Method and apparatus for performing downlink channel estimation based on sounding reference signal in wireless communication systems

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. The present disclosure relates to the operation of a terminal and a base station in a wireless communication system, and specifically, the present disclosure relates to a method for transmitting and receiving an uplink reference signal in a wireless communication system and an apparatus capable of performing the same. The present disclosure provides an apparatus and a method capable of effectively providing services in a mobile communication system.

Description

Technology Field

[0001] The present disclosure relates to the operation of a terminal and a base station in a wireless communication system. Specifically, the present disclosure relates to a method and apparatus for performing downlink channel estimation based on a sounding reference signal in a wireless communication system. Background Technology

[0003] Looking back at the evolution of wireless communication through successive generations, technologies have been developed primarily for human-oriented services, such as voice, multimedia, and data. Following the commercialization of 5G (5th Generation) communication systems, connected devices, which have been increasing explosively, are expected to be connected to communication networks. Examples of networked objects include vehicles, robots, drones, home appliances, displays, smart sensors installed in various infrastructures, construction machinery, and factory equipment. Mobile devices are expected to evolve into various form factors, such as augmented reality glasses, virtual reality headsets, and holographic devices. In the 6G (6th Generation) era, efforts are underway to develop improved 6G communication systems to connect hundreds of billions of devices and objects to provide diverse services. For this reason, 6G communication systems are being referred to as "beyond 5G" systems.

[0004] In the 6G communication system predicted to be realized around 2030, the maximum transmission speed is tera (i.e., 1,000 gigabit) bps (bit per second), and the wireless latency is 100 microseconds (μsec). In other words, compared to the 5G communication system, the transmission speed in the 6G communication system is 50 times faster, and the wireless latency is reduced to one-tenth.

[0005] To achieve such high data transmission speeds and ultra-low latency, 6G communication systems are being considered for implementation in the terahertz (THz) band (e.g., the 95 gigahertz (GHz) to 3 terahertz (3THz) band). Due to more severe path loss and atmospheric absorption phenomena compared to the millimeter wave (mmWave) band introduced in 5G, the importance of technologies capable of guaranteeing signal reach, or coverage, is expected to increase in the terahertz band. As key technologies to ensure coverage, new waveforms, beamforming, and multi-antenna transmission technologies such as massive Multiple-Input and Multiple-Output (MIMO), Full Dimensional MIMO (FD-MIMO), array antennas, and large-scale antennas, which are superior in terms of coverage compared to RF (Radio Frequency) devices, antennas, and OFDM (Orthogonal Frequency Division Multiplexing), must be developed. In addition, new technologies such as metamaterial-based lenses and antennas, high-dimensional spatial multiplexing technology using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS) are being discussed to improve the coverage of terahertz band signals.

[0006] In addition, to improve frequency efficiency and system network, development is underway in 6G communication systems for full duplex technology, in which uplink and downlink simultaneously utilize the same frequency resources at the same time; network technology that integrates satellites and HAPS (High-Altitude Platform Stations); network structure innovation technology that supports mobile base stations and enables network operation optimization and automation; dynamic spectrum sharing technology through collision avoidance based on spectrum usage prediction; AI-based communication technology that utilizes AI (Artificial Intelligence) from the design stage and internalizes end-to-end AI support functions to realize system optimization; and next-generation distributed computing technology that realizes services of complexity exceeding the limits of terminal computing capabilities by utilizing ultra-high performance communication and computing resources (Mobile Edge Computing (MEC), cloud, etc.). In addition, attempts are continuing to further strengthen connectivity between devices, further optimize networks, promote the softwareization of network entities, and increase the openness of wireless communication through the design of new protocols to be used in 6G communication systems, the implementation of hardware-based security environments, the development of mechanisms for the safe utilization of data, and the development of technologies regarding privacy maintenance methods.

[0007] Due to the research and development of such 6G communication systems, it is expected that a new dimension of hyper-connected experience will become possible through the hyper-connectivity of 6G communication systems, which encompasses not only connections between objects but also connections between people and objects. Specifically, it is projected that 6G communication systems will enable the provision of services such as truly immersive eXtended Reality (XR), high-fidelity mobile holograms, and digital replicas. Furthermore, services such as remote surgery, industrial automation, and emergency response, which are provided through 6G communication systems with enhanced security and reliability, will be applied in various fields including industry, healthcare, automotive, and home appliances. The problem to be solved

[0009] The disclosed embodiments aim to provide an apparatus and method capable of effectively providing services in a mobile communication system. means of solving the problem

[0011] The present invention, for solving the above-mentioned problems, is characterized in that a method for processing a control signal in a wireless communication system comprises: a step of receiving a first control signal transmitted from a base station; a step of processing the received first control signal; and a step of transmitting a second control signal generated based on the processing to the base station. Effects of the invention

[0013] The disclosed embodiments provide an apparatus and method capable of effectively providing services in a mobile communication system. Brief explanation of the drawing

[0015] FIG. 1 is a diagram showing the SRS antenna switching operation in a wireless communication system according to one embodiment of the present disclosure. FIG. 2 illustrates an example of a guard period (GP) when a terminal transmits an SRS for antenna switching purposes in a wireless communication system according to one embodiment of the present disclosure. FIG. 3 illustrates examples of cases in which an SRS resource for SRS AS is transmitted without a separate GP in a wireless communication system according to one embodiment of the present disclosure. FIG. 4 illustrates an example of a method for transmitting an SRS resource for antenna switching without a GP by borrowing a Tx connected to another CC in a wireless communication system according to one embodiment of the present disclosure. FIG. 5 illustrates an example of a method for transmitting an SRS resource for antenna switching purposes by borrowing a Tx connected to another CC in a wireless communication system according to one embodiment of the present disclosure and adding a reduced number of GPs. FIG. 6 illustrates the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure. FIG. 7 illustrates the structure of a base station in a wireless communication system according to one embodiment of the present disclosure. Specific details for implementing the invention

[0016] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings.

[0017] In describing the embodiments, technical details that are well known in the art to which this disclosure belongs and are not directly related to this disclosure are omitted. This is intended to convey the essence of this disclosure more clearly without obscuring it by omitting unnecessary explanations.

[0018] For the same reason, some components in the attached drawings have been exaggerated, omitted, or schematically depicted. Additionally, the dimensions of each component do not entirely reflect their actual dimensions. Identical or corresponding components in each drawing have been assigned the same reference numbers.

[0019] The advantages and features of the present disclosure, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the 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. Throughout the specification, the same reference numerals refer to the same components. Furthermore, in describing the present disclosure, if it is determined that a detailed description of a related function or configuration might unnecessarily obscure the essence of the present disclosure, such detailed description is omitted. Additionally, the terms described below are defined considering their functions in the present disclosure, and these may vary depending on the intentions or conventions of the user or operator. Therefore, their definitions should be based on the content throughout the specification.

[0020] Hereinafter, a base station is an entity that performs resource allocation for terminals and may be at least one of a gNode B, eNode B, Node B, BS (Base Station), wireless access unit, base station controller, or a node on a network. A terminal may include a UE (User Equipment), MS (Mobile Station), cellular phone, smartphone, computer, or a multimedia system capable of performing communication functions. In this disclosure, a downlink (DL) refers to a wireless transmission path of a signal transmitted by a base station to a terminal, and an uplink (UL) refers to a wireless transmission path of a signal transmitted by a terminal to a base station. Furthermore, while LTE or LTE-A systems may be described as examples below, embodiments of this disclosure may also be applied to other communication systems having similar technical backgrounds or channel types. For example, 5th generation mobile communication technologies (5G, new radio, NR) developed after LTE-A may be included therein, and the 5G below may 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 made at the discretion of a person with skilled technical knowledge, without significantly departing from the scope of the present disclosure.

[0021] At this point, it will be understood that each block of the process flow diagrams and combinations of the flow diagrams can be executed by computer program instructions. Since these computer program instructions can be loaded into the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing equipment, the instructions executed through the processor of the computer or other programmable data processing equipment create means to perform the functions described in the flow diagram block(s). Since these computer program instructions can also be stored in computer-available or computer-readable memory that can be directed toward the computer or other programmable data processing equipment to implement the function in a specific way, the instructions stored in computer-available or computer-readable memory can also produce a manufactured item containing instruction means to perform the function described in the flow diagram block(s). Since computer program instructions can be loaded onto a computer or other programmable data processing equipment, instructions that perform a series of operation steps on the computer or other programmable data processing equipment to create a process executed by the computer can also provide steps for executing the functions described in the flowchart block(s).

[0022] Additionally, each block may represent a module, segment, or part of code containing one or more executable instructions for executing a specific logical function(s). It should also be noted that in some alternative execution examples, the functions mentioned in the blocks may occur out of order. For example, two blocks described in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order according to their corresponding functions.

[0023] In this embodiment, the term "part" refers to a software or hardware component such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit), and the "part" performs certain roles. However, the meaning of "part" is not limited to software or hardware. The "part" may be configured to reside in an addressable storage medium or configured to run one or more processors. Thus, as an example, the "part" includes components such as software components, object-oriented software components, class components, and task components, as well as processes, functions, attributes, 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." In addition, the components and 'parts' may be implemented to utilize one or more CPUs within the device or secure multimedia card. Also, in the embodiments, 'parts' may include one or more processors.

[0024] Wireless communication systems are evolving from providing early voice-oriented services to broadband wireless communication systems that provide high-speed, high-quality packet data services, such as communication standards like 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.

[0025] As a representative example of the above-mentioned broadband wireless communication system, the LTE system employs the Orthogonal Frequency Division Multiplexing (OFDM) method for the downlink (DL) and the Single Carrier Frequency Division Multiple Access (SC-FDMA) method for the uplink (UL). The uplink refers to a wireless link through which a terminal (User Equipment (UE) or Mobile Station (MS)) transmits data or control signals to a base station (eNode B, or base station (BS)), and the downlink refers to a wireless link through which a base station transmits data or control signals to a terminal. The above-mentioned multiple access method can distinguish the data or control information of each user by allocating and operating time-frequency resources to be sent for each user so that they do not overlap, that is, so that orthogonality is established.

[0026] As a future communication system following LTE, that is, a 5G communication system, it must be able to freely reflect the diverse requirements of users and service providers, and therefore, services that satisfy various requirements simultaneously must be supported. Services being considered for the 5G communication system include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliability Low Latency Communication (URLLC).

[0027] eMBB aims to provide data transmission speeds that are superior to those supported by existing LTE, LTE-A, or LTE-Pro. For example, in a 5G communication system, eMBB must be able to provide a peak data rate of 20 Gbps in the downlink and 10 Gbps in the uplink from the perspective of a single base station. Furthermore, while providing these peak data rates, the 5G communication system must also provide an increased user-perceived data rate. To satisfy these requirements, it necessitates improvements in various transmission and reception technologies, including enhanced Multi-Input Multi-Output (MIMO) transmission technology. Additionally, while LTE transmits signals using a maximum bandwidth of 20 MHz in the 2 GHz band, the 5G communication system can meet the data transmission speeds required by using a frequency bandwidth wider than 20 MHz in frequency bands of 3–6 GHz or above 6 GHz.

[0028] Simultaneously, mMTC is being considered to support application services such as the Internet of Things (IoT) in 5G communication systems. To efficiently provide IoT, mMTC requires support for a large number of terminal connections within a cell, improved terminal coverage, enhanced battery life, and reduced terminal costs. Since IoT devices are attached to various sensors and equipment to provide communication functions, the system must be able to support a large number of terminals within a cell (e.g., 1,000,000 terminals / km²). Furthermore, due to the nature of the service, terminals supporting mMTC are likely to be located in dead zones not covered by cells, such as building basements; therefore, they may require wider coverage compared to other services provided by 5G communication systems. Terminals supporting mMTC must consist of low-cost devices, and since it is difficult to frequently replace terminal batteries, a very long battery life of 10 to 15 years may be required.

[0029] Finally, URLLC is a mission-critical cellular-based wireless communication service. For example, consider services used for remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, and emergency alerts. Therefore, the communication provided by URLLC must offer very low latency and very high reliability. For instance, services supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds, and simultaneously 10 -5The following packet error rate requirements apply. Therefore, for services supporting URLLC, 5G systems must provide a Transmit Time Interval (TTI) smaller than other services, and at the same time, design considerations may be required to allocate a wide resource in the frequency band to ensure the reliability of the communication link.

[0030] The three 5G services, namely eMBB, URLLC, and mMTC, can be multiplexed and transmitted within a single system. In this case, different transmission and reception techniques and parameters may be used between the services to satisfy the different requirements of each service. Of course, 5G is not limited to the three services mentioned above.

[0031] Hereinafter, a / b may be understood as at least one of a or b.

[0032] The present disclosure may provide a method for efficiently transmitting a sounding reference signal (SRS) for estimating a downlink channel in a time division duplex (TDD) system, and an apparatus capable of performing the same.

[0033] [Regarding SRS]

[0034] According to various embodiments of the present disclosure, a method for estimating an uplink channel using the transmission of a terminal's Sounding Reference Signal (SRS) may be provided.

[0035] According to one embodiment of the present disclosure, a base station may set at least one SRS configuration for each uplink bandwidth part (BWP) to transmit configuration information for SRS transmission to a terminal. Additionally, the base station may set at least one SRS resource set for each SRS configuration. For example, the base station and the terminal may exchange upper signaling information as follows to transmit information regarding the SRS resource set.

[0036] - srs-ResourceSetId: SRS resource set index

[0037] - srs-ResourceIdList: A set of SRS resource indices referenced by the SRS resource set

[0038] - resourceType: This is the time-axis transmission setting for the SRS resource referenced in the SRS resource set, and can be set to one of 'periodic', 'semi-persistent', or 'aperiodic'. If set to 'periodic' or 'semi-persistent', associated CSI-RS information may be provided depending on the usage of the SRS resource set. If set to 'aperiodic', a non-periodic SRS resource trigger list and slot offset information may be provided, and associated CSI-RS information may be provided depending on the usage of the SRS resource set.

[0039] - usage: A setting regarding the usage of the SRS resource referenced in the SRS resource set, which can be set to one of 'beamManagement', 'codebook', 'nonCodebook', or 'antennaSwitching'.

[0040] - alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter settings for controlling the transmit power of an SRS resource referenced in an SRS resource set.

[0041] The terminal can understand that the SRS resources included in the set of SRS resource indices referenced in the SRS resource set follow the information set in the SRS resource set.

[0042] According to one embodiment of the present disclosure, a base station and a terminal may transmit and receive upper-layer signaling information to transmit individual configuration information for an SRS resource. For example, the individual configuration information for an SRS resource may include time-frequency axis mapping information within the slot of the SRS resource. The time-frequency axis mapping information within the slot of the SRS resource may include information regarding frequency hopping within or between slots of the SRS resource. Additionally, the individual configuration information for an SRS resource may include information regarding the time-axis transmission setting of the SRS resource. The information regarding the time-axis transmission setting of the SRS resource may be set to one of 'periodic', 'semi-persistent', or 'aperiodic'. This may be limited to having the same time-axis transmission setting as the SRS resource set containing the SRS resource. If the time axis transmission setting of an SRS resource is set to 'periodic' or 'semi-persistent', the SRS resource transmission period and slot offset (e.g., periodicityAndOffset) may additionally be included in the time axis transmission setting.

[0043] According to one embodiment of the present disclosure, a base station may activate or deactivate or trigger SRS transmission to a terminal via upper layer signaling, including RRC signaling or MAC CE signaling, or L1 signaling (e.g., DCI). For example, the base station may activate or deactivate periodic SRS transmission to the terminal via upper layer signaling. The base station may instruct the terminal to activate an SRS resource set with resourceType set to periodic via upper layer signaling, and the terminal may transmit an SRS resource referenced in the activated SRS resource set. The time-frequency axis 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. Additionally, a spatial domain transmission filter applied to the transmitted SRS resource may refer to spatial relation info set in the SRS resource, or may refer to associated CSI-RS information set in the SRS resource set containing the SRS resource. The terminal can transmit an SRS resource within an active uplink BWP for a periodic SRS resource activated through upper layer signaling.

[0044] For example, a base station can enable or disable semi-persistent SRS transmission to a terminal via upper-layer signaling. The base station can instruct the terminal to enable an SRS resource set via MAC CE signaling, and the terminal can transmit an SRS resource referenced in the enabled SRS resource set. The SRS resource set enabled via MAC CE signaling may be limited to an SRS resource set where the resourceType is set to semi-persistent. The time-frequency axis resource mapping within the slot of the SRS resource transmitted by the terminal may follow the resource mapping information set in the SRS resource, and the slot mapping, including the transmission period and slot offset, may follow the periodicityAndOffset set in the SRS resource. Additionally, the spatial domain transmission filter applied to the SRS resource transmitted by the terminal may refer to the spatial relation info set in the SRS resource, or refer to the associated CSI-RS information set in the SRS resource set containing the SRS resource. If spatial relation info is configured in the SRS resource, the terminal may determine the spatial domain transmission filter by referring to the configuration information regarding the spatial relation info transmitted via MAC CE signaling that enables semi-persistent SRS transmission, without adhering to this. The terminal may transmit the SRS resource within the uplink BWP enabled for the semi-persistent SRS resource activated via upper layer signaling.

[0045] For example, a base station can trigger an aperiodic SRS transmission to a terminal via the DCI. The base station can indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) through the SRS request field of the DCI. The terminal can understand that among the configuration information of the SRS resource set, an SRS resource set containing the aperiodic SRS resource trigger indicated via the DCI from the list of aperiodic SRS resource triggers has been triggered. The terminal can transmit the SRS resource referenced in the triggered SRS resource set. The time-frequency axis resource mapping within the slot of the SRS resource transmitted by the terminal may follow the resource mapping information set in the SRS resource. Additionally, the slot mapping of the SRS resource transmitted by the terminal may be determined through the slot offset between the PDCCH containing the DCI and the SRS resource, which may refer to the value(s) included in the set of slot offsets set in the SRS resource set. Specifically, the slot offset between the PDCCH containing the DCI and the SRS resource may be the value specified 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. Additionally, the spatial domain transmission filter applied to the SRS resource transmitted by the terminal may refer to the spatial relation info configured in the SRS resource, or may refer to the associated CSI-RS information configured in the SRS resource set containing the SRS resource.The terminal can transmit an SRS resource within an uplink BWP that is enabled for a non-periodic SRS resource triggered via DCI.

[0046] When a base station triggers aperiodic SRS transmission to a terminal via DCI, a minimum time interval may be required between the PDCCH containing the DCI triggering the aperiodic SRS transmission and the transmitted SRS so that the terminal can apply configuration information for the SRS resource and transmit the SRS. The time interval for the terminal's SRS transmission can be defined as the number of symbols between the last symbol of the PDCCH containing the DCI triggering the aperiodic SRS transmission and the first symbol mapped to the first transmitted SRS resource(s). The minimum time interval can be determined by referencing the PUSCH preparation procedure time required for the terminal to prepare for PUSCH transmission. Additionally, the minimum time interval may have different values ​​depending on the usage of the SRS resource set containing the transmitted SRS resource. For example, the minimum time interval can be determined by N2 symbols defined by considering the terminal's processing capability based on the terminal's capability, referencing the terminal's PUSCH preparation procedure time. In addition, considering the usage of the SRS resource set including the SRS resource transmitted by the terminal, 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 transmits an aperiodic SRS when the time interval for the aperiodic SRS transmission is greater than or equal to the minimum time interval, and can ignore the DCI that triggers the aperiodic SRS when the time interval for the aperiodic SRS transmission is less than the minimum time interval.

[0047] [Table 1]

[0049]

[0050]

[0051] The spatialRelationInfo setting information in [Table 1] above can be applied to the beam used for SRS transmission by referencing a single reference signal and the beam information of that reference signal. For example, the spatialRelationInfo setting may include information such as that in [Table 2] below. However, the spatialRelationInfo setting is not limited to the examples in [Table 2] below.

[0052] [Table 2]

[0054]

[0055] Referring to the spatialRelationInfo setting above, the terminal may receive from the base station a CSI-RS index or an SRS index as 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. The upper signaling referenceSignal is setting information indicating which reference signal's beam information to reference for the corresponding SRS transmission, and ssb-Index may mean the SS / PBCH block index, csi-RS-Index may mean the CSI-RS index, and srs may mean the SRS index. If the value of the upper signaling referenceSignal is set to 'ssb-Index', the terminal may apply the receiving beam used when receiving the SS / PBCH block corresponding to ssb-Index as the transmitting beam for the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'csi-RS-Index', the terminal can apply the receiving beam used when receiving the CSI-RS corresponding to csi-RS-Index as the transmitting beam for the corresponding SRS transmission. If the value of the upper signaling referenceSignal is set to 'srs', the terminal can apply the transmitting beam used when transmitting the SRS corresponding to srs as the transmitting beam for the corresponding SRS transmission.

[0056] [SRS: Antenna switching]

[0057] The following describes the SRS for antenna switching.

[0058] The SRS transmitted from the terminal can be used by the base station to acquire Channel State Information (DL CSI) information (e.g., DL CSI acquisition). As a specific example, in a single-cell or multi-cell (e.g., carrier aggregation (CA)) situation based on Time Division Duplex (TDD), the Base Station (BS) can measure the SRS transmitted from the UE after scheduling the transmission of the SRS to the User Equipment (UE). In this case, the base station can assume reciprocity between the DL (downlink) and UL (uplink) channels and consider the uplink channel information estimated based on the SRS transmitted from the terminal as downlink channel information, and use this to perform scheduling of downlink signals / channels for the terminal. At this time, the terminal can receive a setting from the base station for the use of the SRS for acquiring downlink channel information as antenna switching.

[0059] For example, according to the standard (e.g., 3gpp TS38.214), the use of the SRS can be configured for the base station and / or terminal using a higher layer parameter (e.g., the usage of the RRC parameter SRS-ResourceSet). Here, the use of the SRS can be configured for beam management, codebook transmission, non-codebook transmission, antenna switching, etc.

[0060] As described above, if the terminal receives the parameter 'usage' within the upper layer signaling SRS-ResourceSet from the base station as 'antennaSwitching', the terminal may receive at least one upper layer signaling setting from the base station according to the reported terminal capability. In this case, the terminal may report 'supportedSRS-TxPortSwitch' as ​​the terminal capability, and the value may be as follows. In the following, 'mTnR' may refer to the terminal capability to support transmission through m antennas and reception through n antennas.

[0061] - 't1r2': A terminal capability report value indicating that the terminal is capable of 1T2R operation

[0062] - 't1r1-t1r2': A terminal capability report value indicating that the terminal is capable of 1T1R or 1T2R operation

[0063] - 't2r4': A terminal capability report value indicating that the terminal is capable of 2T4R operation.

[0064] - 't1r4': A terminal capability report value indicating that the terminal is capable of 1T4R operation

[0065] - 't1r6': A terminal capability report value indicating that the terminal is capable of 1T6R operation

[0066] - 't1r8': A terminal capability report value indicating that the terminal is capable of 1T8R operation

[0067] - 't2r6': A terminal capability report value indicating that the terminal is capable of 2T6R operation

[0068] - 't2r8': A terminal capability report value indicating that the terminal is capable of 2T8R operation

[0069] - 't4r8': A terminal capability report value indicating that the terminal is capable of 4T8R operation.

[0070] - 't1r1-t1r2-t1r4': A terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, or 1T4R operation.

[0071] - 't1r4-t2r4': A terminal capability report value indicating that the terminal is capable of 1T4R or 2T4R operation.

[0072] - 't1r1-t1r2-t2r2-t2r4': A terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, 2T2R, or 2T4R operations.

[0073] - 't1r1-t1r2-t2r2-t1r4-t2r4': A terminal capability report value indicating that the terminal is capable of 1T1R, 1T2R, 2T2R, 1T4R, or 2T4R operations.

[0074] - 't1r1': A terminal capability report value indicating that the terminal is capable of 1T1R operation

[0075] - 't2r2': A terminal capability report value indicating that the terminal is capable of 2T2R operation.

[0076] - 't1r1-t2r2': A terminal capability report value indicating that the terminal is capable of 1T1R or 2T2R operation.

[0077] - 't4r4': A terminal capability report value indicating that the terminal is capable of 4T4R operation.

[0078] - 't1r1-t2r2-t4r4': A terminal capability report value indicating that the terminal is capable of 1T1R, 2T2R, or 4T4R operation.

[0080] When a terminal performs antenna switching operations, that is, when the terminal transmits different SRS resources connected to different antenna port(s), a time interval of approximately 15 μs may generally be required between two adjacent SRS resources among all transmitted SRS resources. Taking this into consideration, a (minimum) guard period as shown in [Table 3] below may be defined.

[0081] [Table 3]

[0082]

[0084] In [Table 3], μ represents numerology, and represents the subcarrier spacing, and Y can represent the number of OFDM symbols representing the guard interval, i.e., the length of the guard interval. Referring to [Table 3], the guard interval can be set based on the parameter μ, which determines the numerology. During the guard interval, the terminal is configured not to transmit any other signals, and the guard interval can be configured to be used entirely for antenna switching.

[0085] For example, a guard interval can be set between the transmission times of two adjacent SRS resources, taking into account SRS resources transmitted at different OFDM symbol positions within the same slot.

[0086] As another example, if a terminal is configured with two SRS resource sets for antenna switching, and these two SRS resource sets are configured or triggered to be transmitted in two consecutive slots, and the terminal reports the capability to transmit SRS at every OFDM symbol position within the slot, the terminal can expect that there will be at least Y OFDM symbols for the protection interval for antenna switching between the last OFDM symbol transmitted in the first slot where SRS transmission for the first SRS resource set is performed, and the first OFDM symbol transmitted in the second slot where SRS transmission for the second SRS resource set is performed, based on [Table 3] above. That is, the actual time difference between the two SRS transmissions may be greater than or equal to Y OFDM symbols.

[0087] - Regarding such a slot-to-slot protection interval, similar to the protection interval between two SRS resources within a slot described above, if the actual time difference between the last SRS transmission of the first slot and the first SRS transmission of the next slot within two consecutive slots is Y OFDM symbols, the terminal may not transmit any signal during the corresponding Y OFDM symbol interval.

[0088] - For such an inter-slot guard interval, if the actual time difference between the last SRS transmission of the first slot and the first SRS transmission of the next slot within two consecutive slots is Y OFDM symbols, and if both SRS transmissions before and after the inter-slot guard interval are dropped (all canceled) due to overlap with other signals, the terminal may determine that the inter-slot guard interval defined by Y OFDM symbols has been dropped (canceled) by applying the same priority as the SRS transmissions before and after the guard interval, and if it is determined that it has been dropped, it may perform uplink transmission in this inter-slot guard interval.

[0090] For all antenna switching methods described above, the terminal can expect that all SRS resources within all SRS resource sets, where the usage of the upper layer signaling within the SRS resource set is set to 'antennaSwitching', will be configured with the same number of SRS ports from the base station.

[0091] Regarding the antenna switching method based on the aforementioned 1T24, 1T4R, 2T4R, 1T6R, 1T8R, 2T6R, 2T8R, and 4T8R operations, the terminal may not expect that two or more of the SRS resource sets, for which the usage of the upper layer signaling from the base station is set to 'antennaSwitching', are set or triggered in the same slot.

[0092] Regarding the antenna switching method based on the above-described 1T1R, 2T2R, and 4T4R operations, the terminal may not expect that two or more of the SRS resource sets, in which the usage of the upper layer signaling from the base station is set to 'antennaSwitching', are set or triggered on the same OFDM symbol.

[0093] FIG. 1 is a diagram showing the SRS antenna switching operation in a wireless communication system according to one embodiment of the present disclosure.

[0094] Referring to FIG. 1, the terminal may be in a situation where it operates in 1T4R and has received two non-periodic SRS resource sets (e.g., SRS resource set #0 and #1). The terminal receives a PDCCH from a base station (100) and may be instructed to trigger a non-periodic SRS for SRS resource set #0 (110) and SRS resource set #1 (120) through the PDCCH. At this time, the slot offset value for SRS resource set #0 (110) may be set to slotOffset, which is an upper layer signaling, and the value may be 1. Additionally, the terminal may perform a non-periodic SRS transmission for SRS resource set #0 at a position one slot after the slot in which the PDCCH was received (e.g., at slot #1). Additionally, the slot offset value for SRS resource set #1 (120) may be set to slotOffset, which is an upper layer signaling, and the value may be 2. Additionally, the terminal may perform a non-periodic SRS transmission for SRS resource set #1 at a position two slots after the slot in which the PDCCH was received (e.g., at slot #2).

[0095] SRS resource #0 (111) and SRS resource #1 (112) included in SRS resource set #0 (110) can be transmitted at different OFDM symbol locations within slot #1, and there may be Y number of OFDM symbols as a guard interval between SRS resource #0 and #1 (113). Additionally, when transmitting for SRS resource #0 (130), the terminal can perform SRS transmission by connecting one SRS port to the terminal's first receiving antenna port (135). When transmitting for SRS resource #1 (140), the terminal can perform SRS transmission by connecting one SRS port to the terminal's second receiving antenna port (145).

[0096] SRS resource #2 (121) and SRS resource #3 (122) included in SRS resource set #1 (120) are transmitted at different OFDM symbol locations within slot #1, and there may be Y number of OFDM symbols as a guard interval between SRS resource #2 and #3 (123). Additionally, when transmitting for SRS resource #2 (150), the terminal can perform SRS transmission by connecting one SRS port to the terminal's third receiving antenna port (155). When transmitting for SRS resource #3 (160), the terminal can perform SRS transmission by connecting one SRS port to the terminal's fourth receiving antenna port (165).

[0097] By connecting the four SRS resources #0 to #3 described above to the receiving antenna ports of different terminals and transmitting SRS, the terminal can transmit SRS from all different receiving antenna ports so that it can acquire channel information connected to all receiving antennas of the terminal. In addition, by the terminal transmitting SRS from all different receiving antenna ports, the base station can acquire channel information between the base station and the terminal and utilize it for uplink or downlink scheduling.

[0099] [Regarding Terminal Capability Reporting]

[0100] In LTE and NR, a terminal can perform a procedure to report the capabilities supported by the terminal to the base station while connected to the serving base station. In the description below, this is referred to as a UE capability report.

[0101] A base station may transmit a UE capability enquiry message requesting capability reporting to a connected terminal. The UE capability enquiry message may include a request for terminal capability specific to the base station's RAT (radio access technology) type. The request for terminal capability specific to the RAT type may include information such as supported frequency band combinations. Furthermore, in the case of the UE capability enquiry message, multiple UE capabilities for each RAT type may be requested through a single RRC message container transmitted by the base station, or the base station may transmit the UE capability enquiry message, which includes the request for each RAT type, to the terminal multiple times. That is, the UE capability inquiry may be repeated multiple times within a single message, and the terminal may construct and report the corresponding UE capability information message multiple times. In next-generation mobile communication systems, UE capability requests can be made for NR, LTE, EN-DC (E-UTRA - NR dual connectivity), and MR-DC (Multi-RAT dual connectivity). Additionally, while the UE capability enquiry message may generally be transmitted initially after the terminal connects with the base station, the base station may also request it under any conditions when necessary.

[0102] According to one embodiment, a terminal that receives a request to report UE capability from a base station can configure terminal capability according to the RAT type and band information requested from the base station. The method by which a terminal configures UE capability in an NR system may be as follows.

[0103] 1. If the terminal receives a list of LTE and / or NR bands from the base station via a UE capability request, the terminal can configure a band combination (BC) for EN-DC and NR stand alone (SA). That is, it can configure a candidate list of BCs for EN-DC and NR SA based on the bands requested from the base station via FreqBandList. Additionally, the bands may have priority in the order listed in FreqBandList.

[0104] 2. If the base station requests a UE capability report by setting the "eutra-nr-only" flag or the "eutra" flag, the terminal may completely remove NR SA BCs from the above-mentioned list of configured BC candidates. This operation may occur only when the LTE base station (eNB) requests the "eutra" capability.

[0105] 3. Subsequently, the terminal may remove fallback BCs from the candidate list of BCs configured in the above step. Here, a fallback BC refers to a BC that can be obtained by removing a band corresponding to at least one SCell from any BC; this step may be omitted because the BC before removing the band corresponding to at least one SCell already covers the fallback BC. This step applies to MR-DC as well, that is, to LTE bands. The BCs remaining after this step may be the final "candidate BC list."

[0106] 4. The terminal can select BCs to report by selecting BCs that match the requested RAT type from the final "Candidate BC List" above. In this step, the terminal can configure the supportedBandCombinationList in a predetermined order. That is, the terminal can configure the BCs and UE capabilities to report according to the pre-configured rat-Type order (nr -> eutra-nr -> eutra). Additionally, it can configure a featureSetCombination for the configured supportedBandCombinationList and construct a list of "Candidate Feature Set Combinations" from the Candidate BC List from which the list of fallback BCs (containing capabilities of the same or lower level) has been removed. The above "Candidate Feature Set Combinations" include feature set combinations for both NR and EUTRA-NR BCs and can be obtained from feature set combinations of the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0107] 5. Additionally, if the requested rat Type is eutra-nr and has an influence, featureSetCombinations can be included in both the UE-MRDC-Capabilities and UE-NR-Capabilities containers. However, the NR feature set can only be included in UE-NR-Capabilities.

[0108] After terminal capability is configured, the terminal can transmit a terminal capability information message containing the terminal capability to the base station. Based on the terminal capability received from the terminal, the base station can subsequently perform appropriate scheduling and transmission / reception management for the terminal.

[0109] Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The contents of the present disclosure are applicable to FDD and TDD systems. In the present disclosure, upper signaling (or upper layer signaling) is a signal transmission method transmitted from a base station to a terminal using a physical layer downlink data channel, or from a terminal to a base station using a physical layer uplink data channel, and may be referred to as RRC signaling, PDCP signaling, or a MAC (medium access control) control element (MAC CE).

[0110] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied having a specific format, or the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied including a specific indicator indicating whether cooperative communication is applied, or the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied being scrambled with a specific RNTI, or assuming the application of cooperative communication in a specific section indicated to an upper layer. For convenience of explanation thereafter, the case in which the terminal receives a PDSCH to which cooperative communication is applied based on conditions similar to those above will be referred to as the NC-JT case.

[0111] In the following disclosure, determining the priority between A and B may be referred to in various ways, such as selecting the one with the higher priority according to a predetermined priority rule and performing the corresponding action, or omitting or dropping the action for the one with the lower priority.

[0112] In the following disclosure, the examples are described through a number of embodiments, but these are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0113] For convenience in the following description of the present disclosure, cells, transmission points, panels, beams, and / or transmission directions that can be distinguished through upper layer / L1 parameters such as TCI state or spatial relation information, or indicators such as cell ID, TRP ID, and panel ID, may be described uniformly as TRP (transmission reception point), beam, or TCI state. Accordingly, in actual application, TRP, beam, or TCI state can be appropriately replaced with one of the above terms.

[0114] In the present disclosure, when determining whether cooperative communication is applied, the terminal may use various methods, such as the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied having a specific format, or the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied including a specific indicator indicating whether cooperative communication is applied, or the PDCCH(s) that allocate the PDSCH to which cooperative communication is applied being scrambled with a specific RNTI, or assuming the application of cooperative communication in a specific section indicated to an upper layer. For convenience of explanation thereafter, the case in which the terminal receives a PDSCH to which cooperative communication is applied based on conditions similar to those above will be referred to as the NC-JT case.

[0115] Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. Hereinafter, a base station is an entity that performs resource allocation for terminals and may be at least one of a gNode B, gNB, eNode B, Node B, BS (Base Station), wireless access unit, base station controller, or a node on a network. A terminal may include a UE (User Equipment), MS (Mobile Station), cellular phone, smartphone, computer, or a multimedia system capable of performing communication functions. Although embodiments of the present disclosure are described below using a 5G system as an example, embodiments of the present disclosure may be applied to other communication systems having similar technical backgrounds or channel types. For example, LTE or LTE-A mobile communication and mobile communication technologies developed after 5G may be included therein. Accordingly, embodiments of the present disclosure may be applied to other communication systems with some modifications without significantly departing from the scope of the present disclosure, as judged by a person skilled in the art. The contents of the present disclosure are applicable to FDD and TDD systems.

[0116] Furthermore, in describing the present disclosure, if it is determined that a detailed description of related functions or configurations could unnecessarily obscure the essence of the present disclosure, such detailed description is omitted. Additionally, the terms described below are defined in consideration of their functions within the present disclosure, and these definitions may vary depending on the intentions or practices of the user or operator. Therefore, their definitions should be based on the content throughout this specification.

[0117] In describing the present disclosure below, the term "upper layer signaling" may refer to a signaling corresponding to at least one or a combination of at least one of the following signalings.

[0118] - MIB (Master Information Block)

[0119] - SIB (System Information Block) or SIB

[0120] - RRC (Radio Resource Control)

[0121] - MAC (Medium Access Control) CE (Control Element)

[0122] In addition, L1 signaling may be a signaling corresponding to at least one or a combination of at least one of the following physical layer channels or signaling methods using signaling.

[0123] - PDCCH (Physical Downlink Control Channel)

[0124] - DCI (Downlink Control Information)

[0125] - Terminal-specific (UE-specific) DCI

[0126] - Group common DCI

[0127] - Common DCI

[0128] - Scheduling DCI (e.g., DCI used for the purpose of scheduling downlink or uplink data)

[0129] - Non-scheduling DCI (e.g., DCI not intended for scheduling downlink or uplink data)

[0130] - PUCCH (Physical Uplink Control Channel)

[0131] - UCI (Uplink Control Information)

[0132] In the following disclosure, determining the priority between A and B may be referred to in various ways, such as selecting the one with the higher priority according to a predetermined priority rule and performing the corresponding action, or omitting or dropping the action for the one with the lower priority.

[0133] The term "slot" used in the present disclosure below is a general term that may refer to a specific time unit corresponding to TTI (Transmit Time Interval), and specifically, it may mean a slot used in a 5G system, or a slot or subframe used in a 4G LTE system.

[0134] In the following disclosure, the examples are described through a number of embodiments, but these are not independent, and one or more embodiments may be applied simultaneously or in combination.

[0136] According to one embodiment of the present disclosure, a base station may be composed of more antennas than a terminal and may transmit DL signals using more transmitting antenna ports. The base station may estimate a DL channel between the base station and the terminal to support downlink (DL) MIMO using multiple antennas for the terminal. The base station may precode a DL physical channel (e.g., PDSCH) to be transmitted to the terminal by calculating or determining a precoder through the estimated DL channel between the base station and the terminal. Since DL MIMO transmission based on such precoding performs beamforming using multiple antennas, the base station can obtain a multi-antenna array gain due to the beamforming method. That is, when the base station performs DL physical channel transmission considering the DL channel between the base station and the terminal, the base station can obtain higher spectral efficiency.

[0137] Two methods may be used to estimate the DL channel between a base station and a terminal in a TDD system according to one embodiment of the present disclosure.

[0138] According to one embodiment of the present disclosure, in a first method for estimating a DL channel between a base station and a terminal in a TDD system, the base station transmits a reference signal (RS) (e.g., a CSI-RS resource) for channel measurement to the terminal, and the terminal can calculate and determine channel state information (CSI) by receiving the reference signal from the base station. Subsequently, the terminal can report the CSI determined based on the reference signal received from the base station to the base station. At this time, since the terminal generates the CSI by referring to a defined codebook, the terminal can report a quantized DL channel to the base station rather than the actual DL channel. Accordingly, the base station can receive feedback from the terminal regarding DL channel information lost due to quantization. Additionally, the base station can select a precoder for the DL physical channel based on the CSI information received from the terminal, and apply the selected precoder to transmit the DL physical channel. A base station may transmit to a terminal a CSI-RS resource(s) consisting of the same number of ports as all transmitting antenna ports of the base station in order to support the terminal in measuring DL channels between all antenna ports of the base station and all antenna ports of the terminal to calculate CSI. For example, if the number of transmitting antenna ports of the base station is 32, the base station may transmit to the terminal a CSI-RS resource consisting of 32 ports.The terminal receives a CSI-RS resource consisting of 32 ports, estimates the channel between each base station transmission port and the terminal ports, calculates CSI information (which may consist of a precoding matrix indicator (PMI), channel quality indicator (CQI), rank indicator (RI), etc.) using the estimated channel, and feeds back the CSI information to the base station.

[0139] In a second method for estimating a DL channel between a base station and a terminal in a TDD system according to one embodiment of the present disclosure, the base station may receive an SRS from the terminal to estimate a UL channel and estimate a DL channel according to reciprocity characteristics in the TDD system. In a TDD (time division duplexing) system, since the same frequency band is divided in the time domain to support UL (uplink) and DL (downlink), reciprocity characteristics can be established between the UL channel and the DL channel. That is, in a TDD system, if one of the UL channel or the DL channel can be estimated, the other of the DL channel or the UL channel can also be estimated according to reciprocity characteristics. If the link condition between the base station and the terminal is good and the terminal's UL coverage is good, the base station may schedule an SRS for antenna switching purposes to estimate the DL channel. As described above, if a terminal is implemented with fewer RF Tx chains than the number of receiving antennas on a specific carrier of a specific band, multiple SRS resource transmissions may be required to measure the channels between all terminal receiving antennas and base station antennas. For example, if a terminal is implemented with two RF Tx chains and four receiving antennas, the terminal can use two RF Tx chains to transmit SRS resources to measure the channels between two receiving antennas and base stations at once. Therefore, the terminal must transmit at least two SRS resources to measure all four channels between receiving antennas and base stations using two RF Tx chains.When a terminal transmits two SRS resources to measure the channel between four receiving antennas and a base station using two RF Tx chains as described above, the terminal may connect the two RF Tx chains to the first receiving antenna and the second receiving antenna, respectively, to transmit the first SRS resource. Additionally, the terminal may connect the two RF Tx chains to the third receiving antenna and the fourth receiving antenna, respectively, to transmit the second SRS resource. However, this is merely an example, and it may be implemented to transmit two SRS resources by connecting the two RF Tx chains to different receiving antennas. In this case, after the terminal transmits the first SRS resource to the base station, time may be required for the terminal to connect the RF Tx chain connected to one receiving antenna (the first and second antennas in the example described above) to another receiving antenna (the third and fourth antennas in the example described above) in order to transmit the second SRS resource. This may correspond to the time consumed to switch the physical switch of the terminal or the time required for other RF circuits to switch. Therefore, when a terminal transmits multiple SRS resources included in an SRS resource set for antenna switching purposes, time may be required between each SRS resource to switch the RF Tx chain to another antenna.

[0140] According to one embodiment of the present disclosure, a base station may use at least one of two methods for estimating a DL channel. If the base station estimates a DL channel using SRS according to the second of the two methods described above, the terminal transmits the SRS considering a smaller number of terminal receiving antennas compared to the base station; therefore, the base station can estimate the DL channel with less RS overhead compared to a CSI-RS resource composed of the same number of ports as the number of base station transmitting antennas. Additionally, since the base station receives the SRS from the terminal, estimates the UL channel, and estimates the DL channel based on reciprocity, it can estimate a channel that is not quantized or has a small quantization error. Accordingly, the base station can calculate a precoder for transmitting a DL physical channel (PDSCH) based on the accurately estimated DL channel. As a result, DL throughput performance may be improved compared to when the first method is supported.

[0141] However, even if the RS overhead of the SRS used for antenna switching is small compared to the CSI-RS resource, if the number of receiving antennas of the terminal increases, the UL resource wasted may increase due to the time required for switching the RF Tx chain between SRS resources (hereinafter referred to as guard period or GP).

[0142] FIG. 2 illustrates an example of a guard period when a terminal transmits an SRS for antenna switching purposes in a wireless communication system according to one embodiment of the present disclosure. Referring to FIG. 2, it can be assumed that the guard period is 1 symbol and each SRS resource is also transmitted as 1 symbol.

[0143] Referring to FIG. 2, the first example (200) of FIG. 2 illustrates an operation in which a terminal transmits four SRS resources (201, 202, 203, 204) within an SRS resource set for 1T4R antenna switching, when the number of receiving antennas for DL ​​reception is four, and the terminal supports one RF Tx chain for one carrier of a certain band. The terminal transmits the SRS resources through the terminal's four antennas using one RF Tx chain. Thus, after the terminal transmits the first SRS resource (201) to one antenna (e.g., the first of the four antennas), the antennas can be switched during the first guard period (211) to transmit the second SRS resource (202) to another antenna (e.g., the second of the four antennas). After the first guard period (211), the terminal can transmit the second SRS resource (202) to the switched antenna (e.g., the second antenna among four antennas). Then, it can similarly switch during the second guard period (212) to transmit the third SRS resource (203) to another antenna (e.g., the third antenna among four antennas). After the second guard period (212), the terminal can transmit the third SRS resource (203) to the switched antenna (the third antenna). Then, it can similarly switch during the third guard period (213) to transmit the fourth SRS resource (204) to another antenna (e.g., the fourth antenna among four antennas). After the third guard period (213), the terminal can transmit the fourth SRS resource (204) to the switched antenna (the fourth antenna).That is, in the first example (200) of FIG. 2, three guard periods (211, 212, 213) may be required to transmit four SRS resources (201, 202, 203, 204).

[0144] Referring to FIG. 2, the second example (220) of FIG. 2 illustrates an operation in which a terminal transmits 8 SRS resources (221, 222, 223, 224, 225, 226, 227, 228) within an SRS resource set for 1T8R antenna switching, when the number of receiving antennas for DL ​​reception is 8, and the terminal supports 1 RF Tx chain. The terminal transmits SRS resources through the terminal's 8 antennas using 1 RF Tx chain. Therefore, after the terminal transmits a certain SRS resource (221, 222, 223, 224, 225, 226, or 227) to a certain antenna (e.g., the first antenna, the second antenna, the third antenna, the fourth antenna, the fifth antenna, the sixth antenna, or the seventh antenna), it may switch the antenna for a specific guard period (231, 232, 233, 234, 235, 236, or 237) to transmit another SRS resource (222, 223, 224, 225, 226, 227, or 228) to another antenna (e.g., the second antenna, the third antenna, the fourth antenna, the fifth antenna, the sixth antenna, the seventh antenna, or the eighth antenna). The terminal can transmit to the next SRS resource (222, 223, 224, 225, 226, 227, or 228) switched antenna (e.g., second antenna, third antenna, fourth antenna, fifth antenna, sixth antenna, seventh antenna, or eighth antenna) after the guard period (231, 232, 233, 234, 235, 236, or 237).That is, seven guard periods (231, 232, 233, 234, 235, 236, 237) may be required for the terminal to transmit eight SRS resources (221, 222, 223, 224, 225, 226, 227, 228).

[0145] Through the two examples in Figure 2, even if the number of RF Tx chains of the terminal does not increase relatively significantly, if the number of receiving antennas of the terminal increases, the number of SRS resources and guard periods required to transmit SRS for antenna switching for DL ​​channel estimation may increase. This means that if DL traffic is larger than UL traffic and the size of DL data to be transmitted by the base station to the terminal increases, the terminal can be implemented without significantly increasing the implementation cost by supporting more receiving antennas to increase DL spectral efficiency without increasing additional RF Tx chains.

[0147] According to one embodiment of the present disclosure, as the functionality of the RF chain of a terminal is improved, the length of time required to switch antennas may be reduced. The time required to switch antennas may refer to the time required for the terminal to physically switch the RF Tx chain from one antenna to another. For example, the time required for the terminal to switch antennas may be reduced through the optimization of RF elements, switches, or the internal circuit design of the terminal. If the time required for the terminal to switch antennas is less than the number of symbols Y defined as the guard period per subcarrier spacing, or if the ratio of the time required to switch antennas within a symbol is small, the proportion of time wasted as a guard period may increase.

[0149] According to one embodiment of the present disclosure, if the guard period for securing time to switch the antenna can be minimized when transmitting an SRS for antenna switching, the UL resources required for the terminal to transmit the SRS for antenna switching may be reduced. This can improve UL spectral efficiency and make it easier to secure UL resources for scheduling the SRS.

[0151] According to a first embodiment of the present disclosure, a method for transmitting an SRS for antenna switching is provided by determining whether a guard period is required based on the time required for a terminal to switch an antenna and the length of a symbol. According to a second embodiment of the present disclosure, a method for transmitting an SRS for antenna switching is provided by omitting the guard period when a plurality of RF Tx chains can be utilized according to specified conditions.

[0153] <First Embodiment: Method for determining guard period based on terminal capability and subcarrier spacing and SRS transmission method>

[0154] Hereinafter, according to the first embodiment, a method for determining whether a guard period is required when transmitting an SRS resource for antenna switching based on the time required to switch an antenna that the terminal can support and the SCS (subcarrier spacing), and for the terminal to transmit an SRS for antenna switching to a base station based thereon, will be described in detail.

[0155] According to one embodiment of the present disclosure, if a terminal requires switching time to switch an RF Tx chain connected to one antenna to another antenna, such switching time may be required. The switching time required for the terminal to switch antennas in this manner may be referred to as the 'antenna switching transient period'. The antenna switching transient period may vary depending on the terminal implementation and operating frequency, etc. For example, in FR1, it is approximately 15 The transient period of (or 10 A transient period) may be required. As another example, in FR2, about 5 A transient period may be required. During the transient period while the terminal is switching its antenna, it may be unable to perform UL transmission using the corresponding RF Tx chain and antenna. In other words, the terminal may not expect to transmit UL in the corresponding serving cell and frequency band during that transient period. The transients in FR1 and FR2 are predefined values ​​that can be defined as common values ​​for all terminals, determined by considering the various terminals supported by the 5G system. However, with advancements in implementation technology, if a specific terminal can switch its antenna more quickly, only a short transient period may be required. If UL transmission is scheduled not to be performed for a terminal capable of switching its antenna during such a short transient period by considering a long transient period, UL resource efficiency may be degraded. In particular, between SRS resource transmissions for antenna switching, a GP (guard period) of fixed symbol Y is inserted as defined in [Table 3] in [SRS: Antenna switching], so that the terminal does not perform UL transmission (or SRS transmission) during the GP.

[0156] According to one embodiment of the present disclosure, if the following conditions are met, a GP may not be inserted while the terminal transmits an SRS for antenna switching purposes (hereinafter, 'SRS AS' may be used interchangeably for convenience):

[0157] - If the transient period required for the terminal to switch the antenna is smaller than a certain threshold, even if the terminal fails to transmit the SRS for some time by switching the antenna within the SRS transmission symbol, it may not significantly affect the performance of the SRS-based channel estimation.

[0158] Even if the terminal does not transmit part of the SRS symbol, the uplink channel estimation accuracy may not decrease below a certain performance level depending on the base station's SRS reception performance.

[0160] According to one embodiment of the present disclosure, based on the above-described conditions, the terminal can determine whether to insert a GP between SRS resources while the terminal transmits an SRS AS according to the following methods by considering both the terminal's ability to switch antennas and the base station's SRS reception performance.

[0161] [Method 1] It is possible to determine whether the switching time, which is the time required for the terminal to switch the antenna reported as the terminal capability (UE capability), is greater than a certain ratio relative to the OFDM symbol duration for each subcarrier spacing (SCS). If the terminal's switching time is less than the specific ratio relative to the OFDM symbol duration for a specific SCS, the terminal can transmit the SRS resources of that SRS AS without a GP when transmitting the SRS AS. If the terminal's switching time is greater than the specific ratio relative to the OFDM duration for a specific SCS, the terminal may need to transmit the SRS AS by inserting a GP between the SRS resources of that SRS AS.

[0162] According to one embodiment of the present disclosure, a terminal may report terminal capability for switching time by SCS. To report terminal capability for switching time by SCS, the terminal may select one of specific candidate values ​​for each SCS and report it to the base station. Alternatively, the terminal may report terminal capability for switching time to the base station in common for all SCSs. Alternatively, the terminal may select terminal capability for switching time by frequency range (specifically FR1, FR2, or FR3) and report it to the base station. To report terminal capability for switching time for all SCSs, the terminal may select one of specific candidate values ​​and report it to the base station. Candidates for reporting terminal capability for switching time are It can be determined by unit values. For example, candidate values ​​for switching time are [0 , 5 , 10 , 15 , 20 It may be determined as or similarly as ]. For example, if the terminal reports 10 as the terminal capability for switching time for SCS 30kHz. If reported, the terminal switches the antenna between each SRS resource transmission of the SRS AS configured in the 30 kHz UL BWP for 10 This may imply that a switching time is required. Alternatively, candidates for reporting terminal capability for switching time may be determined by symbol-unit values. For example, candidate values ​​for switching time may be determined as [0, 1, 2, 3, 4, 5] or [0sym, 1sym, 2sym, 3sym, 4sym, 5sym] or similarly. For example, if a terminal reports 0sym as the terminal capability report for switching time for SCS 15 kHz, this may imply that the terminal can switch antennas without additional symbols corresponding to GP between each SRS resource transmission of the SRS AS set in the UL BWP of 15 kHz. Alternatively, candidates for reporting terminal capability for switching time may be determined by values ​​of any time-related unit. In the specific examples described above, the operation of reporting terminal capability per SCS, such as 30 kHz or 15 kHz, was explained but is not limited thereto. For example, the terminal may report to the base station terminal capabilities that are applicable to all SCSs in common or terminal capabilities per FR.

[0163] According to one embodiment of the present disclosure, a specific ratio for determining whether to insert a GP for a specific SCS may be defined as a fixed value specified in the specification. The fixed value specified in the specification may be determined as a percentage (%) representing the ratio between a symbol according to a specific SCS and a switching time reported by a terminal. Or, the fixed value specified in the specification represents the ratio between a symbol according to a certain SCS and a switching time reported by a terminal. It can be determined as follows. Specifically, if a terminal requires a switching time of 50% or more (or 1 / 2 or more) of the specification's 30kHz SCS symbol duration to switch the antenna, the terminal may need to insert a GP between the transmission of SRS resources for SRS AS. That is, the terminal... the duration of the 30kHz SCS symbol (e.g., 35.68 switching time less than 50% of ) (e.g., 17.84 Less than, as a specific example, 10 If the antenna can be switched with ), the terminal can transmit the SRS resource of the SRS AS configured in the 30kHz UL BWP without GP. If the terminal 10 to switch the antenna at the 60kHz SCS If a switching time is required, and the ratio at which the GP specified in the standard can be omitted is 50%, then the symbol duration of the 60kHz SCS (e.g., 17.84 50% of ) (e.g., 8.92 Since the switching time is greater than that, the terminal can transmit SRS resources by inserting a GP between each SRS resource transmission of the SRS AS set in the 60kHz UL BWP.

[0164] Alternatively, according to one embodiment of the present disclosure, a ratio for determining whether to insert a GP in common for all SCSs may be defined as a fixed value in the specification. A ratio for determining whether to insert a GP in common for all SCSs may be determined as a % or a ratio value, similar to how a ratio for determining whether to insert a GP for a specific SCS is defined as a fixed value in the specification, and the terminal may determine whether to insert a GP when transmitting an SRS resource of an SRS AS by checking the ratio between the symbol duration of each SCS and the switching time reported by the terminal according to the value set in common for all SCSs.

[0165] Alternatively, according to one embodiment of the present disclosure, a ratio for determining whether to insert a GP for a specific SCS may be defined as a value determined according to the implementation of the base station. This may be a value determined by the base station in relation to the performance of the SRS receiver according to the implementation of the base station. If the performance of the base station's SRS receiver is excellent such that the terminal completes antenna switching within x% based on one symbol for a certain SCS, and the SRS-based UL channel estimation accuracy can be reduced to within y% even when transmitting the SRS resource for the remaining 100-x% of one symbol and the remaining SRS resource symbols, then the terminal may transmit the SRS resource of the SRS AS without a GP for the said SCS. As a specific example, if a base station receives an SRS resource for a time interval corresponding to 100-x% (e.g., 60%) of the SRS resource transmitted for one symbol in a certain SCS (e.g., 30 kHz) and estimates the channel, the channel accuracy decreases to within y% (e.g., 10%) compared to the channel accuracy estimated by receiving the SRS for the entire symbol, the base station may not insert a separate GP for a terminal that can switch its antenna within a time interval of x% (e.g., 40%) of one symbol in a certain SCS (e.g., 30 kHz). In this case, the base station may set an SRS resource set and an SRS resource for the SRS AS for the terminal and trigger the SRS AS so that the terminal transmits the SRS AS. On the other hand, if the terminal can switch its antenna for a time interval longer than x% (e.g., 40%) of one symbol in a certain SRS (e.g., 30 kHz), the base station may insert a GP for that terminal between the transmission of the SRS resource.As a result, the base station can set an SRS resource set and an SRS resource for SRS AS on the terminal to allow the terminal time required to switch antennas, and trigger SRS AS.

[0166] According to one embodiment of the present disclosure, a ratio for determining whether to insert a GP in common to all SCSs other than a specific SCS may be defined as a value determined according to the implementation of the base station.

[0167] According to one embodiment of the present disclosure, an SRS repetition factor may also influence the decision on whether to insert a GP. For example, if the number of repetitions of an SRS resource in the time domain is greater than 1, the decision on whether to insert a GP may be made by checking the ratio between the switching time and the total SRS resource transmission time, taking this into consideration.

[0168] According to one embodiment of the present disclosure, if the terminal transmits an SRS resource by adding a GP between the switching time of the terminal and the transmission of an SRS resource for an SRS AS set in the UL BWP of a certain SCS according to the conditions described above, the length of the GP may be determined by considering the switching time of the terminal and the symbol duration of the SCS. Since the GP length is determined by the switching time reported by the terminal through terminal capability and the symbol duration of the SCS, the base station and the terminal can perform SRS AS transmission and reception operations by considering the same GP length. That is, the base station determines the GP by considering the terminal capability report regarding the switching time reported by the terminal and the symbol duration of the supported SCS, and by considering this, can set the SRS resource set of the SRS AS and the resources in the time domain of the SRS resources within the SRS resource set (start symbol, symbol length, etc. of the SRS resource) as RRC. Additionally, the terminal can transmit SRS resources within the SRS resource set for the SRS AS according to the RRC parameters set by the base station and the switching time of the terminal. For example, if the terminal transmits SRS resources by adding a GP between transmissions of SRS resources for an SRS AS configured in the UL BWP of a certain SCS, the length of the GP inserted between each SRS resource is It can be defined as. If the switching time required for the terminal to switch the antenna at a 60kHz SCS is 10 And if an SRS resource is transmitted by adding a GP between SRS resource transmissions for SRS AS, the length of the GP inserted between SRS resource transmissions of the SRS AS configured in the UL BWP of the 60kHz SCS is It can be defined by a symbol. Or, if the switching time required for the terminal to switch the antenna at 120kHz SCS is 10 And if an SRS resource is transmitted by adding a GP between SRS resource transmissions for SRS AS, the length of the GP inserted between SRS resource transmissions of the SRS AS configured in the UL BWP of the 120kHz SCS is It can be defined as a symbol.

[0169] In the present disclosure, the symbol duration for the above-described SCS refers to the time including the CP. Alternatively, the symbol duration for the above-described SCS may refer only to the time during which the SRS is transmitted excluding the CP (cyclic prefix).

[0170] According to one embodiment of the present disclosure, when a terminal transmits SRS resources for SRS AS without a separate GP, the terminal may perform an operation of switching an antenna using a portion of time preceding the transmission start symbol of a certain SRS resource, a portion of time preceding the transmission end symbol of a certain SRS resource, or a portion of time preceding the transmission start symbol of a certain SRS resource and a portion of time preceding the transmission end symbol of a certain SRS resource.

[0171] FIG. 3 illustrates examples of cases in which an SRS resource for SRS AS is transmitted without a separate GP in a wireless communication system according to one embodiment of the present disclosure.

[0172] According to one embodiment of the present disclosure, when a terminal performs an operation of switching an antenna using a portion of the start time of a transmission start symbol of an SRS resource (300), the terminal may use a portion of the start symbols assigned to the SRS (302, 303, 304) as time (306, 307, 308) for antenna switching and transmit the SRS resource during the time excluding the time used to switch the antenna among the start symbols assigned to the SRS resources (302, 303, 304) and symbols other than the assigned start symbols (meaning the case where the SRS resource is transmitted repeatedly). Since the first example (300) assumes that there is no other UL transmission or DL ​​reception before transmitting the first SRS resource (301), a transient period (305) may exist before transmitting the first SRS resource (301). Similarly, a transient period (309) may exist after transmitting the last SRS resource (304). That is, the first example (300) assumes that there is no other UL transmission or DL ​​reception after the last SRS resource (304) is transmitted, so a transient period (309) may exist after the last SRS resource (304) is transmitted.

[0173] According to one embodiment of the present disclosure, when a terminal performs the operation of switching an antenna using a portion of the last time of the last symbol of a transmission of an SRS resource (310), the terminal may use a portion of the last symbols assigned to the SRS resources (311, 312, 313) as time (316, 617, 318) for switching the antenna and transmit the SRS resource for a period excluding the time used to switch the antenna from the remaining symbols assigned to the SRS resources (meaning the case where the SRS resource is transmitted repeatedly) and the time of the last symbols assigned. Since the second example (310) assumes that there is no other UL transmission or DL ​​reception before transmitting the first SRS resource (311), a transient period (315) may exist before transmitting the first SRS resource (311). The second example (310) assumes that there is no other UL transmission or DL ​​reception after the last SRS resource (314) is transmitted, so a transient period (319) may exist after the last SRS resource (314) is transmitted.

[0174] According to one embodiment of the present disclosure, when a terminal switches antennas using both the first part of the time before the transmission start symbol of a certain SRS resource and the last part of the time before the transmission end symbol of a certain SRS resource (320), the terminal may use the last part of the time before the transmission end symbol of the SRS resource (321, 322, 323) and the first part of the time before the transmission first symbol of the SRS resource (322, 323, 324) to be transmitted next as the time (326, 327, 328) for switching antennas and transmit the SRS resource for the time excluding the time used to switch antennas among the remaining symbols assigned to the SRS resource, the assigned start symbol, and the assigned last symbol. Since the third example (320) assumes that there is no other UL transmission or DL ​​reception before transmitting the first SRS resource (321), a transient period (325) may exist before transmitting the first SRS resource (321). The third example (320) assumes that there is no other UL transmission or DL ​​reception after the last SRS resource (324) is transmitted, so a transient period (329) may exist after the last SRS resource (324) is transmitted.

[0175] [Method 2] It can be determined whether the time required for the terminal to switch the antenna, i.e., the switching time, reported by the terminal through its UE capability, is greater than a specific time value. If the terminal's switching time is less than the specific time value, the terminal can transmit the SRS resources of the SRS AS without a GP when transmitting the SRS AS. If the terminal's switching time is greater than the specific time value, the terminal may need to transmit the SRS AS by inserting a GP between the SRS resources of the SRS AS when transmitting the SRS AS.

[0176] As described in [Method 1], according to one embodiment of the present disclosure, the terminal may report terminal capability at switching time by SCS, by frequency range, or in common for all SCS and frequency ranges.

[0177] According to one embodiment of the present disclosure, a specific time value to be compared with the switching time reported by the terminal for each specific SCS, each specific FR, or all SCS and FR in common may be defined for each specific SCS, each specific FR, or in common for all SCS and FR.

[0178] For example, the base station and the terminal may define a specific time value as a cyclic prefix (CP) for a specific SCS to determine whether to insert a GP applicable to that SCS. If the switching time for a 30 kHz SCS reported by the terminal as UE capability is shorter than the CP of the 30 kHz SCS, and thus the terminal can switch the antenna within the CP time, the terminal can transmit the SRS resource of the SRS AS set in the UL BWP of the 30 kHz without a GP. On the other hand, if the switching time for a 60 kHz SCS reported by the terminal as UE capability is longer than the CP of the 60 kHz SCS, and thus the terminal cannot switch the antenna within the CP time, the terminal may need to insert a GP between the transmissions of the SRS resource of the SRS AS set in the UL BWP of the 60 kHz.

[0179] For example, the base station and the terminal may define a specific time value for determining whether to insert a GP that is applicable to all SCSs and FRs as a CP for a specific SCS. Alternatively, the base station and the terminal may define a specific time value for determining whether to insert a GP that is applicable to all SCSs and FRs as a fixed value in milliseconds.

[0180] If a GP must be inserted between the transmissions of an SRS resource of an SRS AS according to [Method 2], the length of the GP may be determined by considering the terminal capability report regarding the switching time reported by the terminal and the symbol duration of the supported SCS, similar to what was described in detail in [Method 1]. For example, the length of the GP inserted between each SRS resource is It can be defined as.

[0181] According to one embodiment of the present disclosure, when transmitting SRS resources for SRS AS without a separate GP, the terminal may perform an operation of switching the antenna using a portion of time before the transmission start symbol of a certain SRS resource, a portion of time after the transmission end symbol of a certain SRS resource, or both a portion of time before the transmission start symbol and a portion of time after the transmission end symbol of a certain SRS resource.

[0182] [Method 3] A table defining the minimum guard period between two SRS resources in an SRS resource set for antenna switching can be determined based on the time required to switch the antenna reported by the terminal as its UE capability, i.e., the switching time. If the terminal can switch the antenna with a switching time greater than a certain value (e.g., a time value in milliseconds such as T1 or a ratio value in percentage units such as R1), the symbol length of the GP inserted between the SRS resources can be defined according to the following [Table 4]. That is, if the terminal reports a switching time greater than a certain value as its UE capability, the base station determines the GP for the terminal as shown in the following [Table 4] and sets the SRS resource set and SRS resources to support SRS AS.

[0183] [Table 4]

[0185]

[0187] Here, 'some value' may be some ratio or a fixed value, as described in [Method 1] or [Method 2] above.

[0188] According to one embodiment of the present disclosure, if a terminal reports the switching time as a UE capability because it can switch the antenna with a switching time that is less than or equal to any value described above (e.g., a time value in ms such as T1 or a ratio value in % such as R1) and greater than any other value (e.g., a time value in ms such as T2 or a ratio value in % such as R2), the terminal may define the symbol length of the GP inserted between the SRS resources according to the following [Table 5]. In this case, the base station may determine the GP as in [Table 5] and set the SRS resource set and SRS resources to support SRS AS.

[0189] [Table 5]

[0190]

[0192] According to one embodiment of the present disclosure, if the terminal has some value (e.g., T n or R n n is less than or equal to any value greater than or equal to 2) and another value (e.g., T n+1 or R n+1 If the antenna can be switched with a switching time greater than ) and the switching time is reported as a UE capability, the terminal may define the symbol length of the GP inserted between SRS resources according to one of the following [Table 6], [Table 7], [Table 8], [Table 9], or [Table 10]. In this case, the base station may determine the GP as in one of [Table 6], [Table 7], [Table 8], [Table 9], or [Table 10] and set the SRS resource set and SRS resources to support SRS AS.

[0193] [Table 6]

[0194]

[0196] [Table 7]

[0197]

[0198] [Table 8]

[0199]

[0200] [Table 9]

[0201]

[0202] [Table 10]

[0203]

[0205] According to one embodiment of the present disclosure, if a terminal has reported a UE capability for a switching time applicable to all SCSs, the base station and the terminal may select one of the above-described [Table 4] to [Table 10] to determine whether to insert a GP between SRS resources of an SRS resource set for an SRS AS and the length of the GP, taking into account the UE capability reported by the terminal. Alternatively, if the terminal has reported a UE capability for a different switching time for each SCS, the base station and the terminal may select multiple of the above-described [Table 4] to [Table 10] to determine whether to insert a GP between SRS resources of an SRS resource set for an SRS AS and the length of the GP, taking into account the UE capability for each SCS reported by the terminal.

[0206] According to one embodiment of the present disclosure, a table defining the minimum guard period between two SRS resources of an SRS resource set for antenna switching may be defined according to the terminal capability regarding the switching time or capability according to the switching time, which is applied commonly to each SCS or all SCSs reported by the terminal, and the SCS supported by the base station and the terminal.

[0208] [Table 11]

[0209]

[0211] [Table 12]

[0212]

[0214] [Table 13]

[0215]

[0217] [Table 14]

[0218]

[0220] [Table 15]

[0221]

[0223] [Table 16]

[0224]

[0226] According to one embodiment of the present disclosure, in the above-described [Tables 11] through [Table 16], Capability n (where n may mean a positive number from 1 to 6) may be defined as any one capability class (or level) determined by the switching time per SCS that the terminal can support or the switching time that applies commonly to all SCSs. For example, depending on the implementation of the terminal, k0 as the switching time for a terminal to switch an antenna (For example, 15 Less than ) and k1 (e.g., 10 If more than ) time is required, the capability of the terminal can be defined as Capability 2. Similarly, k1 is the switching time for a terminal to switch its antenna. (e.g., 10 Less than ) and k2 (For example, 5 If more than ) time is required, the capability of the terminal can be defined as Capability 3. Of course, this is just one example of a terminal's capability, and each Capability n can be defined as follows.

[0227] [Table 17]

[0228]

[0230] According to one embodiment of the present disclosure, the values ​​of k0 to k5 for the required time (t) in [Table 17] may be determined according to the implementation of the base station or defined in the specifications. The terminal may report the required switching time, t (specific to SCS or common to SCS) to the base station, or report one of Capabilities 1 to 6 (specific to SCS or common to SCS) to the base station according to [Table 17] described above.

[0233] [Method 4] According to one embodiment of the present disclosure, whether or not a GP is inserted can be determined based on the time required for the terminal to switch the antenna reported as the terminal capability (UE capability), i.e., the switching time, and the combination (hereinafter, Comb) of the supported SRS. [Method 4] may be used in combination with other methods described above. Additionally, a Comb pattern may be additionally considered to determine a ratio or some value for determining whether or not a GP is inserted based on the Comb of SRS resources for antenna switching.

[0234] According to one embodiment of the present disclosure, when signals corresponding to 0 and SRS sequences are mapped from one OFDM symbol to a frequency domain resource and transmitted according to a Comb pattern, a signal that is repeatedly transmitted in the time domain is transmitted. Specifically, if 0 and SRS sequences are alternately mapped to a frequency domain subcarrier and transmitted according to a Comb 2 pattern, the corresponding time domain signal is transmitted with the same waveform repeated twice during one OFDM symbol duration. As a result, even if the base station receives only half of the signal in the time domain, the base station can estimate the downlink channel based on the uplink channel and reciprocity. Of course, since the base station receives only half of the signal transmitted twice, a loss in terms of received power may occur. Consequently, the accuracy of channel estimation may be reduced. However, if the reception performance of the base station is excellent, the degradation of channel estimation accuracy may be minimal or very small.

[0235] According to one embodiment of the present disclosure, if 0 and SRS sequences are transmitted in a 3:1 ratio according to a Comb 4 pattern, the signal in the time domain can be transmitted with the same waveform repeated four times during one OFDM symbol duration. In the case of following the Comb 4 pattern, since the same waveform must be repeated four times during the same OFDM symbol duration, the duration of one waveform can be halved compared to the Comb 2 pattern. However, similar to the case of the Comb 2 pattern, if the reception performance of the base station is relatively good, even if the base station receives only one of the four repeated waveforms (or a positive number less than 4, i.e., one, two, or three times), the base station can estimate the downlink channel based on the uplink channel and reciprocity. Therefore, according to the Comb set for the SRS for antenna switching, even if the terminal switches the antenna for 50% or 75% of the time based on a certain SCS, if the terminal can successfully transmit the SRS for the remaining 50% or 25% of the time, the terminal may transmit the SRS resource without a separate GP. This can be determined by the switching time required for the terminal to switch the antenna, based on the base station's reception performance, the RRC parameters set by the base station on the terminal, and the terminal's capabilities.

[0236] According to one embodiment of the present disclosure, if an SRS resource for SRS AS is transmitted without a GP according to [Method 1] to [Method 4] as described above, the base station may set RRC parameters to allow the SRS resource within the SRS resource set for SRS AS to be transmitted without a GP to the terminal. For example, two adjacent SRS resources may be configured so that the difference between the startPosition (e.g., 3 and 1) set in each SRS resource is equal to nrofSymbols (e.g., 2), allowing them to be transmitted continuously without a separate GP.

[0237] According to one embodiment of the present disclosure, if an SRS resource for SRS AS is transmitted with consideration of a GP according to [Method 1], the base station may set RRC parameters so that an SRS resource within an SRS resource set for SRS AS can be transmitted to a terminal with consideration of a GP determined according to the method described in [Method 1] through [Method 4]. For example, two adjacent SRS resources may be configured such that the difference between the startPosition (e.g., 3 and 1) set in each SRS resource is equal to the sum of nrofSymbols (e.g., 1) and a GP (e.g., 1), allowing a GP of 1 symbol to be inserted between the transmission of the two SRS resources.

[0238] According to one embodiment of the present disclosure, if the guard period of the Y symbol is not set in the terminal according to [Method 1] to [Method 4] as described above, the terminal can continuously transmit one set of SRS resources (i.e., the terminal can transmit two SRS resources within the same set of SRS resources without a gap of the Y symbol).

[0239] According to one embodiment of the present disclosure, if the guard period of the Y symbol is not set according to [Method 1] through [Method 4] as described above, the terminal may transmit SRS resources of different SRS resource sets for adjacent antenna switching purposes in succession (i.e., the terminal may transmit two SRS resources within different SRS resource sets without a gap of the Y symbol). As described above, the guard period of the Y symbol may be explicitly set through a separate new RRC parameter (e.g., a parameter to indicate that the guard period is not set for the SRS resource set for antenna switching purposes within the SRS-Config). Alternatively, the guard period of the Y symbol may be implicitly set through the SRS resource setting according to the UE capability reported by the terminal and the implementation capability of the base station.

[0240] <Second Embodiment: Efficient SRS transmission method based on temporary RF Tx chain availability>

[0241] According to the second embodiment of the present disclosure, a method for transmitting an SRS resource for antenna switching without a separate GP when a terminal composed of a plurality of PAs to support CA, etc. satisfies specific conditions is described in detail.

[0242] According to one embodiment of the present disclosure, a plurality of PAs for supporting UL transmission may be configured in a terminal depending on the implementation details of the terminal. For example, a terminal may include two PAs capable of UL transmission.

[0243] According to one embodiment of the present disclosure, a terminal comprising two PAs can support 2Tx by connecting the two PAs to different antennas. In this case, the terminal can support 2Tx on the same carrier component. Alternatively, by supporting Tx for each of two different carrier components (which may be intra-band or inter-band depending on the characteristics of the PA), the terminal may support carrier aggregation of two carrier components operating as 1Tx.

[0244] According to one embodiment of the present disclosure, when a terminal performs a terminal capability report after first connecting to a base station, the terminal may report to the base station information that the terminal can support up to 2Tx. For example, when the terminal reports terminal capability for a specific band to the base station, the terminal may report to the base station a capability that it can support antenna switching of 2TYR (wherein Y may be defined as a positive integer greater than or equal to 2. Additionally, Y may be defined as 2, 4, 6, 8, or a specific number greater than 2 added in a 6G system). Specifically, the terminal may report to the base station by setting at least one of the bits corresponding to t2r2, t2r6, t2r6, and t2r8, which signify 2Tx-based antenna switching operation among the RRC parameters for terminal capability reporting called srs-AntennaSwitchingBeyond4RX, to 1. More specifically, the 11 bits of the parameter srs-AntennaSwitchingBeyond4RX for reporting terminal capability may indicate whether antenna switching can be supported for t1r1, t2r2, t1r2, t4r4, t2r4, t1r4, t2r6, t1r6, t4r8, t2r8, and t1r8 in order. For example, the terminal may report to the base station by setting the 11 bits as 01001010010.

[0245] According to one embodiment of the present disclosure, when the terminal reports terminal capability for the same band and terminal capability for a band combination including the same band, the terminal may report to the base station that it can support 1Tx to further support the above-described 1Tx-based CA. For example, when the terminal reports terminal capability for a specific band, the terminal may further report to the base station a capability to support antenna switching of 1TWR (wherein W may be defined as a positive integer greater than or equal to 1. Additionally, W may be defined as a specific number greater than 1 added in 1, 2, 4, 6, 8, 6G systems). Specifically, the terminal may report to the base station by setting the 11 bits for srs-AntennaSwitchingBeyond4RX as 11101111011. As a result, the base station can understand that the terminal can transmit an SRS for antenna switching purposes using 1Tx and 2Tx.

[0246] According to one embodiment of the present disclosure, if a base station can set up and support a UL CA in which two carrier components based on 1Tx are aggregated for a terminal having the capability described above, the base station can set up an SRS resource set for the terminal to support antenna switching of 1TWR (e.g., 1T4R).

[0247] According to one embodiment of the present disclosure, if a terminal transmits an SRS resource set to support antenna switching of 1TWR (e.g., 1T4R) for one carrier component (e.g., CC1) and simultaneously another UL transmission (e.g., PUSCH) is scheduled for another carrier component (e.g., CC2) among the two carrier components of the UL CA, the terminal may simultaneously transmit the SRS resource set for antenna switching scheduled for one carrier component (CC1) and the PUSCH scheduled for the other carrier component (CC2) using different 1Tx (wherein the terminal may require the capability to simultaneously transmit SRS and PUSCH to different CCs).

[0248] According to one embodiment of the present disclosure, if a terminal transmits an SRS resource set to support antenna switching of 1TWR (e.g., 1T4R) for one carrier component (e.g., CC1), and at the same time, no other UL transmission is scheduled for another carrier component (e.g., CC2) among the two carrier components of the UL CA, the terminal may transmit an SRS resource set for antenna switching scheduled for one carrier component (CC1) using 2Tx. In this case, the terminal may transmit the SRS for antenna switching without a GP or by inserting a small number of GPs through the following Option 1 and Option 2.

[0249] - Option 1: While the terminal is transmitting an SRS resource configured in an SRS resource set for antenna switching using 1Tx, the terminal may prepare to transmit the next SRS resource by switching the Tx of another carrier component to the antenna that is not transmitting the SRS resource for antenna switching. This may be a method of temporarily using a Tx for another component carrier of a UL CA that is not transmitting other UL signals, including SRS, to transmit the SRS for antenna switching. Since the terminal switches the antenna connected to another Tx while transmitting an SRS resource using one Tx, the terminal may transmit the next SRS resource without a separate GP. To support a method like Option 1, the terminal may need to support additional terminal capabilities to temporarily borrow a Tx connected to another CC that supports UL CA to switch the antenna and transmit the SRS.

[0250] FIG. 4 illustrates an example of a method for transmitting an SRS resource for antenna switching without a GP by borrowing a Tx connected to another CC in a wireless communication system according to one embodiment of the present disclosure.

[0251] According to one embodiment of the present disclosure, a terminal can transmit a UL signal to CC1 using a first Tx (411) and transmit a UL signal to CC2 using a second Tx (412). If UL transmission is not scheduled to CC2 and the second Tx (412) is not used in CC2, and an SRS resource set for 1T4R antenna switching is triggered in CC1 of the terminal, and the terminal needs to transmit a 1-port SRS through four antennas, the terminal can use the second Tx (412) in CC1. Therefore, it can be understood that all SRS resources (421, 422, 423, 424) are transmitted to CC1, even if some of the SRS resources (422, 424) are transmitted using the second Tx (412).

[0252] According to one embodiment of the present disclosure, the terminal can transmit SRS resource1 (421) to the first antenna (401) connected to the first Tx (411).

[0253] According to one embodiment of the present disclosure, while the terminal transmits SRS resource1 (421) to the first Tx (411), the terminal may connect the second Tx (412) connected to CC2 to the second antenna (402). At this time, the terminal may connect the second Tx (412) to the second antenna (402) and not transmit any UL signal.

[0254] According to one embodiment of the present disclosure, after the terminal transmits SRS resource1 (421), the terminal can transmit SRS resource2 (422) to a second antenna (402) connected to a second Tx (412).

[0255] According to one embodiment of the present disclosure, while the terminal transmits SRS resource2 (422) to the second Tx (412), the terminal may connect the first Tx (411) connected to the first antenna (401) to the third antenna (403). Likewise, the terminal may connect the first Tx (411) to the third antenna (403) and not transmit any UL signal.

[0256] According to one embodiment of the present disclosure, after the terminal transmits SRS resource 2 (422), the terminal can transmit SRS resource 3 (423) to a third antenna (403) connected to the first Tx (411).

[0257] According to one embodiment of the present disclosure, while the terminal transmits SRS resource3 (423) to the first Tx (411), the terminal may connect the second Tx (412), which is connected to the second antenna (402), to the fourth antenna (404). Likewise, the terminal may connect the second Tx (412) to the fourth antenna (404) and not transmit any UL signal.

[0258] According to one embodiment of the present disclosure, after the terminal transmits SRS resource 3 (423), the terminal can transmit SRS resource 4 (424) to a fourth antenna (404) connected to a second Tx (412).

[0259] As illustrated in FIG. 4, while a terminal is transmitting one SRS resource, the terminal may complete preparations in advance to transmit the next SRS resource by switching another Tx (or which may be defined as a Tx RF chain, etc.) to a different antenna. The example in FIG. 4 is merely one embodiment and is not limited thereto. For example, the terminal may transmit SRS resources by connecting each Tx to a single antenna according to the terminal implementation. In this case, the terminal may need to transmit SRS resources by transmitting different SRS resources through different antennas so that SRS can be transmitted through all antennas.

[0260] According to one embodiment of the present disclosure, a base station may set to a terminal both an SRS resource set for antenna switching that includes an SRS resource with RRC parameters set considering an inserted GP, and an SRS resource set for antenna switching that includes an SRS resource with RRC parameters set with the GP omitted. Additionally, the base station may schedule the terminal considering the scheduling situation of the UL CA (e.g., whether UL is transmitted via CC2 as in the example described above). For example, the base station may schedule the terminal to transmit an SRS for antenna switching at CC1 by triggering one of the two SRS resource sets.

[0261] According to one embodiment of the present disclosure, a base station may set to a terminal only one of an SRS resource set for antenna switching that includes an SRS resource with RRC parameters set considering an inserted GP, and an SRS resource set for antenna switching that includes an SRS resource with RRC parameters set with the GP omitted. The terminal may perform SRS resource transmission considering the set SRS resource set for antenna switching and the scheduling situation of UL CA. For example, considering the set SRS resource set for antenna switching and the scheduling situation of UL CA, the terminal may transmit an SRS resource by omitting the GP or transmit an SRS resource by inserting the GP.

[0262] According to one embodiment of the present disclosure, RRC parameters for an SRS resource may include both resource settings in a time domain where a GP is added and resource settings in a time domain where a GP is omitted.

[0263] - Option 2: The terminal may support 2Tx-based antenna switching by additionally utilizing a Tx from another CC that does not perform UL transmission. According to the above-described Option 1, when the terminal transmits a single SRS resource, the terminal uses only 1Tx, and the terminal may omit the GP by switching the other Tx to a different antenna in advance. On the other hand, according to Option 2, the terminal may transmit the SRS resource by utilizing both 2Tx. Consequently, after the terminal transmits the SRS resource transmitted via 2Tx, switching time may be required for the terminal to switch the 2Tx to a different antenna. In this case, considering the method described in the first embodiment, a GP may need to be inserted during the transmission of the SRS resource. To support a method such as Option 2, the terminal may need to support additional terminal capabilities to temporarily borrow a Tx connected to another CC that supports UL CA to switch the antenna and transmit the SRS.

[0264] According to one embodiment of the present disclosure, when a terminal switches antennas by temporarily borrowing a Tx connected to another CC that supports UL CA through a method such as Option 2 described above, the terminal may expect that the terminal will not perform any UL transmissions for a specific time prior to transmitting the first transmitted SRS resource. In this case, the base station may not schedule any UL transmissions to the terminal during that time. Alternatively, a UL channel that can be transmitted without a separate switching time using only one connected Tx (or some Tx) may be scheduled. To this end, it may be required for the base station and the terminal to accurately identify the number of available Tx. The base station and the terminal may identify the connection status of the current Tx by considering the number of ports of the UL channel transmitted at a previous time point, etc. Here, the specific time may be defined as the time required for a terminal supporting UL Tx switching to perform UL Tx switching or a new time. In this case, the terminal may report its terminal capability for the time required to the base station. For example, a terminal that supports UL Tx switching may report values ​​such as uplinkTxSwitchingPeriod, uplinkTxSwitchingPeriod2T2T, or uplinkTxSwitchingPeriodForBandPair, which represent the time required to perform UL Tx switching, to the base station through terminal capability reporting. Alternatively, the terminal may report to the base station the time required for the terminal to temporarily borrow a Tx connected to another CC using parameters for new terminal capability reporting.

[0265] FIG. 5 illustrates an example of a method for transmitting an SRS resource for antenna switching purposes by borrowing a Tx connected to another CC in a wireless communication system according to one embodiment of the present disclosure and adding a reduced number of GPs.

[0266] According to one embodiment of the present disclosure, a terminal can transmit a UL signal to CC1 using a first Tx (511) and transmit a UL signal to CC2 using a second Tx (512). If UL transmission is not scheduled to CC2 and the second Tx (512) is not used in CC2, and an SRS resource set for antenna switching for four receiving antennas is triggered in CC1 of the terminal, and the terminal needs to transmit SRS through four antennas, the terminal can use the second Tx (512) in CC1. Hereinafter, it is understood that the SRS resource (521, 522) is transmitted to CC1 using both Tx (511, 512).

[0267] According to one embodiment of the present disclosure, the terminal can transmit SRS resource1 (521) to a first antenna (501) connected to a first Tx (511) and a second antenna (502) connected to a second Tx (512).

[0268] According to one embodiment of the present disclosure, after a terminal transmits an SRS resource 1 (521) transmitted through two antennas (501, 502) using two Tx (511, 512), the terminal may switch antennas to transmit an SRS resource using the next antenna. At this time, the terminal may not transmit any UL signal during a GP (530, guard period).

[0269] According to one embodiment of the present disclosure, the terminal can switch two Tx (511, 512) during GP (530) to connect to the third antenna (503) and the fourth antenna (504), respectively. After antenna switching, the terminal can transmit SRS resource2 (522) to the third antenna (503) connected to the first Tx (511) and the fourth antenna (504) connected to the second Tx (512).

[0270] As illustrated in FIG. 5, the terminal may temporarily borrow the Tx of another CC to transmit an SRS resource of another CC through multiple Txes. The example in FIG. 5 is merely one embodiment and is not limited thereto. For example, the terminal may transmit an SRS resource by connecting each Tx to any two antennas according to the terminal implementation. In this case, the terminal may need to transmit the SRS resource by transmitting different SRS resources through two different antennas so that the SRS can be transmitted through all antennas.

[0271] According to one embodiment of the present disclosure, a base station may set both an SRS resource set for antenna switching, including SRS resources transmitted via 1Tx, and an SRS resource set for antenna switching, including SRS resources transmitted via 2Tx, to a terminal. Then, considering the scheduling status of the UL CA (whether UL is transmitted to CC2 as in the example above), one of the two SRS resource sets may be triggered to schedule the terminal to transmit SRS for antenna switching at CC1.

[0272] According to one embodiment of the present disclosure, a base station may set only an SRS resource set for antenna switching to a terminal, which includes SRS resources transmitted in 1Tx. The terminal may transmit the SRS resources transmitted in 1Tx, or transmit the first part of the SRS resources in 2Tx and not transmit subsequent SRS resources, taking into account the set SRS resource set for antenna switching and the scheduling situation of the UL CA.

[0273] According to one embodiment of the present disclosure, RRC parameters for an SRS resource may include both settings for when transmitted as 1Tx and settings for when transmitted as 2Tx.

[0274] The above-described Options 1 and 2 can be understood as examples assuming that the number of Tx for each CC is 1. However, embodiments according to Options 1 and 2 of the present disclosure are not limited to such assumptions. For example, the number of Tx for each CC may be generalized and extended to apply to cases where a Tx is used for CC A, b Tx for CC B, and a+b Tx are used for antenna switching.

[0275] According to one embodiment of the present disclosure, as described in the first and second embodiments, if a terminal transmits an SRS resource by omitting a GP or adding a reduced number of GPs, and a base station schedules the SRS resources of an SRS resource set using a new TDRA field for scheduling time domain resources of SRS within the DCI, the base station may schedule the entire time resources to the terminal by considering whether to insert a GP and the number of GPs to be added according to the method described above. For example, the base station schedules time resources for an SRS resource set for antenna switching purposes consisting of four SRS resources transmitted with one symbol, and if the terminal can transmit all SRS resources without a GP, the base station may schedule four symbols as time domain resources of SRS resources to the terminal through the TDRA field within the DCI. If a base station schedules time resources for an antenna switching SRS resource set consisting of four SRS resources transmitted by one symbol, and needs to insert a GP consisting of one symbol between each SRS resource transmission, the base station can schedule 4+3 symbols as time domain resources of SRS resources to the terminal through the TDRA field in the DCI.

[0277] FIG. 6 illustrates the structure of a terminal in a wireless communication system according to one embodiment of the present disclosure.

[0278] Referring to FIG. 6, the terminal may include a transceiver (referring to a terminal receiver (6-00) and a terminal transmitter (6-10)), a memory (not shown), and a terminal processing unit (6-05, or a terminal control unit or processor). Depending on the communication method of the terminal described above, the transceiver (6-00, 6-10), memory, and terminal processing unit (6-05) 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 components or fewer components than the components described above. Furthermore, the transceiver, memory, and processor may be implemented in the form of a single chip.

[0279] The transceiver can transmit and receive signals with a base station. Here, the signal may include control information and data. To this end, the transceiver may be composed of an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies a received signal and down-converts its frequency. However, this is merely one embodiment of the transceiver, and the components of the transceiver are not limited to an RF transmitter and an RF receiver.

[0280] In addition, the transceiver can receive a signal through a wireless channel and output it to a processor, and transmit the signal output from the processor through a wireless channel.

[0281] Memory can store programs and data necessary for the operation of the terminal. Additionally, memory can store control information or data included in signals transmitted and received by the terminal. Memory may be composed of storage media or combinations of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD. Additionally, there may be multiple memories.

[0282] In addition, the processor can control a series of processes to enable the terminal to operate according to the aforementioned embodiment. For example, the processor can receive a DCI composed of two layers and control the components of the terminal to receive multiple PDSCHs simultaneously. There may be multiple processors, and the processors can perform the operation of controlling the components of the terminal by executing a program stored in memory.

[0283] FIG. 7 illustrates the structure of a base station in a wireless communication system according to one embodiment of the present disclosure.

[0284] Referring to FIG. 7, the base station may include a transceiver unit, which refers to a base station receiver (7-00) and a base station transmitter (7-10), a memory (not shown), and a base station processing unit (7-05, or a base station control unit or processor). Depending on the communication method of the base station described above, the transceiver unit (7-00, 7-10), the memory, and the base station processing unit (7-05) 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 components or fewer components than the components described above. Furthermore, the transceiver unit, the memory, and the processor may be implemented in the form of a single chip.

[0285] The transceiver can transmit and receive signals with a terminal. Here, the signal may include control information and data. To this end, the transceiver may be composed of an RF transmitter that up-converts and amplifies the frequency of a transmitted signal, and an RF receiver that low-noise amplifies a received signal and down-converts its frequency. However, this is merely one embodiment of the transceiver, and the components of the transceiver are not limited to an RF transmitter and an RF receiver.

[0286] In addition, the transceiver receives a signal through a wireless channel and outputs it to a processor, and can transmit the signal output from the processor through a wireless channel.

[0287] Memory can store programs and data necessary for the operation of the base station. Additionally, memory can store control information or data included in signals transmitted and received by the base station. Memory can be composed of storage media or combinations of storage media such as ROM, RAM, hard disk, CD-ROM, and DVD. Additionally, there may be multiple memories.

[0288] A processor can control a series of processes to enable a base station to operate according to the embodiments of the present disclosure described above. For example, the processor can control each component of the base station to configure two layers of DCIs containing allocation information for a plurality of PDSCHs and to transmit them. There may be multiple processors, and the processors can perform control operations on the components of the base station by executing a program stored in memory.

[0289] 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.

[0290] When implemented in software, a computer-readable storage medium may be provided for storing one or more programs (software modules). One or more programs stored in the computer-readable storage medium are configured for execution by one or more processors within an electronic device. 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 this disclosure.

[0291] Such programs (software modules, software) may be stored in random access memory, non-volatile memory including flash memory, ROM (Read Only Memory), Electrically Erasable Programmable Read Only Memory (EEPROM), magnetic disc storage devices, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or other forms of optical storage devices, magnetic cassettes. Alternatively, they may be stored in memory composed of some or all of these. Additionally, each constituent memory may include multiple units.

[0292] Additionally, the program may be stored on an attachable storage device accessible via a communication network such as the Internet, Intranet, Local Area Network (LAN), Wide LAN (WLAN), or Storage Area Network (SAN), or a combination thereof. Such a storage device may be connected to the device performing the embodiment of the present disclosure through an external port. Additionally, a separate storage device on the communication network may be connected to the device performing the embodiment of the present disclosure.

[0293] In the specific embodiments of the present disclosure described above, the components included in the invention are expressed in a singular or plural form according to the specific embodiments presented. However, the singular or plural expression is selected to suit the situation presented for convenience of explanation, and the present disclosure is not limited to singular or plural components; even if a component is expressed in the plural form, it may be composed of a singular form, or even if a component is expressed in the singular form, it may be composed of a plural form.

[0294] Meanwhile, the embodiments of the present disclosure disclosed in this specification and drawings are merely specific examples provided to facilitate the explanation of the technical content of the present disclosure and to aid in understanding the present disclosure, and are not intended to limit the scope of the present disclosure. That is, it is obvious to those skilled in the art that other variations based on the technical concept of the present disclosure are possible. Furthermore, each of the above embodiments may be combined and operated as needed. For example, parts of one embodiment of the present disclosure and parts of another embodiment may be combined to operate a base station and a terminal. For example, parts of the first embodiment and the second embodiment of the present disclosure may be combined to operate a base station and a terminal. In addition, although the above embodiments are presented based on an FDD LTE system, other variations based on the technical concept of the above embodiments may be implemented in other systems such as a TDD LTE system, 5G, or NR system.

[0295] Meanwhile, the order of description in the drawings illustrating the method of the present invention does not necessarily correspond to the order of execution, and the order of execution may be changed or executed in parallel.

[0296] Alternatively, drawings describing the method of the present invention may omit some components and include only some components to the extent that the essence of the present invention is not compromised.

[0297] 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 impair the essence of the invention.

[0298] 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 understand that modifications can be easily made to other specific forms without altering the technical spirit or essential features of the present disclosure. The scope of the present disclosure is defined by the claims set forth below rather than by the foregoing detailed description, and all modifications or variations derived from the meaning and scope of the claims and their equivalents should be interpreted as being included within the scope of the present disclosure.

Claims

Claim 1 A control signal processing method in a wireless communication system, characterized by comprising: a step of receiving a first control signal transmitted from a base station; a step of processing the received first control signal; and a step of transmitting a second control signal generated based on the processing to the base station.

Images