula 1]

[0141]

[0142] At this time, means the length of the SRS sequence. is determined through [Table 16] below, and can be determined through upper layer signaling b-SRS and c-SRS. In this case, when b-SRS is set, in [Table 16] below, You can determine the value, The value of b, which is a subscript of , can be determined, and if b-SRS is not set, It can be. c-SRS is in [Table 16] below. You can determine the value. can be determined via FreqScalingFactor, which is a higher layer signaling, and if that parameter is not set, It can be. The terminal can expect the length of the SRS sequence to be a multiple of 6 when the upper layer signaling FreqScalingFactor is set.

[0143] can be defined as, can determine the size of the comb. At this time, the size of the comb can mean the interval between REs where the SRS is transmitted on the frequency resource. For example, the size of the comb This may mean that the spacing between REs where SRS is transmitted is 2 REs. The terminal can be configured for the size of the Comb through the upper layer signaling, transmissionComb. may mean the symbol index within the symbols in which the SRS resource is transmitted. The terminal The maximum cyclic shift value is It can be determined as shown in [Table 15].

[0144] [Table 15]

[0145]

[0146] means the cyclic shift of the i-th antenna port. And the basic sequence is It can be defined as follows:

[0147]

[0148] At this time, can mean the length of the SRS sequence. For one base sequence, different and Multiple SRS sequences can be generated depending on the value.

[0149] Multiple base sequences can be divided into groups, and the indices of the groups are can be defined as {0,1,...,29}, and v can mean the index of the basic sequence within the group. If In this case, each group can contain one base sequence, and in this case It could be. If In this case, each group can contain two base sequences, and in this case It could be. The definition of is the length of the sequence It may vary depending on the value of .

[0150] If the length of the basic sequence is 36 or more, i.e. When the basic sequence can be defined as follows. At this time, Is It can be the largest prime number smaller than .

[0151]

[0152] If the length of the basic sequence is 6, 12, 18, 24, i.e. If the length of the basic sequence is 6, 12, 18, 24, i.e. can be defined as follows.

[0153]

[0154] At this time, The value can be defined through [Table 17] to [Table 20] below.

[0155] If the length of the base sequence is 30, i.e. When the basic sequence can be defined as follows.

[0156]

[0157] If the terminal has the upper layer signaling nrofSRS-Ports-n8 set to ports8tdm, can be defined as follows, otherwise can be defined as

[0158] if And If, can be defined as

[0159] if And If, can be defined as

[0160] When neither of the above cases is true, can be defined as

[0161] antenna port which means the cyclic shift corresponding to can be defined as follows.

[0162]

[0163] At this time, can be defined as follows.

[0164] And When, can be defined as

[0165] And This or that, When, can be defined as

[0166] When neither of the above cases is true, can be defined as

[0167] At this time, is a parameter that determines the cyclic shift value, which can be set through cyclicShift-n2, cyclicShift-n4, or cyclicShift-n8 in the upper layer signaling transmissionComb. can be determined through the above [Table 15].

[0168] and can be determined as follows.

[0169] If the upper layer signaling nrofSRS-Ports-n8 is set to ports8tdm, can be defined as, In case of If is defined as, If can be defined as follows. That is, when a terminal transmits in TDM mode for an SRS resource consisting of 8 antenna ports, the antenna port to be transmitted in the first symbol is =For 1000, 1001, 1004, 1005 respectively Defined as 1000, 1001, 1002, 1003, which are the antenna ports to be transmitted in the second symbol. =For 1002, 1003, 1006, 1007 respectively By defining them as 1000, 1001, 1002, and 1003, the resource allocation method for the SRS resource consisting of 4 antenna ports can be applied as is when allocating resources for 4 different antenna ports transmitted in each symbol.

[0170] Except for the above cases, i.e. when the upper layer signaling nrofSRS-Ports-n8 is not set to ports8tdm, and can be defined as

[0171] It means the starting position in the frequency dimension of the SRS corresponding to the i-th antenna port. can be defined as follows.

[0172]

[0173] At this time, can be defined as follows.

[0174]

[0175] At this time, can be defined as follows.

[0176] If, can be defined as

[0177] If, can be defined as

[0178] If, can be defined as

[0179] If, can be defined as

[0180] If, can be defined as

[0181] If, can be defined as

[0182] If, can be defined as

[0183] For all other cases except the above, can be defined as

[0184] At this time, can be defined as follows.

[0185]

[0186] At this time, can be defined as follows.

[0187]

[0188] can be set to StartRBIndex, which is a higher layer signaling, and if not set, can be defined as

[0189] For cases where the upper layer signaling EnableStartRBHopping is set, the following and Based on the value, it can be determined through [Table 21], otherwise can be defined as

[0190]

[0191] If SRS transmission is performed based on SRS-PosResource, the above can be defined based on [Table 22] below, otherwise (if SRS transmission is performed based on SRS-Resource), can be defined as

[0192] The offset value in the frequency dimension is is a value that determines how far the SRS is transmitted in the frequency dimension from the reference position, and can be set through the upper layer signaling freqDomainShift. Comb offset value is indicated. can be set via combOffset-n2, combOffset -n4, or combOffset -n8 in the upper layer signaling transmissionComb.

[0193] As a higher layer signaling related to frequency hopping of SRS, b-hop within freqHoping can be set, and can be defined as

[0194] is a value representing the index of the frequency position, and can be defined as follows.

[0195] if In this case, frequency hopping of SRS is not supported, and the index of frequency position is indicated. is all A symbol can have a constant value during a period and can be defined as follows:

[0196]

[0197] At this time, is a value set through the upper layer signaling freqDomainPosition, and if not set, the value can be 0.

[0198] if In this case, frequency hopping of SRS is supported, can be defined as follows.

[0199] if If, can be defined as follows.

[0200] If not, can be defined as follows.

[0201] At this time, is if If is even, can be defined as, and if If is odd, can be defined as silver It can be defined as 1 regardless of the value.

[0202] can be defined as a parameter that counts the number of SRS transmissions. If the terminal transmits an aperiodic SRS resource, the number of SRS transmissions within a specific slot Within the symbol can be defined as follows. At this time, s can be defined as s=2 if the upper layer signaling nrofSRS-Ports-n8 is set to ports8tdm, and s=1 otherwise. At this time, can be a value set by the repetitionFactor, which is a higher layer signaling, and if not set, can be defined as

[0203] If the terminal transmits periodic or semi-persistent SRS resources, In slots that satisfy can be defined as follows.

[0204]

[0205] At this time, and can mean the period and slot offset of a periodic or semi-persistent SRS, respectively.

[0206] FIG. 2 is a diagram illustrating a method for allocating comb offset and cyclic shift during SRS transmission according to an embodiment of the present disclosure.

[0207] In the first example (800), the terminal has an SRS resource consisting of four antenna ports. (comb offset value), (cyclic shift value), (comb size value) and We can assume a situation where (maximum cyclic shift value) is set. In this case, the terminal =1000 and 1002 are the cyclic shift values ​​assigned to each and can be defined as, =Comb offset values ​​for both 1000 and 1002 can be defined (805). Also, the terminal = cyclic shift values ​​assigned for 1001 and 1003 respectively and can be defined as, = Comb offset values ​​for both 1001 and 1003 can be defined as (810). Therefore, two antenna ports among the four antenna ports are assigned to the same comb offset, and in order to separate the two antenna ports within the same comb offset, the interval between the cyclic shift values ​​corresponding to the two antenna ports is set to the maximum. can be decided by

[0208] In the second example (830), the terminal has an SRS resource consisting of four antenna ports. (comb offset value), (cyclic shift value), (comb size value) and We can assume a situation where (maximum cyclic shift value) is set. In this case, the terminal =1000, 1001, 1002 and 1003 are the cyclic shift values ​​assigned to each can be defined as, = Comb offset values ​​for all 1000, 1001, 1002, and 1003 can be defined as (835). Therefore, all four antenna ports are assigned to the same comb offset, and in order to separate the four antenna ports within the same comb offset, the interval between the cyclic shift values ​​corresponding to the four antenna ports is set to the maximum. can be decided by

[0209] In the third example (860), the terminal has an SRS resource consisting of four antenna ports. (comb offset value), (cyclic shift value), (comb size value) and We can assume a situation where (maximum cyclic shift value) is set. In this case, the terminal = cyclic shift values ​​assigned for 1000 and 1002 respectively and can be defined as, = Comb offset values ​​for both 1000 and 1002 can be defined as (865). In addition, the terminal = cyclic shift values ​​assigned for 1001 and 1003 respectively and can be defined as, = Comb offset values ​​for both 1001 and 1003 can be defined as (870). Therefore, two antenna ports among the four antenna ports are assigned to the same comb offset, and in order to separate the two antenna ports within the same comb offset, the interval between the cyclic shift values ​​corresponding to the two antenna ports is set to the maximum. can be decided by

[0210] [Table 16]

[0211]

[0212]

[0213] [Table 17]

[0214]

[0215] [Table 18]

[0216]

[0217] [Table 19]

[0218]

[0219] [Table 20]

[0220]

[0221] [Table 21]

[0222]

[0223] [Table 22]

[0224]

[0225] [Regarding terminal capability reporting]

[0226] In LTE and NR, a terminal, while connected to a serving base station, can perform a procedure to report its supported capabilities to the base station. In the description below, this is referred to as a UE capability report.

[0227] A base station can transmit a UE capability inquiry message requesting a capability report to a connected terminal. The message can include a UE capability request for each RAT (radio access technology) type of the base station. The RAT type-specific request can include information on a combination of supported frequency bands, etc. In addition, in the case of the UE capability inquiry message, UE capabilities for multiple RAT types can be requested through a single RRC message container transmitted by the base station, or the base station can include multiple UE capability inquiry messages including UE capability requests for each RAT type and transmit them to the terminal. That is, the UE capability inquiry can be repeated multiple times in one message, and the terminal can compose a corresponding UE capability information message and report it multiple times. In the next-generation mobile communication system, a UE capability request can be made for MR-DC (Multi-RAT dual connectivity), including NR, LTE, and EN-DC (E-UTRA - NR dual connectivity). Additionally, the terminal capability inquiry message is typically transmitted initially after the terminal is connected to the base station, but the base station may request it under any conditions when necessary.

[0228] In the above step, the terminal that receives the UE capability report request from the base station configures the terminal capability based on the RAT type and band information requested from the base station. Below is a summary of how the terminal configures the UE capability in the NR system.

[0229] 1. If the UE receives a list of LTE and / or NR bands through a UE capability request from the base station, the UE configures a band combination (BC) for EN-DC and NR stand-alone (SA). That is, it configures a candidate list of BCs for EN-DC and NR SA based on the bands requested to the base station via FreqBandList. Furthermore, the bands are prioritized in the order listed in FreqBandList.

[0230] 2. If the base station requests UE capability reporting by setting the "eutra-nr-only" flag or the "eutra" flag, the UE completely removes NR SA BCs from the list of configured BC candidates. This operation can only occur when the LTE base station (eNB) requests the "eutra" capability.

[0231] 3. The terminal then removes fallback BCs from the BC candidate list constructed in the above step. Here, a fallback BC is a BC obtained by removing at least one band corresponding to an SCell from a random BC. This step can be omitted because the BC before removing the band corresponding to at least one SCell can already cover the fallback BC. This step also applies to MR-DC, i.e., to LTE bands. The BCs remaining after this step are the final "candidate BC list."

[0232] 4. The terminal selects BCs to report by selecting BCs that match the requested RAT type from the final "candidate BC list" above. In this step, the terminal constructs the supportedBandCombinationList in a set order. That is, the terminal constructs BCs and UE capabilities to report according to the preset rat-Type order (nr -> eutra-nr -> eutra). In addition, it constructs a featureSetCombination for the constructed supportedBandCombinationList, and constructs a list of "candidate feature set combinations" from the candidate BC list after removing the list for the fallback BC (which contains capabilities of the same or lower level). The "candidate feature set combinations" above include feature set combinations for both NR and EUTRA-NR BCs, and can be obtained from the feature set combinations in the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0233] 5. Also, if the requested rat Type is eutra-nr and has an effect, featureSetCombinations are included in both containers: UE-MRDC-Capabilities and UE-NR-Capabilities. However, the NR feature set is included only in UE-NR-Capabilities.

[0234] After terminal capabilities are configured, the terminal transmits a terminal capability information message containing the terminal capabilities to the base station. Based on the terminal capabilities received from the terminal, the base station then performs appropriate scheduling and transmission / reception management for the terminal.

[0235] <First embodiment: SRS support method for codebook use for a terminal supporting three transmission antennas>

[0236] As one embodiment of the present disclosure, a method for supporting SRS for codebook purposes for a terminal supporting three transmit antennas is described. This embodiment may operate in combination with at least one other embodiment described in the present disclosure.

[0237] As described above, the terminal can be configured with codebook for the upper layer signaling txConfig for codebook-based PUSCH transmission. In addition, the terminal can be configured with an SRS resource set in which the upper layer signaling usage is set with codebook from the base station, and the terminal can be configured with up to two SRS resources within the configured SRS resource set. In this case, the SRS resources that can be configured for a terminal supporting three transmit antennas to transmit a codebook-based PUSCH can be based on a combination of at least one of the methods described below.

[0238] [Method 1-1]

[0239] According to one embodiment of the present disclosure, a terminal may be configured with an SRS resource composed of four antenna ports in order to perform codebook-based PUSCH transmission through three antenna ports. More specifically, the terminal may expect that up to two SRS resources composed of four antenna ports are configured within an SRS resource set in which usage is set to codebook. That is, an SRS resource set in which usage is set to codebook may include up to two SRS resources composed of four antenna ports. In this case, the terminal may not perform transmission on one of the four antenna ports constituting the SRS resource. In this case, the one antenna port on which the terminal will not perform transmission may be determined as the last antenna port (for example, antenna port 1003) among the four antenna ports constituting (included in) the SRS resource. Alternatively, the antenna port on which the terminal will not perform transmission may be determined as the first antenna port (for example, antenna port 1000) among the four antenna ports constituting (included in) the SRS resource. Alternatively, the antenna port on which the terminal will not perform transmission may be determined as any antenna port that can be defined in the standard among the four antenna ports constituting (included in) the SRS resource (for example, antenna port 1002, or any one of antenna ports 1000 to 1003).Alternatively, one antenna port on which the terminal will not perform transmission may be determined as an antenna port determined by a combination of at least one of a higher layer signaling, MAC-CE signaling, and L1 signaling from the base station among the four antenna ports that constitute (or are included in) the SRS resource (for example, the antenna port 1002 may be set to not be transmitted by a higher layer signaling from the base station).

[0240] Hereinafter, in the present disclosure, the fact that a terminal does not transmit on a specific antenna port associated with an SRS resource may mean that the terminal does not transmit SRS on the specific antenna port. Furthermore, in the present disclosure, the fact that a specific antenna port associated with an SRS resource does not transmit may mean that the terminal does not transmit SRS on the specific antenna port.

[0241] Hereinafter, in the present disclosure, when a terminal transmits on a specific antenna port associated with an SRS resource, this may mean that the terminal transmits SRS on the specific antenna port. Furthermore, in the present disclosure, when a specific antenna port associated with an SRS resource transmits, this may mean that the terminal transmits SRS on the specific antenna port.

[0242] According to one embodiment of the present disclosure, when a terminal does not perform transmission on the last antenna port (e.g., antenna port 1003) for an SRS resource consisting of four antenna ports, the terminal can transmit an SRS on the allocated time and frequency resource (SRS resource) using only the comb offset and cyclic shift values ​​allocated to antenna ports 1000, 1001, and 1002, based on an SRS sequence generated based on the SRS resource. Since the antenna port related to the SRS transmitted by the terminal and the PUSCH antenna port that the base station can schedule based on the SRS transmitted by the terminal can be assumed to be the same by the terminal and the base station, in the case where there are up to three antenna ports of the PUSCH transmitted from the terminal, such as 1000, 1001, and 1002, considering three transmit antennas, for an SRS resource having four antenna ports, not transmitting on the last antenna port 1003 among the four antenna ports (not transmitting the SRS on the last antenna port 1003) may be the simplest method from the perspective of a single terminal and base station that can maintain a connection / association relationship between the SRS antenna port and the PUSCH antenna port. Here, the connection / association relationship between the SRS antenna port and the PUSCH antenna port may mean that the antenna port associated with the SRS transmitted by the terminal and the PUSCH antenna port that the base station can schedule based on the SRS transmitted by the terminal are the same. In this case, maintaining the connection / association relationship between the SRS antenna port and the PUSCH antenna port may mean that the port numbers of the antenna ports constituting the SRS antenna port and the port numbers of the antenna ports constituting the PUSCH antenna port are the same.For example, if the port numbers of the antenna ports constituting the SRS antenna port are 1000, 1001, and 1002, and the port numbers of the antenna ports constituting the PUSCH antenna port are also 1000, 1001, and 1002, the connection / association relationship between the SRS antenna port and the PUSCH antenna port may be maintained. As another example, if the port numbers of the antenna ports constituting the SRS antenna port are 1001, 1002, and 1003, and the port numbers of the antenna ports constituting the PUSCH antenna port are also 1000, 1001, and 1002, the connection / association relationship between the SRS antenna port and the PUSCH antenna port may not be maintained. Meanwhile, the fact that SRS transmission is not fixedly performed for a specific antenna port may hinder flexibility in terms of scheduling of the base station.

[0243] According to one embodiment of the present disclosure, if a terminal does not transmit an antenna port other than the last antenna port for an SRS resource composed of four antenna ports (i.e., if an SRS is not transmitted from an antenna port other than the last antenna port among the four antenna ports constituting the SRS resource), the terminal may readjust / reorder / renumber the numbers of the remaining antenna ports, excluding the antenna ports on which transmission is not performed, to 1000, 1001, and 1002. For example, if the terminal does not transmit on the first antenna port (e.g., antenna port 1000), the terminal may readjust / reorder / renumber the remaining antenna ports 1001, 1002, and 1003 to 1000, 1001, and 1002, respectively, generate an SRS sequence, and transmit an SRS on the allocated time and frequency resource (SRS resource) by using comb offset and cyclic shift values. As another example, if the terminal does not transmit on the second antenna port (e.g., antenna port 1001), the terminal may re-adjust / re-align / re-number the remaining antenna ports 1000, 1002, and 1003, such that 1002 becomes 1001 and 1003 becomes 1002. As another example, if the terminal does not transmit on the third antenna port (e.g., antenna port 1002), the terminal may re-adjust / re-align / re-number the remaining antenna ports 1000, 1001, and 1003, such that 1003 becomes 1002. As another example, if the terminal does not perform transmission on the fourth antenna port (e.g., antenna port 1003), the terminal may not perform recalibration / reordering / re-numbering since the remaining antenna ports are 1000, 1001, and 1002.Re-arranging antenna port numbers may be a way to maintain the connection / association relationship between SRS and PUSCH antenna ports, but from the perspective of allocating resources to multiple terminals at the base station, it may have the same effect as the method of not performing transmission on the last antenna port described above, and thus, similarly to the method described above, the scheduling flexibility of the base station may be hindered.

[0244] According to one embodiment of the present disclosure, if a terminal does not transmit on an antenna port other than the last antenna port for an SRS resource consisting of four antenna ports, the terminal may not readjust / reorder / re-number the numbers of the remaining antenna ports excluding the non-transmitting antenna ports to 1000, 1001, and 1002. For example, if the terminal does not transmit on the first antenna port (e.g., antenna port 1000), the terminal may generate an SRS sequence assuming that SRS is transmitted on the remaining antenna ports 1001, 1002, and 1003, and may perform transmission on the allocated time and frequency resource (SRS resource) using comb offset and cyclic shift values. In this case, the PUSCH antenna ports are 1000, 1001, and 1002, while the SRS antenna ports are 1001, 1002, and 1003, which breaks the assumption between the base station and the terminal that the PUSCH antenna ports and the SRS antenna ports are the same. Accordingly, it may be necessary to define additional connection relationships / associations between the PUSCH antenna ports and the SRS antenna ports. For example, a connection relationship may be defined in which the PUSCH antenna ports and the SRS antenna ports are each associated one-to-one in ascending order from the lowest antenna port number. That is, according to the additional connection relationship, when the individual connection relationship between ports is represented as (PUSCH antenna port ↔ SRS antenna port), the overall additional connection relationship may include individual connection relationships between ports such as (1000 ↔1001), (1001 ↔ 1002), and (1002 ↔ 1003). According to this embodiment, from the perspective of allocating resources to multiple terminals at a base station, it may be possible to flexibly allocate antenna ports of different terminals depending on the scheduling situation.

[0245] The above [Method 1-1] can be similarly applied not only to a terminal having three transmit antennas, but also to a terminal having five, six, and seven transmit antennas when defining an SRS resource to perform codebook-based PUSCH transmission. For example, when a terminal has five, six, and seven transmit antennas, it may not perform transmission on three, two, and one antenna ports, respectively, in an SRS resource consisting of eight antenna ports, and the method of not transmitting on one antenna port among the four antenna ports can be reused to select three, two, and one antenna ports, respectively.

[0246] [Method 1-2]

[0247] According to one embodiment of the present disclosure, a terminal may perform uplink channel estimation for three antenna ports by using one SRS resource configured with one antenna port and one SRS resource configured with two antenna ports, respectively, in order to perform codebook-based PUSCH transmission through three antenna ports. That is, the terminal may transmit an SRS to a base station through three antenna ports by using one SRS resource configured with one antenna port and one SRS resource configured with two antenna ports, and the base station may perform uplink channel estimation using the SRS transmitted through the three antenna ports. The terminal may consider an SRS resource configured with one antenna port and an SRS resource configured with two antenna ports as one SRS resource group within an SRS resource set in which usage is set to codebook, and the terminal may expect that up to two SRS resource groups including an SRS resource configured with one antenna port and an SRS resource configured with two antenna ports are configured. For example, if a terminal is configured with first and third SRS resources each consisting of one antenna port, and second and fourth SRS resources each consisting of two antenna ports, the terminal may consider the first and second SRS resources as a first SRS resource group and use them when estimating channels for three antenna ports, and may consider the third and fourth SRS resources as a second SRS resource group and use them when estimating channels for three antenna ports.

[0248] Instead of indicating SRS resources to the terminal through the SRI field in the DCI, the base station can indicate each SRS resource group to the terminal. For example, if the terminal is configured with the first to fourth SRS resources as described above, and the first and second SRS resources are defined as the first SRS resource group, and the third and fourth SRS resources are defined as the second SRS resource group, the terminal can assume that the first code point and the second code point of the SRI field indicate the first SRS resource group and the second SRS resource group, respectively.

[0249] [Method 1-3]

[0250] According to one embodiment of the present disclosure, a terminal may define an SRS resource composed of three antenna ports to perform uplink channel estimation for three antenna ports in order to perform codebook-based PUSCH transmission through three antenna ports. That is, an SRS resource composed of three antenna ports may be defined / configured, an SRS may be transmitted to a base station through the three antenna ports on one SRS resource composed of three antenna ports, and the base station may perform uplink channel estimation using the SRS transmitted through the three antenna ports on the one SRS resource. At this time, the three antenna ports that may be included in the corresponding SRS resource may be 1000, 1001, and 1002, respectively. The terminal may expect that up to two SRS resources composed of three antenna ports are configured within an SRS resource set in which usage is set to codebook. The terminal may be configured with one comb offset and one cyclic shift value that may be commonly applied to the three antenna ports. For example, when a first SRS resource including three antenna ports and a second SRS resource including three antenna ports are set, a first comb offset and a first cyclic shift value may be set for the three antenna ports included in the first SRS resource, and a second comb offset and a second cyclic shift value may be set for the three antenna ports included in the second SRS resource.

[0251] According to one embodiment of the present disclosure, the terminal has a comb size of 2 (e.g., , that is, by the above [Table 15] ), the comb offset and cyclic shift values ​​of antenna ports 1000, 1001, and 1002 can be determined using at least one combination of the embodiments below.

[0252] According to one embodiment of the present disclosure, the terminal If, can be defined as and at this time can be set by upper layer signaling. That is, the terminal can transmit by distinguishing three antenna ports 1000, 1001, and 1002 with different cyclic shift values ​​at the same RE location, so that excellent frequency resource allocation efficiency can be guaranteed. The terminal For the cyclic shift value, It can be defined and used as follows, and at this time can be set as upper layer signaling. At this time, is the number of SRS antenna ports (= 3), And, for example, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 can be 0, 2, and 5, respectively. Hereinafter, in calculating the cyclic shift interval between antenna ports, when the value of the cyclic shift reaches the maximum value, the property that the value of the cyclic shift returns to 0 again can be utilized. More specifically, when the maximum value of the cyclic shift is 8, the value of the cyclic shift can be 0, 1, 2, 3, 4, 5, 6, 7, and then returns to 0 again. In this case, the cyclic shift interval between antenna ports 1000 and 1001 can be 2 (2 - 0 = 2), the cyclic shift interval between 1001 and 1002 can be 3 (5 - 2 = 3), and the cyclic shift interval between 1002 and 1000 can be 5 (8 - 5) = 3) (i.e., when calculating the cyclic shift interval between ports 1002 and 1000, the cyclic shift value of port 1000, which has a cyclic shift value of 0, is assumed to be 8), so that unequal cyclic shift intervals can occur, resulting in different channel estimation performances between antenna ports. Alternatively, the terminal For the cyclic shift value, It can be defined and used as follows, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 can be 0, 3, and 6, respectively. Hereinafter, in calculating the cyclic shift interval between antenna ports, when the value of the cyclic shift reaches the maximum value, the property that the value of the cyclic shift returns to 0 again can be utilized. More specifically, when the maximum value of the cyclic shift is 8, the value of the cyclic shift can be 0, 1, 2, 3, 4, 5, 6, 7, and then returns to 0 again. Similarly, in this case, the cyclic shift interval between antenna ports 1000 and 1001 can be 3, the cyclic shift interval between 1001 and 1002 can be 3, and the cyclic shift interval between 1002 and 1000 can be 2 (8 - 6 = 2) (i.e., when calculating the cyclic shift interval between ports 1002 and 1000, the cyclic shift value of port 1000, which has a cyclic shift value of 0, is assumed to be 8), which can result in unequal cyclic shift intervals and thus different channel estimation performance between antenna ports.

[0253] According to one embodiment of the present disclosure, the terminal If, can be defined as, If, can be defined as follows. That is, the terminal transmits antenna ports 1000 and 1002 at the same RE location with different cyclic shift values, and transmits antenna port 1001 at a different RE location, so that although frequency resources are doubled, the cyclic shift interval between the two antenna ports allocated within the same RE can be maximized. The terminal For the cyclic shift value, It can be defined and used as follows. For example, In this case, the cyclic shift values ​​for antenna ports 1000 and 1002 at comb offset 0 may be 0 and 4, respectively, and the cyclic shift value for antenna port 1001 at comb offset 1 may be 0. In this case, the cyclic shift interval between antenna ports 1000 and 1002 is 4, and antenna port 1001 is not assigned a different cyclic shift value if there is no other SRS transmission assignment from the base station, so the channel estimation performance between antenna ports may be different. In addition, even if transmission is performed at different comb offset positions, since the interval between comb offsets differs by only 1, as in the above-described method, the cyclic shift value for antenna port 1000 at comb offset 0 and the cyclic shift value for antenna port 1001 at comb offset 1 are the same as 0, which may be a factor that makes it difficult to distinguish between antenna ports during channel estimation. Therefore, the terminal The cyclic shift value of If you define and use it like this, In this case, the cyclic shift values ​​for antenna ports 1000 and 1002 at comb offset 0 may be 0 and 4, respectively, and the cyclic shift value for antenna port 1001 at comb offset 1 may be 8. Therefore, even if the comb offsets differ by 1, the cyclic shift values ​​at each comb offset are allocated without overlapping each other, so that a clear distinction can be made between antenna ports during channel estimation.

[0254] The terminal is a comb size of 4 (e.g., That is, according to the above [Table 15] ), the comb offset values ​​of antenna ports 1000, 1001, and 1002 can be determined using at least one combination of the embodiments below.

[0255] According to one embodiment of the present disclosure, the terminal If, can be defined as and at this time can be set by upper layer signaling. That is, the terminal can transmit by distinguishing three antenna ports 1000, 1001, and 1002 with different cyclic shift values ​​at the same RE location, so frequency resource allocation efficiency can be good. The terminal For the cyclic shift value, It can be defined and used as follows, and at this time can be set as upper layer signaling. For example, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 can be 0, 4, and 8, respectively. Hereinafter, in calculating the cyclic shift interval between antenna ports, if the value of the cyclic shift reaches the maximum value, the property that the value of the cyclic shift returns to 0 again can be utilized. More specifically, if the maximum value of the cyclic shift is 12, the values ​​of the cyclic shift can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and then return to 0 again. In this case, since the intervals between two of the three antenna ports can both be 4 (i.e., when calculating the cyclic shift interval between ports 1002 and 1000, the cyclic shift value of port 1000, which has a cyclic shift value of 0, is assumed to be 12), the channel estimation performance between antenna ports can be similar.

[0256] According to one embodiment of the present disclosure, the terminal If, can be defined as, If, can be defined as follows. That is, the terminal transmits antenna ports 1000 and 1002 at the same RE location with different cyclic shift values, and transmits antenna port 1001 at a different RE location, so that although the frequency resources are used twice, the cyclic shift interval between the two antenna ports allocated within the same RE can be maximized. The terminal For the cyclic shift value, It can be defined and used as follows. For example, In this case, the cyclic shift values ​​for antenna ports 1000 and 1002 at comb offset 0 may be 0 and 6, respectively, and the cyclic shift value for antenna port 1001 at comb offset 2 may be 0. In this case, the cyclic shift interval between antenna ports 1000 and 1002 is 6, and antenna port 1001 is not assigned a different cyclic shift value if there is no other SRS transmission assignment from the base station, so the channel estimation performance between antenna ports may be different.

[0257] According to one embodiment of the present disclosure, the terminal If, can be defined as follows. That is, the terminal uses RE resources by transmitting at different comb offset positions for each antenna port, but since there are no other antenna ports allocated within the same RE, the base station can appropriately perform cyclic shift allocation for other SRS transmissions so that the cyclic shift interval can be maximized. The terminal For the cyclic shift value, It can be defined and used as follows. For example, In this case, the cyclic shift values ​​for each antenna port 1000, 1001, and 1002 at comb offsets 0, 1, and 2 may all be 0. In this case, since antenna ports 1000, 1001, and 1002 are not assigned different cyclic shift values ​​if there is no other SRS transmission assignment from the base station, if the base station performs different SRS transmission assignments equally for each RE, the channel estimation performance between antenna ports may be similar. In addition, even if SRSs are transmitted at different comb offset positions, since the interval between comb offsets differs by only one, if the cyclic shift values ​​for each antenna port 1000, 1001, and 1002 at comb offsets 0, 1, and 2 are all the same as 0, as in the above-described method, it may be difficult to distinguish between antenna ports during channel estimation. Therefore, the terminal The cyclic shift value of If we define and use them together, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 at comb offsets 0, 1, and 2 can be 0, 4, and 8, respectively, so that even if the comb offsets differ by 1, the cyclic shift values ​​at each comb offset are allocated without overlapping each other, thereby enabling clear distinction between antenna ports during channel estimation.

[0258] According to one embodiment of the present disclosure, the terminal has a comb size of 8 (e.g., That is, according to the above [Table 15] ), the comb offset values ​​of antenna ports 1000, 1001, and 1002 can be determined using at least one combination of the embodiments below.

[0259] According to one embodiment of the present disclosure, the terminal If, can be defined as and at this time can be set by upper layer signaling. That is, the terminal can transmit by distinguishing three antenna ports 1000, 1001, and 1002 with different cyclic shift values ​​at the same RE location, so that excellent frequency resource allocation efficiency can be guaranteed. The terminal For the cyclic shift value, It can be defined and used as follows, and at this time can be set as upper layer signaling. For example, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 can be 0, 2, and 4, respectively. In this case, since the spacing between two of the three antenna ports can all be the same as 2, the channel estimation performance between the antenna ports can be similar.

[0260] According to one embodiment of the present disclosure, the terminal If, can be defined as, If, can be defined as follows. That is, the terminal transmits antenna ports 1000 and 1002 at the same RE location with different cyclic shift values, and transmits antenna port 1001 at a different RE location, so that although the frequency resources are used twice, the cyclic shift interval between the two antenna ports allocated within the same RE can be maximized. The terminal For the cyclic shift value, It can be defined and used as follows. For example, In this case, the cyclic shift values ​​for antenna ports 1000 and 1002 at comb offset 0 may be 0 and 3, respectively, and the cyclic shift value for antenna port 1001 at comb offset 4 may be 0. In this case, the cyclic shift interval between antenna ports 1000 and 1002 is 3, and antenna port 1001 is not assigned a different cyclic shift value if there is no other SRS transmission assignment from the base station, so the channel estimation performance between antenna ports may be different.

[0261] According to one embodiment of the present disclosure, the terminal If, can be defined as follows. That is, the terminal transmits at different comb offset locations for each antenna port, so that RE resources are used three times, but since there are no other antenna ports allocated within the same RE, the base station can appropriately perform cyclic shift allocation for other SRS transmissions, so that the cyclic shift interval can be maximized. The terminal For the cyclic shift value, They can be defined and used together. For example, In this case, the cyclic shift values ​​for each antenna port 1000, 1001, and 1002 at comb offsets 0, 2, and 4 may all be 0. In this case, since antenna ports 1000, 1001, and 1002 are not assigned different cyclic shift values ​​if there is no other SRS transmission assignment from the base station, the channel estimation performance between antenna ports may be similar if the base station equally performs different SRS transmission assignments for each RE. In addition, even if they are transmitted at different comb offset positions, since the interval between comb offsets is only two, if the cyclic shift values ​​for each antenna port 1000, 1001, and 1002 at comb offsets 0, 1, and 2 are all the same as 0, it may be difficult to distinguish between antenna ports during channel estimation. Therefore, the terminal The cyclic shift value of If you define and use it like this, In this case, the cyclic shift values ​​for antenna ports 1000, 1001, and 1002 at comb offsets 0, 1, and 2 can be 0, 2, and 4, respectively, so that even if the comb offsets differ by 2, the cyclic shift values ​​at each comb offset are allocated without overlapping each other, thereby enabling clear distinction between antenna ports during channel estimation.

[0262] [Method 1-4]

[0263] According to one embodiment of the present disclosure, a terminal may define an SRS resource composed of three antenna ports to perform uplink channel estimation for three antenna ports in order to perform codebook-based PUSCH transmission through three antenna ports. That is, an SRS resource composed of three antenna ports may be defined / configured, an SRS may be transmitted to a base station through the three antenna ports on one SRS resource composed of three antenna ports, and the base station may perform uplink channel estimation using the SRS transmitted through the three antenna ports on the one SRS resource. In this case, the three antenna ports that may be included in the corresponding SRS resource may be 1000, 1001, and 1002, respectively. The terminal may expect that up to two SRS resources composed of three antenna ports are configured within an SRS resource set in which usage is set to codebook.

[0264] The terminal can be configured with multiple comb offsets and cyclic shift values ​​for each of three antenna ports. If the terminal is configured with two comb offsets and two cyclic shift values, the terminal can apply the comb offset and cyclic shift value to one of the three antenna ports (e.g., antenna port 1001) by using a method of allocating the comb offset and cyclic shift for each antenna port in an SRS resource that can be configured with one antenna port using the first comb offset and the first cyclic shift value, and can apply the second comb offset and the second cyclic shift value to two of the three antenna ports (e.g., antenna ports 1000 and 1002) by using a method of allocating the comb offset and cyclic shift for each antenna port in an SRS resource that can be configured with two antenna ports using the second comb offset and the second cyclic shift value.

[0265] If the terminal is set with three comb offsets and three cyclic shift values, the terminal may apply one comb offset and the first cyclic shift value to one antenna port (e.g., antenna port 1000) among three antenna ports by using a method of allocating a comb offset and a cyclic shift for each antenna port in an SRS resource that may be configured with one antenna port by using the first comb offset and the first cyclic shift value, and may apply the second comb offset and the second cyclic shift value to one antenna port (e.g., antenna port 1001) among three antenna ports by using a method of allocating a comb offset and a cyclic shift for each antenna port in an SRS resource that may be configured with one antenna port by using the second comb offset and the second cyclic shift value, and may apply the third comb offset and the third cyclic shift value to one antenna port (e.g., antenna port 1002) among three antenna ports by using a method of allocating a comb offset and a cyclic shift for each antenna port in an SRS resource that may be configured with one antenna port. 1002) can be applied to the third comb offset and third cyclic shift values.

[0266] The terminal may be notified by the base station of at least one combination of [Method 1-1] to [Method 1-4] through at least one combination of upper layer signaling, MAC-CE signaling, and L1 signaling, or may expect that at least one combination of [Method 1-1] to [Method 1-4] is fixedly defined in the standard. Additionally, if the terminal is notified by the base station of at least one combination of specific methods through at least one combination of upper layer signaling, MAC-CE signaling, and L1 signaling, it may mean that the terminal cannot support one or more other combinations of methods. For example, the terminal may expect that [Method 1-1] is fixedly defined in the standard, and the terminal may assume that [Method 1-1] is used to configure SRS resources during codebook-based PUSCH transmission through three antenna ports. As another example, the terminal may be notified from the base station about the above [Method 1-4] through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling, and in this case, the terminal may consider that it has been notified by the base station that the above [Method 1-1] is not supported.

[0267] The terminal may report to the base station, based on the terminal capability, whether it can support at least one combination of [Method 1-1] to [Method 1-4]. In this case, if the terminal reports to the base station, based on the terminal capability, that a combination of one or more specific methods can be supported, it may be regarded that the terminal has reported that it cannot support one or more other combinations of methods. For example, the terminal may report to the base station whether it can support [Method 1-1]. As another example, the terminal may report to the base station that it can support [Method 1-4], and such terminal capability report may mean that the terminal cannot support [Method 1-1].

[0268] <Second Embodiment: Method for Defining an Uplink Codebook for a Terminal Supporting Three Transmit Antennas>

[0269] A method for defining an uplink codebook for a terminal supporting three transmit antennas according to one embodiment of the present disclosure is described. This embodiment may operate in combination with at least one other embodiment described in the present disclosure.

[0270] A terminal supporting three transmit antennas can report to the base station that it is capable of codebook-based PUSCH transmission using three antenna ports based on its terminal capability. In this case, the terminal can report to the base station that only non-coherent transmission is possible. For this codebook-based PUSCH transmission method, the terminal can receive TPMI corresponding to the three antenna ports from the base station. If the terminal supports three transmit antennas, it can support a non-coherent codebook. In this case, the non-coherent precoding matrix W for 1-layer, 2-layer, and 3-layer transmission using three antenna ports in the terminal can be defined as shown in [Table 23], [Table 24], and [Table 25], respectively.

[0271] In [Table 24] below, the terminal can also receive from the base station a matrix in which the order of the two columns of TPMI 0, 1, and 2 are swapped. For example, the terminal can receive from the base station a matrix in which the two columns of TPMI 0 are swapped in [Table 24] below. A matrix such as the following can also be instructed from the base station. In addition to the matrix with the two columns of TPMI 0 reversed, if we include the matrix with the two columns of TPMI 1 reversed and the matrix with the two columns of TPMI 2 reversed, Table 24 below can include six matrices to which TPMI 0 to 5 are assigned.

[0272] Similarly, in Table 25 below, the terminal can also support matrices in which the order of the three columns of TPMI 0 is swapped. For example, the terminal can support matrices in which the positions of the three columns of TPMI 0 are swapped in Table 25 below. A matrix such as this can also be instructed from the base station. At this time, since the number of cases in which different orders of three different columns can be arranged is a total of 6 (3! = 3*2*1 = 6), Table 25, which is a codebook for 3-port 3-layer transmission, can include 6 matrices to which TPMI 0 to 5 are assigned.

[0273] [Table 23]

[0274]

[0275] [Table 24]

[0276]

[0277] [Table 25]

[0278]

[0279] <Third embodiment: SRS support method for non-codebook use for a terminal supporting three transmission antennas>

[0280] As one embodiment of the present disclosure, a method for supporting SRS for non-codebook purposes for a terminal supporting three transmit antennas is described. This embodiment may operate in combination with at least one other embodiment described in the present disclosure.

[0281] According to one embodiment of the present disclosure, a terminal supporting three transmit antennas may be configured with noncodebook for txConfig, which is an upper layer signaling, for noncodebook-based PUSCH transmission as described above. In addition, a terminal supporting three transmit antennas may be configured with an SRS resource set, in which usage, which is an upper layer signaling, is set with noncodebook, from a base station, and the terminal may be configured with up to three SRS resources within the configured SRS resource set. In this case, each SRS resource within the SRS resource set may be configured with (or may include) one antenna port.

[0282] According to one embodiment of the present disclosure, the terminal can receive an SRI field from a base station, and the received SRI field It can be composed of bits, can mean the number of SRS resources set within the SRS resource set, and can be up to three as described above.

[0283] If maxMIMO-Layers in PUSCH-ServingCellConfig, which is the upper layer signaling, is set to the terminal, can follow the value set to maxMIMO-Layers, otherwise, the above The maximum number of layers that can be applied when the PUSCH operation is for non-codebook purposes reported by the terminal may follow the value.

[0284] The terminal may report the maximum number of layers for uplink transmission for at least one combination of 3, 5, 6, 7, and 8 in addition to 1, 2, and 4. In this case, the terminal may report the maximum number of layers that can be supported individually for codebook-based PUSCH transmission and non-codebook-based PUSCH transmission. That is, information about the maximum number of layers that can be supported for codebook-based PUSCH transmission and information about the maximum number of layers that can be supported for non-codebook-based PUSCH transmission may be reported separately.

[0285] According to one embodiment of the present disclosure, when the reportQuantity in the CSI-ReportConfig, which is an upper layer signaling, is set to one of cri-RSRP-Index, ssb-Index-RSRP-Index, cri-SINR-Index, and ssb-Index-SINR-Index, the terminal may additionally report capabilityIndex to the L1-RSRP or L1-SINR report, and the capabilityIndex may indicate the maximum number of SRS antenna ports supported by the terminal, and the value of capabilityIndex may be associated with a specific panel of the terminal (i.e., an association relationship may be configured). Through the association / association relationship between the value of capabilityIndex reported together with the L1-RSRP or L1-SINR report and the specific panel of the terminal, the base station may assume that the L1-RSRP or L1-SINR value reported by the terminal is measured based on a reference signal received from which panel of the terminal. For example, when a specific panel of a terminal supports up to two SRS antenna ports and the terminal reports L1-RSRP received through the panel supporting up to two SRS antenna ports, if the terminal has reportQuantity set to cri-RSRP-Index as described above, the terminal may report 2 as the capabilityIndex value.

[0286] According to one embodiment of the present disclosure, a terminal may report terminal capabilities for UE capability value reporting to a base station. Here, the terminal capability report for UE capability value reporting may be a report on candidate values ​​that can be used as a value of capabilityIndex, which indicates the maximum number of SRS antenna ports supported by the terminal. That is, when {X, Y} is reported according to UE capability value reporting, when the terminal reports capabilityIndex, the capabilityIndex may be reported as one of X or Y. In this case, the terminal may report up to four values ​​to the base station as terminal capability reports for UE capability value reporting, and each reported value may be selected as a different value from {1, 2, 4}. For example, the terminal may report three values ​​to the base station, and the reported values ​​may be 1, 2, and 4, respectively. As another example, a terminal may report two values ​​to a base station, and the reported values ​​may be 2 and 4 (or {1 and 2}, or {1 and 4}), respectively. In addition, terminal capability reporting for UE capability value reporting may be reported per frequency band. In particular, although a terminal may report up to four values ​​to a base station as terminal capability reporting for UE capability value reporting, if each reported value can be selected as a different value among {1, 2, 4}, in reality, up to three different values ​​can be reported, and thus, the terminal capability of reporting up to four values ​​may not be utilized to its fullest extent.

[0287] According to one embodiment of the present disclosure, if a terminal supporting three transmit antennas reports the terminal capability for UE capability value reporting to a base station, the terminal may use a combination of at least one of the embodiments described below.

[0288] [Method 3-1]

[0289] According to one embodiment of the present disclosure, when a terminal supporting three transmit antennas reports terminal capabilities for UE capability value reporting to a base station, the terminal may report up to four values ​​to the base station, and each reported value may be selected as a different value from {1, 2, 3}. For example, the terminal may report three values ​​of 1, 2, and 3 to the base station, and the base station, which has received three values ​​including 1, 2, and 3 from the terminal, may expect that the terminal will report one of the three values ​​using two bits when reporting capabilityIndex. For example, the two-bit codepoint '00' corresponds to 1, the codepoint '01' corresponds to 2, the codepoint '10' corresponds to 3, and the codepoint '11' may be reserved. At this time, the value 3 reported by the terminal may mean that the maximum number of SRS ports of the terminal is 3, and when 3 is reported as the maximum number of SRS ports, a terminal supporting 3 transmission antennas may use a method of not transmitting 1 of the antenna ports of an SRS resource configured with 4 antenna ports as in [Method 1-1] for SRS transmission, or may use an SRS resource configured with 1 antenna port and an SRS resource configured with 2 antenna ports together as in [Method 1-2], or may use an SRS resource configured with 3 antenna ports as in [Method 1-3] and [Method 1-4], or may use a method by combining at least one of the [Methods 1-1] to [Methods 1-4].

[0290] [Method 3-2]

[0291] According to one embodiment of the present disclosure, when a terminal supporting three transmit antennas reports terminal capabilities for UE capability value reporting to a base station, the terminal may report up to four values ​​to the base station, and each reported value may be selected as a different value from {1, 2, 4}. For example, the terminal may report three values ​​of 1, 2, and 4 to the base station, and the base station may expect that the terminal reports one of the three values ​​using two bits when reporting capabilityIndex. For example, the two-bit codepoint '00' corresponds to 1, codepoint '01' corresponds to 2, codepoint '10' corresponds to 4, and codepoint '11' may be reserved. In this case, the value 4 reported by the terminal may mean that the maximum number of SRS ports is 3. That is, even if the terminal reports 4, the base station can regard the reported value of 4 as 3 for a terminal that supports three transmit antennas. This interpretation can be applied particularly when a terminal that supports three transmit antennas uses a method of not transmitting on one of the antenna ports of an SRS resource consisting of four antenna ports, as in [Method 1-1] above.

[0292] Additionally, a terminal supporting four transmit antennas can report up to four values ​​to the base station when reporting the terminal capability for UE capability value reporting to the base station, and each reported value can be selected from different values ​​among {1, 2, 3, 4}. For example, the terminal can report four values ​​of 1, 2, 3, and 4 to the base station, and the base station can expect that the terminal reports one of the four values ​​using two bits when reporting capabilityIndex. For example, the two-bit codepoint '00' can correspond to 1, codepoint '01' can correspond to 2, codepoint '10' can correspond to 3, and codepoint '11' can correspond to 4. At this time, the meaning of the value 4 reported by the terminal may mean that the maximum number of SRS ports is 4, and the meaning of the value 3 reported by the terminal may mean that the maximum number of SRS ports is 3.

[0293] Additionally, a terminal supporting four transmit antennas can report up to four values ​​to the base station when reporting the terminal capability for UE capability value reporting to the base station, and each reported value is selected from different values ​​among {1, 2, 4}, and in the case of 4, it can be reported up to twice. For example, the terminal can report four values ​​of 1, 2, 4, 4 to the base station, and the base station can expect that the terminal reports one of the four values ​​using two bits when reporting capabilityIndex. For example, the two-bit codepoint '00' can correspond to 1, codepoint '01' can correspond to 2, codepoint '10' can correspond to 4, and codepoint '11' can also correspond to 4. At this time, if the terminal reports a code point mapped to report 4, among the code points mapped to 4, the meaning of the value 4 mapped to a code point with a smaller code point value (i.e., '10') may mean that the maximum number of SRS ports is 3, and the meaning of the value 4 mapped to a code point with a larger code point value may mean that the maximum number of SRS ports is 4.

[0294] Additionally, a terminal supporting four transmit antennas can report up to four values ​​to the base station when reporting the terminal capability for UE capability value reporting to the base station, and each reported value can be selected from different values ​​among {1, 2, 4}. For example, the terminal can report three values ​​of 1, 2, and 4 to the base station, and the base station can expect that the terminal reports one of the three values ​​using two bits when reporting capabilityIndex. For example, the two-bit codepoint '00' can correspond to 1, codepoint '01' can correspond to 2, codepoint '10' can correspond to 4, and codepoint '11' can also correspond to 4. In this case, the value 4 reported by the terminal can mean that the maximum number of SRS ports is 4. That is, a terminal that supports four transmit antennas may not support the value 3 when reporting terminal capabilities for UE capability value reporting, and not supporting the value 3 when reporting terminal capabilities for UE capability value reporting may mean that the terminal does not perform SRS transmission represented by three antenna ports.

[0295] According to one embodiment of the present disclosure, when a terminal has up to eight transmit antennas, in addition to the above-described 1, 2, 3, and 4, at least one combination of 5, 6, 7, and 8 can also be reported when reporting UE capability values, and if the number of candidate values ​​exceeds four, the capabilityindex value reported by the terminal can be expressed with 3 bits.

[0296] According to one embodiment of the present disclosure, a terminal may report to a base station a reduced number of MIMO layers preferred by the terminal to solve a heat generation problem or reduce power consumption of the terminal through reducedMIMO-LayersFR1-DL, reducedMIMO-LayersFR1-UL, reducedMIMO-LayersFR2-DL, reducedMIMO-LayersFR2-UL, reducedMIMO-LayersFR2-2-DL, or reducedMIMO-LayersFR2-2-UL in UEAssistanceInformation, which is an upper layer signaling that the terminal may transmit. If the terminal has three transmit antennas, the terminal may report to the base station one natural number value from 1 to 3 for reducedMIMO-LayersFR1-UL, reducedMIMO-LayersFR2-UL, or reducedMIMO-LayersFR2-2-UL. The base station may not expect that the terminal reports a value of 4 to the base station through reducedMIMO-LayersFR1-UL, reducedMIMO-LayersFR2-UL, or reducedMIMO-LayersFR2-2-UL when the terminal has three transmit antennas. If the terminal has eight transmit antennas, the terminal may report a natural number value between 1 and 8 to the base station for reducedMIMO-LayersFR1-UL, reducedMIMO-LayersFR2-UL, or reducedMIMO-LayersFR2-2-UL.

[0297] According to one embodiment of the present disclosure, the terminal may be notified by the base station of at least one combination of [Method 3-1] and [Method 3-2] through at least one combination of upper layer signaling, MAC-CE signaling, and L1 signaling, or may expect that at least one combination of [Method 3-1] and [Method 3-2] is fixedly defined in the standard. Additionally, if the terminal is notified by the base station of at least one combination of specific methods through at least one combination of upper layer signaling, MAC-CE signaling, and L1 signaling, it may mean that the terminal cannot support specific one or more other combinations of methods. For example, the terminal may expect that [Method 3-1] is fixedly defined in the standard, and the terminal may assume that [Method 3-1] is used for UE capability value reporting. As another example, the terminal may be notified from the base station about the above [Method 3-2] through a combination of at least one of upper layer signaling, MAC-CE signaling, and L1 signaling, and in this case, the terminal may consider that it has been notified by the base station that the above [Method 3-1] is not supported.

[0298] According to one embodiment of the present disclosure, a terminal may report to a base station, based on terminal capabilities, whether it can support at least one combination of [Method 3-1] and [Method 3-2]. In this case, if the terminal reports to the base station, based on terminal capabilities, that a combination of one or more specific methods can be supported, it may be regarded that the terminal has reported that it cannot support one or more other combinations of methods. For example, the terminal may report to the base station whether it can support [Method 3-1]. As another example, the terminal may report to the base station that it can support [Method 3-2], and such terminal capability report may mean that the terminal cannot support [Method 3-1].

[0299] <Fourth Embodiment: Phase Tracking Reference Signal Transmission Method for a Terminal Supporting Three Transmission Antennas>

[0300] Hereinafter, methods for transmitting a phase tracking reference signal (PTRS) by a terminal capable of transmitting an uplink signal with three transmission antennas according to an embodiment of the present disclosure are specifically described.

[0301] When a UE transmits an uplink signal via three transmit antennas, and before defining a DCI field to indicate a DMRS associated with the PTRS transmitted together in the uplink signal transmitted by the UE, a rule for the DMRS port with which each PTRS port can be associated is first defined. An uplink signal transmitted via three transmit antennas can be transmitted with one or two PTRS ports. If codebook-based PUSCH transmission is supported, each PTRS port can define a rule in advance to associate which PTRS port can be associated with which layer transmitted via a specific PUSCH antenna port, or a PTRS port can be associated with any layer without a separate rule. For example, if only one PTRS port is configured (for example, maxNrofPorts in PTRS-UplinkConfig is set to 'n1'), a PTRS port can be associated with any one of the layers, and there is no need to consider the condition for which layer is transmitted via a specific PUSCH antenna port. If the number of layers of a scheduled (or schedulable) PUSCH is greater than 1, the UE can transmit PTRS by associating a PTRS port with a DMRS port (layer) indicated by a specific DCI field included in the DCI (e.g., PTRS-DMRS association field, PTRS-DMRS association field). If two PTRS ports are configured to be available (for example, maxNrofPorts in PTRS-UplinkConfig is set to 'n2'), the DMRS port that can be associated with the PTRS port of the PUSCH transmitted based on the codebook can be determined in the following manner.

[0302] [Method 1] A layer (DMRS port) transmitted to a specific PUSCH antenna port may be associated with an uplink PTRS port. For example, PTRS port 0 may be associated with a layer (or DMRS port) transmitted to PUSCH antenna port 1000 and / or PUSCH antenna port 1002, and PTRS port 1 may be associated with a layer (or DMRS port) transmitted to PUSCH antenna port 1001 and / or PUSCH antenna port 1003. If a terminal supporting three transmit antennas does not support PUSCH antenna port 1003 (or any one of PUSCH antenna port 1000 to PUSCH antenna port 1003), PTRS port 1 may be associated with a layer (or DMRS port) transmitted to PUSCH antenna port 1001. The specific example to explain [Method 1] is only one example, and PTRS port 0 may be associated with a layer (or DMRS port) transmitted to PUSCH antenna port 1001, and PTRS port 1 may be associated with a layer (or DMRS port) transmitted to PUSCH antenna port 1000 and / or PUSCH antenna port 1002. Alternatively, PUSCH and PTRS may be transmitted by defining an association between PTRS ports and layers transmitted to other combinations of PUSCH antenna ports.

[0303] [Method 2] An uplink PTRS port may be associated with a layer (or DMRS port) transmitted through any PUSCH antenna port. [Method 2] allows a PTRS port to be associated with any layer (or DMRS port) without any restrictions, and the UE may determine a DMRS port associated with a PTRS port transmitted together with a scheduled PUSCH according to a PTRS-DMRS association field indicated by a scheduling DCI. Or, in the case of a configured grant PUSCH, the PTRS-DMRS association relationship indicated according to a set rule may be determined (for example, if a configured grant type 1 PUSCH is scheduled, the UE determines a DMRS port associated with the transmitting PTRS port by considering the PTRS-DMRS association field as '0' or '00').

[0304] The terminal can determine the DMRS port associated with the PTRS port transmitted together with the scheduled codebook-based PUSCH based on either [Method 1] or [Method 2]. In the following embodiments, for convenience of explanation, it is assumed that the DMRS port associated with the PTRS port transmitted together with the codebook-based PUSCH is determined according to [Method 1].

[0305] If a terminal supporting three transmit antennas supports non-codebook-based PUSCH transmission, ptrs-PortIndex can be set to n0 or n1 in the upper layer configuration of an SRS resource in an SRS resource set with usage of 'nonCodebook'. If only one uplink PTRS port is supported, the upper layer parameter ptrs-PortIndex can be set to n0 (or n1). If two uplink PTRS ports are supported, the upper layer parameter ptrs-PortIndex can be set to n0 or n1.

[0306] The following specifically describes how to determine which of up to three layers (or DMRS ports) is associated with a PTRS port, depending on the number of uplink PTRS ports supported, when a terminal supporting three transmit antennas supports one or two uplink PTRS ports.

[0307] If a terminal supporting three transmit antennas supports two uplink PTRS ports, the number of bits required for each PUSCH layer to determine the layer (or DMRS port) associated with the PTRS port is as follows.

[0308] If the number of layers of the scheduled codebook-based PUSCH is 1: The terminal transmits a PTRS port associated with one PUSCH layer in association with the corresponding layer. For example, if one PUSCH layer is transmitted through PUSCH antenna port 1000 and / or PUSCH antenna port 1002, PTRS port 0 may be transmitted in association with the corresponding PUSCH layer (or DMRS port for the corresponding PUSCH transmission). At this time, the index of the subcarrier on which the PTRS port is transmitted within the RB (resource block) is determined based on the port index of the DMRS port indicated for the corresponding PUSCH layer and the RRC parameter (e.g., resourceElementOffset) set in the upper layer. is determined. If one PUSCH layer is transmitted to PUSCH antenna port 1001, PTRS port 1 can be transmitted in association with the corresponding PUSCH layer (or DMRS port for the corresponding PUSCH transmission). At this time, the index of the subcarrier on which the PTRS port is transmitted within the RB (resource block) is determined according to the port index of the DMRS port indicated for the corresponding PUSCH layer and the RRC parameter (e.g., resourceElementOffset) set in the upper layer. is decided.

[0309] If the number of layers of the scheduled non-codebook-based PUSCH is 1: The UE transmits a PTRS port associated with one PUSCH layer in association with the corresponding layer. For example, if one PUSCH layer is transmitted based on an SRS resource in which the upper layer parameter ptrs-PortIndex is set to n0 (i.e., if the PUSCH is scheduled by indicating the corresponding SRS resource with the SRI field in the DCI or the upper layer parameter srs-ResourceIndicator), PTRS port 0 may be transmitted in association with the corresponding PUSCH layer (or the DMRS port for the corresponding PUSCH transmission). In this case, the index of the subcarrier on which the PTRS port is transmitted within the RB (resource block) is determined based on the port index of the DMRS port indicated for the corresponding PUSCH layer and the RRC parameter (e.g., resourceElementOffset) set in the upper layer. is determined. If one PUSCH layer is transmitted based on an SRS resource with the upper layer parameter ptrs-PortIndex set to n1 (i.e., the PUSCH is scheduled by indicating the corresponding SRS resource with the SRI field in the DCI or the upper layer parameter srs-ResourceIndicator), PTRS port 1 may be transmitted in association with the corresponding PUSCH layer (or the DMRS port for the corresponding PUSCH transmission). At this time, the index of the subcarrier on which the PTRS port is transmitted within the RB (resource block) is determined according to the port index of the DMRS port indicated for the corresponding PUSCH layer and the RRC parameter (e.g., resourceElementOffset) set in the upper layer. is decided.

[0310] If the number of layers of the scheduled codebook-based PUSCH is 2: The UE determines the PTRS ports associated with the two layers based on the actual number of PTRS ports according to the TPMI (or precoder configured with the higher layer parameter precodingAndNumberOfLayers) to be applied to the scheduled PUSCH, and transmits either one PTRS port associated with one of the two layers (if the actual number of PTRS ports is 1) or two PTRS ports associated with each layer (if the actual number of PTRS ports is 2). As a concrete example, if the precoder instructs to transmit the PUSCH of both layers through PUSCH antenna port 1000 or PUSCH antenna port 1002, the UE determines the actual number of PTRS ports to be 1 and transmits only PTRS port 0 together with the scheduled PUSCH. At this time, the MSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH may be referenced to determine the layer (or DMRS port) associated with PTRS port 0 among the two scheduled layers, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the UE may ignore the LSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH. As another specific example, if the precoder instructs to transmit the PUSCH of all two layers through PUSCH antenna port 1003, the UE determines the actual number of PTRS ports as 1 and transmits only PTRS port 1 together with the scheduled PUSCH.At this time, to determine the layer (or DMRS port) associated with PTRS port 1 among the two scheduled layers, the LSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH may be referred to, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the UE may ignore the MSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH. As another concrete example, if the precoder instructs to transmit one layer to PUSCH antenna port 1000 and / or PUSCH antenna port 1002 and to transmit another layer to PUSCH antenna port 1001, the UE determines the actual number of PTRS ports to be 2 and transmits PTRS port 0 in association with the layer (or DMRS port) transmitting to PUSCH antenna port 1000 and / or PUSCH antenna port 1002 and transmits PTRS port 1 in association with the layer (or DMRS port) transmitting to PUSCH antenna port 1001. In this case, the UE may ignore both bits of the PTRS-DMRS association field included in the DCI scheduling the PUSCH or the UE may expect that the base station sets the PTRS-DMRS association field to '00'.

[0311] If the number of layers of the scheduled non-codebook-based PUSCH is 2: The UE determines the PTRS ports associated with the two layers based on the actual number of PTRS ports according to the SRI (or the higher layer parameter srs-ResourceIndicator) to be applied to the scheduled PUSCH, and transmits one PTRS port associated with one of the two layers (if the actual number of PTRS ports is 1) or two PTRS ports associated with each layer (if the actual number of PTRS ports is 2). As a concrete example, if the SRI instructs to transmit the PUSCH of the two layers on two SRS resources, both of which have the higher layer parameter ptrs-PortIndex set to n0, the UE determines the actual number of PTRS ports to be 1 and transmits only PTRS port 0 along with the scheduled PUSCH. At this time, the MSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH may be referenced to determine the layer (or DMRS port) associated with PTRS port 0 among the two scheduled layers, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the UE may ignore the LSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH. As another specific example, if the SRI instructs to transmit the PUSCH of the two layers using two SRS resources in which the upper layer parameter ptrs-PortIndex is both set to n1, the UE determines the actual number of PTRS ports to be 1 and transmits only PTRS port 1 together with the scheduled PUSCH.At this time, to determine the layer (or DMRS port) associated with PTRS port 1 among the two scheduled layers, the LSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH may be referred to, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the UE may ignore the MSB 1 bit of the PTRS-DMRS association field included in the DCI that schedules the PUSCH. As another concrete example, if the SRI indicates one SRS resource with the upper layer parameter ptrs-PortIndex set to n0 and one SRS resource with the upper layer parameter ptrs-PortIndex set to n1, the UE determines the actual number of PTRS ports to be 2 and transmits PTRS port 0 in association with the layer transmitted according to the SRS resource with ptrs-PortIndex set to n0 and transmits PTRS port 1 in association with the layer transmitted according to the SRS resource with ptrs-PortIndex set to n1. In this case, the UE may ignore both bits of the PTRS-DMRS association field included in the DCI scheduling the PUSCH or the UE may expect that the base station sets the PTRS-DMRS association field to '00'.

[0312] If the number of layers of the scheduled codebook-based PUSCH is 3: The UE determines the number of actual PTRS ports as 2 based on the TPMI (or precoder configured by the higher layer parameter precodingAndNumberOfLayers) to be applied to the scheduled PUSCH, and determines that one PTRS port among the two PTRS ports can be associated with two layers, and the other PTRS port can be associated with one layer. In order to determine the layer (or DMRS port) associated with the PTRS port that can be associated with two layers, the UE may refer to the PTRS-DMRS association field included in the scheduling DCI, or in the case of a configured grant-based PUSCH, the UE may regard the PTRS-DMRS association field as '00'. As a specific example, if the precoder instructs to transmit two layers through PUSCH antenna port 1000 or PUSCH antenna port 1002 and one layer through PUSCH antenna port 1001, the UE may determine the actual number of PTRS ports to be 2, and transmit PTRS port 0 by associating it with one of the two layers transmitted through PUSCH antenna port 1000 or PUSCH antenna port 1002, and transmit PTRS port 1 by associating it with one layer transmitted through PUSCH antenna port 1001. At this time, in order to determine which of the two layers is associated with PTRS port 0 (or DMRS port), the MSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH may be referred to, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the terminal may ignore the LSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH.As another specific example, if the precoder instructs to transmit one layer through PUSCH antenna port 1000 or PUSCH antenna port 1002 and two layers through PUSCH antenna port 1001, the UE may determine the actual number of PTRS ports to be 2 and transmit PTRS port 0 by associating it with one layer transmitted through PUSCH antenna port 1000 or PUSCH antenna port 1002, and transmit PTRS port 1 by associating it with one of the two layers transmitted through PUSCH antenna port 1001. At this time, to determine which of the two layers is associated with PTRS port 1 (or DMRS port), the LSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH may be referred to, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the terminal may ignore the MSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH.

[0313] If the number of layers of the scheduled non-codebook based PUSCH is 3: The UE can determine the number of actual PTRS ports as 2 based on the SRI to be applied to the scheduled PUSCH, and determine that one of the two PTRS ports can be associated with two layers, and the other PTRS port can be associated with one layer. In addition, the UE can refer to the PTRS-DMRS association field included in the scheduling DCI to determine the layer (or DMRS port) associated with the PTRS port that can be associated with two layers, or in the case of a configured grant based PUSCH, the PTRS-DMRS association field can be regarded as '00'. As a concrete example, if the SRI instructs to transmit two layers with two SRS resources having the upper layer parameter ptrs-PortIndex set to n0 and to transmit one layer with one SRS resource having the upper layer parameter ptrs-PortIndex set to n1, the UE may determine the actual number of PTRS ports to be 2, and transmit PTRS port 0 by associating it with one of the two layers transmitted with the two SRS resources having the ptrs-PortIndex set to n0, and transmit PTRS port 1 by associating it with one layer transmitted with the one SRS resource having the ptrs-PortIndex set to n1. At this time, to determine which of the two layers is associated with PTRS port 0 (or DMRS port), the MSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH may be referred to, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the terminal may ignore the LSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH.As another concrete example, if the SRI instructs to transmit one layer with one SRS resource having the upper layer parameter ptrs-PortIndex set to n0 and to transmit two layers with two SRS resources having the upper layer parameter ptrs-PortIndex set to n1, the UE may determine the actual number of PTRS ports to be 2, and transmit PTRS port 0 with one layer transmitted with one SRS resource having ptrs-PortIndex set to n0, and transmit PTRS port 1 with one of the two layers transmitted with two SRS resources having ptrs-PortIndex set to n1. At this time, to determine which of the two layers is associated with PTRS port 1, the UE may refer to the LSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH, or in the case of a configured grant-based PUSCH, the PTRS-DMRS association field may be regarded as '00'. At this time, the terminal may ignore the MSB 1 bit of the PTRS-DMRS association field included in the DCI scheduling the PUSCH.

[0314] For the six cases described above, we can see that at most one DCI bit is required to determine the layer (or DMRS port) associated with the uplink PTRS. That is, if a terminal supporting three transmit antennas supports two uplink PTRS ports, we can see that the terminal can omit the remaining bits, except for one bit required to determine the DMRS port associated with the PTRS port.

[0315] If a PTRS-DMRS association field consisting of 1 bit can be used to indicate a DMRS port associated with PTRS even when a terminal supporting three transmit antennas supports one uplink PTRS port, the base station and the terminal can configure the PTRS-DMRS association field in the DCI with 1 bit for the case where three terminal transmit antennas are supported. That is, if an upper layer parameter for supporting three terminal transmit antennas is set, the bit size of the PTRS-DMRS association field in the DCI can be configured as 1. In order to utilize the PTRS-DMRS association field consisting of 1 bit as such, when a terminal supporting one uplink PTRS port supports the following, a method for determining one layer associated with the PTRS port among multiple layers (or DMRS ports) is specifically described.

[0316] If no separate additional method is considered for determining the DMRS associated with the PTRS, and one uplink PTRS port is supported for a terminal supporting three transmit antennas, the number of bits required for each PUSCH layer number to determine the layer (or DMRS port) associated with the PTRS port is as follows.

[0317] If the number of layers of the scheduled PUSCH is 1: The UE transmits one uplink PTRS port in association with one PUSCH layer (or DMRS port), regardless of whether the PTRS-DMRS association field indicates it. In this case, the UE may ignore the 2-bit PTRS-DMRS association field.

[0318] If the number of layers of the scheduled PUSCH is 2: The UE transmits by associating one PTRS port with one of the two layers by referring to the PTRS-DMRS association field. At this time, two of the four codepoints that can be indicated by the 2-bit PTRS-DMRS association field can be used to select one of the two layers. That is, the remaining two codepoints can be reserved, which can be interpreted as requiring only one bit of the 2-bit PTRS-DMRS association field.

[0319] If the number of layers of the scheduled PUSCH is 3: The UE refers to the PTRS-DMRS association field and transmits by associating one PTRS port with one of the three layers. At this time, three of the four codepoints that can be indicated by the 2-bit PTRS-DMRS association field can be used to select one of the three layers. That is, only the remaining one codepoint can be reserved, which can be interpreted as requiring all 2 bits of the PTRS-DMRS association field.

[0320] That is, as can be seen in the example described above, if no separate additional method is considered for determining the DMRS associated with the PTRS, a 2-bit indication field is required to select one layer to be associated with one uplink PTRS port considering all schedulable layers for a terminal supporting three transmit antennas. That is, unlike the case where only 1 bit is required to determine the DMRS port associated with a PTRS port when supporting two uplink PTRS ports for a terminal supporting three transmit antennas as discussed above, a terminal supporting one uplink PTRS port for a terminal supporting three transmit antennas may require 2 bits to determine the DMRS port associated with the PTRS port. If a terminal supporting three transmit antennas and supporting one uplink PTRS port can indicate the DMRS port associated with the PTRS port using only 1 bit or less, the number of bits in the PTRS-DMRS association field included in the DCI that schedules the PUSCH can be reduced from 2 bits to 1 bit. Alternatively, when configuring 2 bits for the PTRS-DMRS association field, 1 bit may be configured in the PTRS-DMRS association field and the remaining 1 bit may be configured using a reserved bit of another field in the DCI, for a total of 2 bits.

[0321] Based on the above characteristics, the following DCI fields can be considered as other fields that can contain reserved bits within the DCI to reduce the number of bits in the PTRS-DMRS association area:

[0322] The 'Antenna ports' field (meaning a field included in DCI format 0_1 ​​or DCI format 0_2) is a field for indicating the DMRS port of the scheduled PUSCH. The bit size of the antenna ports field can be determined by the type of DMRS (set by the upper layer parameter dmrs-Type), the symbol length of the DMRS (set by the upper layer parameter maxLength), and whether the enhanced DMRS type is set (set by the upper layer parameter enhanced-dmrs-Type). If the transform precoder is not set, a PUSCH with a rank of 1 to maxRank (when supporting codebook-based PUSCH transmission) or 1 to maxMIMO-Layer (when supporting non-codebook-based PUSCH transmission) can be scheduled according to the capability of the terminal, and the terminal can receive DMRS port information indicated by the antenna port field by referring to a table according to the rank (or layer) of the scheduled PUSCH and the above-described DMRS configuration (DMRS type, DMRS symbol length, etc.). At this time, since the number of bits in the Antenna port field is determined by considering the number of all layers on which the terminal can be scheduled, only some bits (or code points) may be used in the Antenna port field for indicating the DMRS port for the PUSCH scheduled to a specific layer, and the remaining bits (or code points) may be reserved. For example, if the transform precoder is not available (disabled), dmrs-Type is 1, enhanced-dmrs-Type is not set, and maxLength is set to 1, the number of bits in the Antenna ports field in the DCI format 0_1 ​​(or 0_2, for convenience of explanation, the description is based on DCI format 0_1, but the same can be applied to a PUSCH scheduled with DCI format 0_2) of the terminal may be determined to be 3.If the DCI format 0_1 ​​received by the terminal schedules a rank 1 (rank1 or layer 1) PUSCH, six code points in the 3-bit Antenna ports field can be used to indicate a DMRS port, and two code points can be reserved. Alternatively, if the DCI format 0_1 ​​received by the terminal schedules a rank 2 (rank2 or layer 2) PUSCH, four code points in the 3-bit Antenna ports field can be used to indicate a DMRS port, and four code points can be reserved. Alternatively, if the DCI format 0_1 ​​received by the terminal schedules a rank 3 (rank3 or layer 3) PUSCH, one code point in the 3-bit Antenna ports field can be used to indicate a DMRS port, and seven code points can be reserved. As can be seen from the examples of PUSCH scheduled with the three different ranks above, the number of reserved code points may vary depending on the rank number of the scheduled PUSCH for the Antenna ports field having the same number of bits.

[0323] In order to support one uplink PTRS port in a terminal that supports three transmit antennas as above, and to use the reserved bits or code points in the Antenna ports field to indicate the DMRS port associated with one uplink PTRS port, the following options can be used.

[0324] [Option 1] A new code point indicated by the PTRS-DMRS association field consisting of 1 bit and the Antenna ports field can be combined to determine the DMRS port associated with one PTRS port.

[0325] The DMRS port of the scheduled PUSCH can be indicated through the Antenna ports field, and additionally, the candidate layer to which the PTRS-DMRS association field is applied can be indicated. For example, the Antenna ports field for indicating the DMRS port of the PUSCH scheduled with a certain rank can be configured with multiple codepoints so that it can equally indicate a certain DMRS CDM group, a certain DMRS port, and a certain number of front-load symbols. If one of the multiple codepoints for indicating the same DMRS port is indicated through the Antenna ports field, the UE can identify some DMRS ports (e.g., one DMRS port out of three DMRS ports or two DMRS ports) among all DMRS ports as candidates for the DMRS port to which the PTRS port can be associated. Thereafter, the UE can determine one DMRS port among the identified some DMRS port candidates (e.g., two DMRS ports) by referring to the PTRS-DMRS association field consisting of a certain number of bits (e.g., 1 bit less than 2 bits) and associate it with the PTRS port.

[0326] For example, a table defining DMRS ports indicated through the Antenna ports field can be configured as follows. [Table 26] refers to a table for determining DMRS ports when the transform precoder is set to disable, dmrs-Type is set to 1, enhanced-dmrs-Type is not set, maxLength is set to 2, and the Antenna ports field consisting of 4 bits is indicated by DCI, and the rank of the PUSCH scheduled with the same DCI including the Antenna ports field is 3.

[0327] [Table 26]

[0328]

[0329] A DMRS CDM group without data can be defined as 2, and codepoints 0 and 3 can be used to indicate DMRS ports 0 to 2, and the number of front-load symbols can be 1. That is, if the Antenna ports field indicates codepoint 0 or codepoint 3, the UE can configure DMRS ports 0 to 2 of a PUSCH scheduled with a DCI including the corresponding Antenna ports field as a front-load DMRS of 1 symbol according to the two DMRS CDM groups. In this case, if the Antenna ports field indicates codepoint 0 and the UE transmits a codebook-based PUSCH and supports one uplink PTRS port, it can be understood that the UE transmits one uplink PTRS port in association with a DMRS port (or layer) transmitted to PUSCH antenna port 1000 and / or PUSCH antenna port 1002. If codebook-based PUSCH transmission is supported, PUSCH antenna port group 1 associated with PTRS in [Table 26] can be defined as a PUSCH antenna port group including PUSCH antenna port 1000 and / or PUSCH antenna port 1002. Alternatively, a separate PUSCH antenna port group may not be defined in the table, but may be implicitly determined by the base station and the UE according to some predefined rules. If two layers of a scheduled PUSCH are transmitted on PUSCH antenna port 1000 and / or PUSCH antenna port 1002, the UE can select one DMRS port by referring to the 1-bit PTRS-DMRS association field.If the Antenna ports field indicates codepoint 3 and the UE transmits a codebook-based PUSCH and supports one uplink PTRS port, it can be understood that the UE transmits one uplink PTRS port in association with a DMRS port (or layer) transmitted to PUSCH antenna port 1001. PUSCH antenna port group 2 associated with PTRS in [Table 26] can be defined as PUSCH antenna port 1001. Alternatively, a separate PUSCH antenna port group may not be defined in the table but may be implicitly determined according to some rule defined in advance by the base station and the UE. If the scheduled PUSCH is transmitted to PUSCH antenna port 1001, the UE may select one DMRS port by referring to or ignoring the 1-bit PTRS-DMRS association field.

[0330] If non-codebook based PUSCH transmission is supported, PUSCH antenna port group 1 associated with PTRS in [Table 26] can be defined as a layer (or DMRS port) transmitted according to an SRS resource in which a new parameter (e.g., PUSCHPortGroup or any parameter having the same function) in the upper layer parameter SRS-Resource is set to '1'. Alternatively, a separate PUSCH antenna port group can be implicitly determined according to some rule defined in advance by the base station and the terminal (e.g., a DMRS port transmitted according to the first N SRS resources among multiple SRS resources configured in an SRS resource set, etc.) without defining a separate PUSCH antenna port group as a new parameter (e.g., PUSCHPortGroup). Similarly, if non-codebook based PUSCH transmission is supported, PUSCH antenna port group 2 associated with PTRS in [Table 26] can be defined as a layer (or DMRS port) transmitted according to an SRS resource in which a new parameter (e.g., PUSCHPortGroup or any parameter with the same function) in the upper layer parameter SRS-Resource is set to '2'.Alternatively, a separate PUSCH antenna port group may be implicitly determined based on some rule predefined by the base station and the terminal (e.g., DMRS ports transmitted according to the last N or N+1 to M (where M is the number of all SRS resources in the SRS resource set whose usage is set to 'nonCodebook') SRS resources among multiple SRS resources set in the SRS resource set) without defining a new parameter (e.g., PUSCHPortGroup) for the separate PUSCH antenna port group.

[0331] [Table 26] is only one example for the above-described upper layer parameters, and similarly for other upper layer parameter settings, codepoints can be configured to indicate the same DMRS port but differently indicate the PUSCH antenna port group to which the PTRS is associated. In one embodiment, a new table for determining the DMRS port associated with the PTRS port can be defined by combining a PTRS-DMRS association field consisting of 1 bit and a new codepoint indicated by the Antenna ports field. For example, a new table can be defined according to the DMRS configuration and the number of PUSCH layers using the method of Option 1. The DMRS port associated with the PTRS port can be determined according to the defined table.

[0332] If there are not enough code points for this, only the code points for indicating some DMRS ports may be defined as multiple code points for indicating different PUSCH antenna port groups. Based on the example in [Table 26], only DMRS ports 0 to 2, where the number of DMRS CDM groups without data is 2 and the number of front-load symbols is 1, may be indicated by two different code points 0 and 3, and other DMRS ports (e.g., DMRS ports indicated by code points 1 and 2) may be indicated by only one code point.

[0333] [Option 2] The DMRS port associated with a PTRS port can be determined using only the Antenna ports field without the PTRS-DMRS association field. The DMRS port associated with a PTRS port can be determined only by referring to the code point indicated by the Antenna ports field.

[0334] The DMRS port of the scheduled PUSCH can be indicated through the Antenna ports field, and additionally, the DMRS port associated with the PTRS can be indicated together. For example, the Antenna ports field for indicating the DMRS port of the PUSCH scheduled for a certain rank can be configured with multiple codepoints so that it can identically indicate a certain DMRS CDM group, a certain DMRS port, and a certain number of front-load symbols. In addition, if one of the multiple codepoints for indicating the same DMRS port is indicated through the Antenna ports field, the UE can identify one DMRS port among all DMRS ports (e.g., one DMRS port among three DMRS ports) as a candidate DMRS port with which the PTRS port can be associated. Thereafter, the UE can associate one DMRS port with the PTRS port without receiving a separate PTRS-DMRS association field.

[0335] For example, a table defining DMRS ports indicated through the Antenna ports field can be configured as follows. [Table 27] refers to a table for determining DMRS ports when the transform precoder is set to disable, dmrs-Type is set to 2, enhanced-dmrs-Type is not set, maxLength is set to 2, and the Antenna ports field consisting of 5 bits is indicated by DCI, and the rank of the PUSCH scheduled with the same DCI including the Antenna ports field is 3.

[0336] [Table 27]

[0337]

[0338] DMRS CDM groups without data can be defined as 3, DMRS port 4, DMRS port 5, and DMRS port 10, and code points 5, 11, and 17 that can indicate the number of front-load symbols as 2. That is, if the Antenna ports field indicates code point 5, code point 11, or code point 17, the UE can configure DMRS ports of the PUSCH scheduled with the DCI including the corresponding Antenna ports field as front-load DMRS of 2 symbols according to the three DMRS CDM groups, DMRS port 4, DMRS port 5, and DMRS port 10. In this case, if the Antenna ports field indicates code point 5, the UE can transmit one uplink PTRS port by associating it with the first DMRS port 4. Or if the Antenna ports field indicates codepoint 5, the UE can transmit one uplink PTRS port in association with a DMRS port (or layer) transmitted to PUSCH antenna port 1000. If the Antenna ports field indicates codepoint 11, the UE can transmit one uplink PTRS port in association with a second DMRS port 5. Or if the Antenna ports field indicates codepoint 11, the UE can transmit one uplink PTRS port in association with a DMRS port (or layer) transmitted to PUSCH antenna port 1001. If the Antenna ports field indicates codepoint 17, the UE can transmit one uplink PTRS port in association with a third DMRS port 10. Or if the Antenna ports field indicates codepoint 17, the UE can transmit one uplink PTRS port in association with a DMRS port (or layer) transmitted to PUSCH antenna port 1002.[Table 27] is only one example of the above-described upper layer parameters. Similarly, for other upper layer parameter settings, codepoints can be configured to indicate the same DMRS port but different PUSCH antenna port groups to which the PTRS is associated. If there are not enough codepoints for this, only the codepoints for indicating some DMRS ports can be defined as multiple codepoints for indicating different PUSCH antenna port groups.

[0339] In one embodiment, a new table can be configured to define DMRS ports indicated by the Antenna ports field. For example, a new table can be defined based on the DMRS configuration and the number of scheduled PUSCH layers using the method of Option 2. The DMRS port associated with the PTRS port can be determined based on the newly defined table.

[0340] [Option 2] can be used to determine the DMRS port associated with a single PTRS port that can be associated with multiple DMRS ports, not only when supporting one PTRS port, but also when supporting two PTRS ports.

[0341] The terminal can determine that one of the two PTRS ports can be associated with two layers, and the other PTRS port can be associated with one layer. To determine which layer (or DMRS port) is associated with the PTRS port that can be associated with both layers, the terminal can refer to the table for DMRS port indications, which can be configured as in [Option 2].

[0342] As a specific example, let us assume that the DMRS port is determined according to [Table 27] as described above, and the precoder applied to the scheduled codebook-based PUSCH is as defined in [Table 25]. If is indicated, the first layer and the third layer can be associated with PTRS port 0 according to [Method 1] according to the PUSCH antenna port described above, and the second layer can be associated with PTRS port 1 according to [Method 1]. Here, since PTRS port 1 can be transmitted in association with the second layer, there is no need to indicate a separate PTRS-DMRS association. However, since PTRS port 0 must be transmitted in association with either the first layer or the third layer, [Table 27] can be referred to to indicate the association. For example, if the Antenna ports field in the same DCI that schedules the corresponding PUSCH indicates codepoint 3, the DMRS CDM group without data can be indicated as 3, DMRS port 0, DMRS port 1, and DMRS port 6, and the number of front-load symbols can be indicated as 2, and PTRS port 0 can be transmitted in association with the first layer among the first layer and the third layer. This is because PTRS port 0 is the first of the two layers that it can be associated with. If the Antenna ports field in the same DCI that schedules the corresponding PUSCH indicates codepoint 9, the DMRS CDM group without data can be indicated as 3, DMRS port 0, DMRS port 1, DMRS port 6, and the number of front-load symbols can be indicated as 2, and PTRS port 0 can be transmitted in association with the third layer among the first layer and the third layer. This is because PTRS port 0 is the second of the two layers that it can be associated with. In this way, if two PTRS ports are supported for the corresponding terminal and the DMRS ports are indicated based on [Table 27], codepoints 12 to 17 can be reserved and not used.Alternatively, when two PTRS ports are supported in the terminal as shown in [Table 43], the transform precoder is set to disable, the dmrs-Type is set to 2, the enhanced-dmrs-Type is not set, and the maxLength is set to 2, and the Antenna ports field consisting of 5 bits is indicated by the DCI, a table for determining the DMRS port can be defined when the rank of the PUSCH scheduled with the same DCI including the Antenna ports field is 3.

[0343] [Table 43]

[0344]

[0345] Or, in the same way as when the number of PTRS ports supported in advance is 1, the DMRS port is indicated using [Table 27], and if the Antenna ports field in the same DCI that schedules the corresponding PUSCH indicates code point 15, the DMRS CDM group without data can be indicated as 3, DMRS port 0, DMRS port 1, DMRS port 6, and the number of front-load symbols can be indicated as 2, and PTRS port 0 can be transmitted in association with the third layer among the first layer and the third layer. If the DMRS port associated with PTRS port 0 is determined in this way, code points 6 to 11 can be reserved without being used.

[0346] In one embodiment, when two PTRS ports are supported, a new table can be configured to determine the DMRS port associated with a PTRS port that can be associated with multiple DMRS ports. For example, the method of Option 2 can be used to define a new table based on the DMRS configuration and the number of scheduled PUSCH layers. Based on the newly defined table, the DMRS port associated with a PTRS port that can be associated with multiple DMRS ports can be determined.

[0347] [Option 3] The terminal can use the reserved bits of the Antenna ports field as the PTRS-DMRS association field, or use the reserved bits of the Antenna ports field together with the PTRS-DMRS association field to determine the DMRS port associated with the PTRS.

[0348] If, depending on the layer of the scheduled PUSCH, some of the code points indicated by the Antenna ports field may be reserved and not indicate DMRS ports. For example, if the transform precoder is set to disable, the dmrs-Type is set to 2, the enhanced-dmrs-Type is not set, and the maxLength is set to 2, and the 5-bit Antenna ports field is indicated by DCI, if the rank of the PUSCH scheduled with the same DCI including the Antenna ports field is 3, code points 0 to 5 are used to indicate DMRS ports, and code points 6 to 31 are reserved. In other words, it can be understood that only 3 bits out of 5 bits are used to indicate DMRS ports of the 3-layer PUSCH in this case, and 2 bits can be reserved. The bits that can be reserved in this way can be used for the PTRS-DMRS association field, and only the remaining Antenna ports field can be used to indicate DMRS ports. Of course, if the number of layers of the scheduled PUSCH is not 3, the number of bits of the Antenna ports field used is defined according to the number of scheduled layers, and only the remaining reserved bits are used for PTRS-DMRS association. For example, if the upper layer parameters are set as in the example above (transform precoder is set to disable, dmrs-Type is set to 2, enhanced-dmrs-Type is not set, and maxLength is set to 2) and the number of layers of the scheduled PUSCH is 1, all 5 bits of the Antenna ports field can be used to indicate DMRS ports, and no bits can be allocated for PTRS-DMRS association.If a reserved bit in the Antenna ports field cannot be secured for a specific scheduling situation, the reserved bit may be secured without using a code point to indicate some DMRS ports.

[0349] <Example 5: Method for transmitting a phase tracking reference signal when a terminal supporting three transmission antennas transmits a PUSCH based on a configured grant>

[0350] Hereinafter, according to one embodiment of the present disclosure, methods for transmitting PTRS when transmitting a configured grant-based PUSCH (hereinafter, CG PUSCH) when a terminal is capable of uplink transmission using three transmission antennas are specifically described.

[0351] If a UE supports 3 transmit antennas for uplink signal transmission based on 3 transmit antennas (for example, the base station configures a new RRC parameter for 3Tx UL transmission in the UE) and supports CG PUSCH based on RRC configuration, the UE can understand the PTRS-DMRS association value for the CG PUSCH as '0'. At this time, the UE can refer to the antennaPort configured in rrc-ConfiguredUplinkGrant in ConfiguredGrantConfig to determine the DMRS port of the CG PUSCH. The UE can determine the DMRS port to which the PTRS port is associated by combining the DMRS port of the CG PUSCH and the PTRS-DMRS association determined as '0'. At this time, the DMRS port can be determined by referring to a new table for additionally indicating the DMRS port to which the PTRS port can be associated, as described in the fourth embodiment above. It is assumed that the UE transmits a CG PUSCH of rank 3 and supports one PTRS port. At this time, if the upper layer parameter antennaPort is set to 2 and the PUSCH antenna port group associated with the DMRS port and PTRS is determined by referring to the newly defined [Table 26], the UE can determine DMRS ports 2, 3, and 6, which have 2 DMRS CDM groups without data of the corresponding CG PUSCH, as DMRS ports, and can determine the number of front-load symbols to 2. In addition, one PTRS port can be associated with one DMRS port included in the first PUSCH antenna port group, and since the PTRS-DMRS association value is considered as '0', the UE can determine that DMRS port 2, which is the first DMRS port among DMRS port 2 or DMRS port 6 included in the first PUSCH antenna port group, is associated with the PTRS port.

[0352] As another example, the DMRS port associated with a PTRS port can be determined by referring to a table for determining a newly defined DMRS port and the configured antennaPort value without considering the PTRS-DMRS association value for determining the DMRS port to which a separate PTRS is associated. As in the previous example, assume that the UE transmits a CG PUSCH of rank 3 and supports one PTRS port. In this case, if the upper layer parameter antennaPort is set to 13 and the newly defined [Table 27] is referred to to determine the DMRS port and the DMRS port associated with the PTRS port, the UE can determine DMRS ports 0, 1, and 2, which have 3 DMRS CDM groups without data for the corresponding CG PUSCH, as DMRS ports, and can determine the number of front-load symbols to be 1. In addition, since one PTRS port is instructed to be associated with the third DMRS port, the PTRS port can be transmitted in association with DMRS port 2.

[0353] FIG. 3 is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0354] Referring to FIG. 3, the terminal may include a transceiver, which refers to a terminal receiving unit (1300) and a terminal transmitting unit (1310), a memory (not shown), and a terminal processing unit (1305, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver units (1300, 1310), the memory, and the terminal processing unit (1305) of the terminal may operate. However, the components of the terminal are not limited to the examples described above. For example, the terminal may include more or fewer components than the components described above. In addition, the transceiver unit, the memory, and the processor may be implemented in the form of a single chip.

[0355] A transceiver unit can transmit and receive signals to and from a base station. The signals may include control information and data. To this end, the transceiver unit may include an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver unit, and the components of the transceiver unit are not limited to the RF transmitter and RF receiver.

[0356] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit a signal output from the processor through the wireless channel.

[0357] Memory can store programs and data necessary for the terminal's operation. Furthermore, memory can store control information or data included in signals transmitted and received by the terminal. Memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0358] Additionally, the processor can control a series of processes to enable the terminal to operate according to the aforementioned embodiments. For example, the processor can receive DCI consisting of two layers and control components of the terminal to simultaneously receive multiple PDSCHs. There may be multiple processors, and the processors can perform terminal component control operations by executing programs stored in memory.

[0359] FIG. 4 is a diagram illustrating the structure of a base station in a wireless communication system according to an embodiment of the present disclosure.

[0360] Referring to FIG. 4, the base station may include a transceiver, which refers to a base station receiver (1400) and a base station transmitter (1410), a memory (not shown), and a base station processor (1405, or a base station control unit or processor). Depending on the communication method of the base station described above, the transceiver (1400, 1410), the memory, and the base station processor (1405) of the base station may operate. However, the components of the base station are not limited to the examples described above. For example, the base station may include more or fewer components than the components described above. In addition, the transceiver, the memory, and the processor may be implemented in the form of a single chip.

[0361] The transceiver can transmit and receive signals with the terminal. Here, the signals may include control information and data. To this end, the transceiver may be configured with an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to the RF transmitter and RF receiver.

[0362] Additionally, the transceiver can receive a signal through a wireless channel and output it to the processor, and transmit the signal output from the processor through the wireless channel.

[0363] The memory can store programs and data necessary for the operation of the base station. Furthermore, the memory can store control information or data included in signals transmitted and received by the base station. The memory can be comprised of a storage medium, such as ROM, RAM, a hard disk, CD-ROM, or DVD, or a combination of such storage media. Furthermore, there can be multiple memories.

[0364] The processor can control a series of processes to enable the base station to operate according to the embodiments of the present disclosure described above. For example, the processor can configure two layers of DCIs containing allocation information for multiple PDSCHs and control each component of the base station to transmit them. There may be multiple processors, and the processors can perform component control operations of the base station by executing programs stored in memory.

[0365] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0366] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. The one or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. The one or more programs include instructions that cause the electronic device to execute methods according to the embodiments described in the claims or specification of the present disclosure.

[0367] These programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable read only memory (EEPROM), magnetic disc storage device, compact disc ROM (CD-ROM), digital versatile discs (DVDs) or other forms of optical storage device, magnetic cassette. Or, they may be stored in a memory configured as a combination of some or all of these. In addition, each configuration memory may be included in multiple numbers.

[0368] Additionally, the program may be stored on an attachable storage device that is accessible via a communication network, such as the Internet, an intranet, a local area network (LAN), a wide local area network (WLAN), a storage area network (SAN), or a combination thereof. Such a storage device may be connected to a device performing an embodiment of the present disclosure via an external port. Additionally, a separate storage device on the communication network may be connected to a device performing an embodiment of the present disclosure.

[0369] In the specific embodiments of the present disclosure described above, components included in the invention are expressed in the singular or plural form, depending on the specific embodiment presented. However, the singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components. Components expressed in the plural form may be composed of singular elements, or components expressed in the singular form may be composed of plural elements.

[0370] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are only specific examples to easily explain the technical contents of the present disclosure and help understand the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present disclosure are possible. In addition, the above-mentioned embodiments can be combined and operated with each other as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment can be combined with each other to operate a base station and a terminal. For example, parts of the first embodiment and the second embodiment of the present disclosure can be combined with each other to operate a base station and a terminal. In addition, although the above-mentioned embodiments have been presented based on an FDD LTE system, other modifications based on the technical idea of ​​the above-mentioned embodiments can be implemented with other systems such as a TDD LTE system, 5G, or NR system.

[0371] Meanwhile, the order of description in the drawings explaining the method of the present invention does not necessarily correspond to the order of execution, and the order of precedence may be changed or executed in parallel.

[0372] Alternatively, the drawings illustrating the method of the present invention may omit some components and include only some components within a scope that does not harm the essence of the present invention.

[0373] In addition, the method of the present invention may be implemented by combining some or all of the contents included in each embodiment within a scope that does not harm the essence of the invention.

[0374] According to one embodiment of the present disclosure, a method performed by a terminal in a wireless communication system is provided. The method may receive, from a base station, a first radio resource control (RRC) message including information regarding the number of PTRS (phase tracking reference signal) ports and a second RRC message including configuration information for supporting three transmission antennas. The method may receive, from the base station, a downlink control information (DCI) message including information regarding an association between PTRS ports and demodulation reference signal (DMRS) ports. The method may transmit a PTRS to the base station through a DMRS port corresponding to a PTRS port determined based on the number of PTRS ports and the information regarding the association between the PTRS ports and the DMRS ports.

[0375] In one embodiment, the information regarding the number of PTRS ports may include a maximum number of PTRS ports, and the maximum number of PTRS ports may include a value of 1 or 2.

[0376] In one embodiment, information regarding the association of a PTRS port and a DMRS port may include indication information consisting of 1 bit or 2 bits.

[0377] In one embodiment, the method can determine a DMRS port corresponding to a PTRS port based on two-bit indication information included in information regarding the association between the PTRS port and the DMRS port, when the maximum number of PTRS ports is 1. The method can determine a DMRS port corresponding to a PTRS port based on one-bit indication information included in information regarding the association between the PTRS port and the DMRS port, when the maximum number of PTRS ports is 2.

[0378] In one embodiment, the configuration information for supporting three transmit antennas may include SRS resource configuration information configured with four transmit antennas and a parameter for disabling a specific antenna port.

[0379] According to one embodiment of the present disclosure, a terminal performing communication in a wireless communication system may include a transceiver and at least one processor connected to the transceiver. The at least one processor may transmit, to the terminal, a first RRC message including information regarding the number of PTRS ports and a second RRC message including configuration information for supporting three transmission antennas. The at least one processor may transmit, to the terminal, a DCI message including information regarding associations between PTRS ports and DMRS ports. The at least one processor may receive a PTRS from the terminal through a DMRS port corresponding to a PTRS port determined based on the number of PTRS ports and the information regarding associations between the PTRS ports and DMRS ports.

[0380] Various embodiments of the present disclosure have been described above. The foregoing description of the present disclosure is for illustrative purposes only, and the embodiments of the present disclosure are not limited to the disclosed embodiments. Those skilled in the art will appreciate that the present disclosure can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present disclosure. The scope of the present disclosure is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present disclosure.

[0381] A device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, the term "non-transitory storage medium" simply means a tangible device that does not contain signals (e.g., electromagnetic waves). This term does not distinguish between cases where data is permanently stored in the storage medium and cases where data is temporarily stored. For example, a "non-transitory storage medium" may include a buffer in which data is temporarily stored.

[0382] According to one embodiment, the method according to various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) through an application store or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., a downloadable app) may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

Claims

1. In a method performed by a terminal in a wireless communication system, A step of receiving a first radio resource control (RRC) message including information about the number of PTRS (phase tracking reference signal) ports from a base station and a second RRC message including configuration information for supporting three transmission antennas; A step of receiving a DCI (downlink control information) message including information regarding the correlation of the PTRS port and the DMRS (demodulation reference signal) port from the base station; and A method comprising: transmitting a PTRS to the base station through a DMRS port corresponding to the PTRS port determined based on information about the number of PTRS ports and the correlation between the PTRS port and the DMRS port; 2. In paragraph 1, Information about the number of PTRS ports includes the maximum number of PTRS ports, A method wherein the maximum number of PTRS ports includes a value of 1 or 2.

3. In paragraph 1, A method in which information regarding the association of the PTRS port and the DMRS port includes instruction information consisting of 1 bit or 2 bits.

4. In paragraph 2, When the maximum number of PTRS ports is 1, a step of determining the DMRS port corresponding to the PTRS port based on 2-bit instruction information included in information regarding the association of the PTRS port and the DMRS port; and A method comprising: a step of determining the DMRS port corresponding to the PTRS port based on indication information consisting of 1 bit included in information regarding the association of the PTRS port and the DMRS port, when the maximum number of PTRS ports is 2; 5. In paragraph 1, The configuration information for supporting the above three transmitting antennas is: A method comprising: sounding reference signal (SRS) resource configuration information comprising four transmitting antennas and parameters for disabling specific antenna ports.

6. In a method performed by a base station in a wireless communication system, A step of transmitting a first RRC (radio resource control) message including information about the number of PTRS (phase tracking reference signal) ports to a terminal and a second RRC message including configuration information for supporting three transmission antennas; A step of transmitting a DCI (downlink control information) message including information regarding the correlation of the PTRS port and the DMRS (demodulation reference signal) port to the terminal; A method comprising: receiving a PTRS from the terminal through a DMRS port corresponding to the PTRS port determined based on information about the number of PTRS ports and the correlation between the PTRS port and the DMRS port; 7. In paragraph 6, Information about the number of PTRS ports includes the maximum number of PTRS ports, A method wherein the maximum number of PTRS ports includes a value of 1 or 2.

8. In paragraph 6, A method in which information regarding the association of the PTRS port and the DMRS port includes instruction information consisting of 1 bit or 2 bits.

9. In paragraph 7, When the maximum number of PTRS ports is 1, a step of determining the DMRS port corresponding to the PTRS port based on 2-bit instruction information included in information regarding the association of the PTRS port and the DMRS port; and A method comprising: a step of determining the DMRS port corresponding to the PTRS port based on indication information consisting of 1 bit included in information regarding the association of the PTRS port and the DMRS port, when the maximum number of PTRS ports is 2; 10. In paragraph 6, The configuration information for supporting the above three transmitting antennas is: A method comprising: sounding reference signal (SRS) resource configuration information comprising four transmitting antennas and parameters for disabling specific antenna ports.

11. In a terminal performing communication in a wireless communication system, Transmitter and receiver; and At least one processor connected to the transceiver, wherein the at least one processor comprises: Receive a first RRC (radio resource control) message including information about the number of PTRS (phase tracking reference signal) ports from a base station and a second RRC message including configuration information for supporting three transmit antennas, Receive a DCI message including information about the correlation of the PTRS port and the DMRS (demodulation reference signal) port from the base station, A terminal that transmits a PTRS to the base station through a DMRS port corresponding to the PTRS port determined based on information about the number of PTRS ports and the correlation between the PTRS port and the DMRS port.

12. In paragraph 11, Information about the number of PTRS ports includes the maximum number of PTRS ports, The terminal, wherein the maximum number of PTRS ports includes a value of 1 or 2.

13. In paragraph 11, A terminal including information regarding the association of the PTRS port and DMRS port, the information including indication information consisting of 1 bit or 2 bits.

14. In paragraph 12, At least one processor, When the maximum number of PTRS ports is 1, the DMRS port corresponding to the PTRS port is determined based on the 2-bit instruction information included in the information regarding the association of the PTRS port and the DMRS port, A terminal that determines the DMRS port corresponding to the PTRS port based on indication information consisting of 1 bit included in information regarding the association of the PTRS port and the DMRS port, when the maximum number of PTRS ports is 2.

15. In paragraph 11, The configuration information for supporting the above three transmitting antennas is: A method comprising: sounding reference signal (SRS) resource configuration information comprising four transmitting antennas and parameters for disabling specific antenna ports.

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