Method and apparatus for srs antenna switching in a wireless communication system

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate, and provides a method for transmitting a sounding reference signal (SRS) in a wireless communication system. The method can include the steps of receiving configuration information for the SRS, the configuration information including first information indicating a number of antenna ports for the SRS; when the first information indicates 3 as the number of antenna ports, determining one antenna port through which the SRS will not be transmitted from among four antenna ports for the SRS; and transmitting the SRS to a base station based on three antenna ports other than the one antenna port.

Description

Technical Field

[0001] This disclosure relates to a method and apparatus for SRS antenna switching in a wireless communication system. Background Technology

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services. It can be implemented not only in "below 6 GHz" bands such as 3.5 GHz, but also in "above 6 GHz" bands, including 28 GHz and 39 GHz, known as mmWave. Furthermore, 6G mobile communication technology (referred to as "super 5G systems") is being considered in terahertz bands (e.g., the 95 GHz to 3 THz band) to achieve transmission rates fifty times faster than 5G and ultra-low latency one-tenth that of 5G.

[0003] At the outset of 5G mobile communication technology development, standardization was underway regarding beamforming and massive MIMO to support services and meet performance requirements associated with enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC). This standardization aimed to mitigate radio wave path loss in millimeter waves and increase radio wave transmission distance; support parameter sets for dynamic operation (e.g., operating multiple subcarrier spacings) to efficiently utilize millimeter wave resources and time slot formats; initial access technologies to support multi-beam transmission and broadband; the definition and operation of bandwidth portions (BWP); new channel decoding methods (such as low-density parity-check (LDPC) codes for large data transmissions and polar codes for highly reliable transmission of control information); L2 preprocessing; and network slicing for providing dedicated networks for specific services.

[0004] Currently, given the services supported by 5G mobile communication technology, discussions are underway regarding improvements and performance enhancements to the initial 5G mobile communication technology. Physical layer standardization for technologies such as Vehicle-to-Everything (V2X) is also in place, designed to assist autonomous vehicle driving decisions based on information about the vehicle's location and status transmitted by the vehicle, and to enhance user convenience. This includes NR-U (New Radio Unlicensed) and NR UE Energy Saving (NTN), which are UE-satellite direct communication technologies used to provide coverage and positioning in areas where communication with terrestrial networks is unavailable.

[0005] Furthermore, standardization is ongoing for technologies within the air interface architecture / protocol, such as the Industrial Internet of Things (IIoT) for supporting new services through interoperability and convergence with other industries, Integrated Access and Backhaul (IAB) for providing nodes for network service area extension by supporting wireless backhaul and access links in an integrated manner, mobility enhancements including conditional handover and Dual Active Protocol Stack (DAPS) handover, and two-step random access (two-step RACH for NR) for simplifying the random access process. Standardization is also underway for 5G baseline architectures (e.g., service-based architectures or service-based interfaces) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, as well as system architectures / services for Mobile Edge Computing (MEC) based on UE location reception services.

[0006] With the commercialization of 5G mobile communication systems, the already exponentially growing number of connected devices will be connected to the communication network, thus necessitating enhanced functionality and performance of 5G mobile communication systems as well as integrated operation of connected devices. To this end, new research related to extended reality (XR) has been arranged to effectively support augmented reality (AR), virtual reality (VR), mixed reality (MR), etc., by leveraging artificial intelligence (AI) and machine learning (ML), AI service support, metaspace service support, and drone communication to improve 5G performance and reduce complexity.

[0007] Furthermore, this development of 5G mobile communication systems will not only serve as the foundation for developing new waveforms for providing terahertz band coverage in 6G mobile communication technologies, such as multi-antenna transmission technologies like full-dimensional MIMO (FD-MIMO), array antennas, and massive MIMO; metamaterial-based lenses and antennas for improving terahertz band signal coverage; high-dimensional spatial multiplexing technologies using orbital angular momentum (OAM); and reconfigurable smart surfaces (RIS); it will also serve as the foundation for developing full-duplex technologies to improve the frequency efficiency of 6G mobile communication technologies and enhance system networks; AI-based communication technologies to achieve system optimization by leveraging satellites and AI from the design phase and internalizing end-to-end AI support functions; and next-generation distributed computing technologies to achieve services with complexity levels exceeding the operational capabilities of UEs by utilizing ultra-high-performance communication and computing resources. Summary of the Invention

[0008] Technical issues

[0009] Combining the configuration related to SRS resources (sets) and SRS antenna ports, a maximum of four antenna ports are considered for BS and UE operations. Specifically, the operation of SRS resources or SRS resource sets can be configured in the RRC configuration of the BS and UE using parameters based on the number of antenna ports.

[0010] This design approach does not consider electronic devices supporting three transmit antenna ports. Furthermore, the SRS antenna port switching operation considered across a maximum of four antenna ports is not optimized for SRS resource configuration for three transmit antenna ports, and therefore exhibits limited performance when performing downlink channel estimation.

[0011] To overcome this degradation, three uplink transmit (Tx) antenna ports will be discussed in rel-19. Specifically, for electronic devices supporting 3 Tx, a method is required for the BS to configure SRS resources and / or SRS resource sets. Therefore, through embodiments of this disclosure, a method is proposed for configuring SRS resources and / or SRS resource sets to support three uplink transmit (Tx) antenna ports. Furthermore, various embodiments of this disclosure propose parameters that need to be added or extended during the BS's SRS resource configuration process.

[0012] Technical solution

[0013] According to embodiments of this disclosure, a method performed by a terminal in a wireless communication system may include: receiving configuration information for a sounding reference signal (SRS) from a base station (BS), the configuration information including first information indicating the number of antenna ports for the SRS; when the first information indicates 3 as the number of antenna ports, determining one of the four antenna ports used for the SRS that will not transmit the SRS through; and transmitting the SRS to the BS based on the three antenna ports other than the one antenna port.

[0014] According to another embodiment of this disclosure, a method performed by a base station (BS) in a wireless communication system may include: sending configuration information for a sounding reference signal (SRS) to a terminal, the configuration information including first information indicating the number of antenna ports for the SRS; and receiving the SRS from the terminal, wherein when the first information indicates 3 as the number of antenna ports, the SRS is received based on three of the four antenna ports used for the SRS, excluding the one antenna port through which the SRS will not be transmitted.

[0015] According to another embodiment of this disclosure, a terminal in a wireless communication system may include a transceiver and a controller functionally connected to the transceiver. The controller may be configured to receive configuration information for a sounding reference signal (SRS) from a base station (BS), the configuration information including first information indicating the number of antenna ports for the SRS; when the first information indicates 3 as the number of antenna ports, determining one of the four antenna ports used for the SRS that will not transmit the SRS through; and transmitting the SRS to the BS based on the three antenna ports other than the one antenna port.

[0016] Beneficial effects

[0017] According to embodiments of this disclosure, SRS resources and / or SRS resource sets can be configured to support three uplink transmit (Tx) antenna ports.

[0018] Furthermore, according to embodiments of this disclosure, an electronic device having multiple receiving antennas (e.g., 8, 12, 24, etc.) can transmit SRS through three or more Tx antenna ports based on antenna switching.

[0019] Furthermore, according to embodiments of this disclosure, the protection period between SRS resources can be configured based on various subcarrier spacings supported in frequency bands of 6 GHz or higher. Attached Figure Description

[0020] Figure 1 The basic structure of the time-frequency domain in a wireless communication system according to an embodiment of the present disclosure is shown.

[0021] Figure 2 The frame, subframe, and time slot structure in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0022] Figure 3 An example of bandwidth configuration in a wireless communication system according to an embodiment of the present disclosure is shown.

[0023] Figure 4 An example of the configuration of the control resource set of the downlink control channel in a wireless communication system according to an embodiment of the present disclosure is shown.

[0024] Figure 5a This is a diagram illustrating the structure of a downlink control channel in a wireless communication system according to an embodiment of the present disclosure.

[0025] Figure 5b This is a diagram illustrating a scenario in a wireless communication system according to an embodiment of the present disclosure where a UE can have multiple PDCCH monitoring locations across a time slot span.

[0026] Figure 6a An example of SRS resource configuration and transmit (Tx) / receive (Rx) antenna port mapping in SRS antenna switching considering 3T4R according to an embodiment of the present disclosure is shown.

[0027] Figure 6b Another example of an antenna port configured in an SRS resource in consideration of 3T4R SRS antenna switching is shown in accordance with the description of embodiments of the present disclosure.

[0028] Figure 6cAnother example of an antenna port configured in an SRS resource in SRS antenna switching considering 3T4R is shown according to an embodiment of the present disclosure.

[0029] Figure 7a An example of SRS resource configuration for SRS antenna switching and Tx / Rx antenna port mapping in SRS antenna switching considering 3T4R is shown according to an embodiment of the present disclosure.

[0030] Figure 7b Another example of an antenna port configured in an SRS resource in consideration of 3T4R SRS antenna switching is shown in accordance with the description of embodiments of the present disclosure.

[0031] Figure 8 Another example of an antenna port configured in an SRS resource during carrier aggregation operation in an SRS antenna switching operation taking into account 3T4R is shown according to an embodiment of the present disclosure.

[0032] Figure 9 Examples of SRS resource configuration and Tx / Rx antenna port mapping in SRS antenna switching considering 3T6R according to embodiments of the present disclosure are shown.

[0033] Figure 10 Examples of SRS resource configuration and Tx / Rx antenna port mapping in SRS antenna switching considering 3T8R are shown according to embodiments of the present disclosure.

[0034] Figure 11 An example of a signaling procedure between an electronic device and a BS according to an embodiment of this disclosure is shown.

[0035] Figure 12 This is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0036] Figure 13 This is a diagram illustrating the structure of a BS in a wireless communication system according to an embodiment of the present disclosure. Detailed Implementation

[0037] Embodiments of this disclosure are described in detail below with reference to the accompanying drawings.

[0038] In describing the embodiments, detailed descriptions of technical matters well-known in the art to which this disclosure pertains and not directly related to this disclosure will be omitted. This is to convey the subject matter of this disclosure more clearly without obscuring it by omitting unnecessary descriptions.

[0039] For the same reason, some elements have been exaggerated, omitted, or simplified in the accompanying drawings. Furthermore, the size of each element does not perfectly reflect its actual size. In each drawing, identical or equivalent elements are given the same reference numerals.

[0040] The advantages and features of this disclosure, as well as the ways in which they are implemented, will become apparent from the embodiments described in detail below with reference to the accompanying drawings. However, this disclosure is not limited to the embodiments set forth below, but can be implemented in various different forms. The following embodiments are provided only to fully disclose this disclosure and to inform those skilled in the art of its scope, and this disclosure is defined only by the scope of the appended claims. Throughout the specification, the same reference numerals denote the same elements. Furthermore, in describing this disclosure, detailed descriptions of relevant functions or configurations will be omitted where it is determined that such detailed descriptions would unnecessarily obscure the subject matter of the disclosure. The terminology described below is defined in consideration of the functions in this disclosure and may vary depending on the intent or habit of the user or operator. Therefore, the definition of the terminology should be based on the entire contents of this specification.

[0041] In the following description, a base station is an entity that allocates resources to a terminal and can be at least one of a gNode B, gNB, eNodeB, Node B, base station (BS), radio access unit, base station controller, or node on a network. A terminal may include a user equipment (UE), mobile station (MS), cellular phone, smartphone, computer, or multimedia system capable of performing communication functions. In this disclosure, "downlink (DL)" refers to the radio transmission path through which a base station transmits signals to a terminal, and "uplink (UL)" refers to the radio transmission path through which a terminal transmits signals to a base station.

[0042] Furthermore, although 5G systems are described as examples in the embodiments of this disclosure below, embodiments of this disclosure can be applied to other communication systems with similar technical backgrounds or channel configurations. For example, mobile communication technologies developed after LTE or LTE-A mobile communications and 5G (6G) may be included therein. Therefore, embodiments of this disclosure can be applied to other communication systems with some modifications without departing from the scope of this disclosure, as determined by those skilled in the art. The content of this disclosure can be applied to both FDD and TDD systems.

[0043] At this point, it will be understood that each box in a flowchart, and combinations of boxes in a flowchart, can be implemented using computer program instructions. These computer program instructions can be loaded onto the processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for performing the functions specified in the flowchart boxes. These computer program instructions can also be stored in a computer-usable or computer-readable storage medium that can instruct the computer or other programmable data processing apparatus to implement the functions in a particular manner, such that the instructions stored in the computer-usable or computer-readable storage medium can also produce an article of writing that embeds the means of instruction for implementing the functions specified in the flowchart boxes. The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable data processing apparatus to produce a process executed by the computer, such that the instructions, which execute on the computer or other programmable data processing apparatus, provide steps for implementing the functions specified in the flowchart boxes.

[0044] Furthermore, each box may represent a portion of a module, segment, or code that includes one or more executable instructions for performing a specified logical function. It should also be noted that in some alternative implementations, the functions mentioned in a box may occur out of order. For example, two consecutive blocks may actually execute substantially simultaneously, or these blocks may sometimes execute in reverse order according to their corresponding functions.

[0045] In this embodiment, the term "module" refers to a software or hardware component that performs certain tasks, such as a field-programmable gate array (FPGA) or an application-specific integrated circuit (ASIC). However, "module" is not intended to be limited to software or hardware. A module can be configured to reside on an addressable storage medium or to execute one or more processors. Thus, as examples, a module may include components (such as software components, object-oriented software components, class components, and task components), procedures, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within components and "modules" can be combined into fewer components and modules, or can be further divided into additional components and modules. Additionally, components and modules can be implemented such that they execute one or more central processing units (CPUs) in a device or secure multimedia card. Furthermore, in this embodiment, a module may include one or more processors.

[0046] Wireless communication systems that provided early voice-oriented services are evolving into broadband wireless communication systems that provide high-speed, high-quality packet data services, such as High-Speed ​​Packet Access (HSPA), LTE (or Evolved Universal Terrestrial Radio Access (E-UTRA)), Advanced LTE (LTE-A), and LTE-Pro as defined in 3GPP, High-Rate Packet Data (HRPD) as defined in 3GPP-2, Ultra Mobile Broadband (UMB), and the 802.16e communication standard defined by the Institute of Electrical and Electronics Engineers (IEEE).

[0047] As a representative example of a broadband wireless communication system, the LTE system employs an Orthogonal Frequency Division Multiplexing (OFDM) scheme for the downlink (DL) and a Single Carrier Frequency Division Multiple Access (SC-FDMA) scheme for the uplink (UL). The uplink is the radio link through which a User Equipment (UE) (or Mobile Station (MS)) transmits data or control signals to a Base Station (BS) (or eNode B), and the downlink is the radio link through which the BS transmits data or control signals to the UE. In the multiple access scheme described above, time-frequency resources used to carry data or control information are allocated and operated in a manner that prevents resource overlap between users (i.e., establishes orthogonality) in order to identify the data or control information of each user.

[0048] As the next-generation communication system after LTE, 5G communication systems should meet the diverse service requirements of users and service providers. The services supported by 5G systems can be categorized into three types: enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable and low-latency communications (URLLC).

[0049] Compared to the data rates supported by traditional LTE, LTE-A, and LTE-Pro, eMBB aims to provide extremely high data rates. For example, from a base station's perspective, eMBB should provide peak data rates of up to 20 Gbps in the downlink and up to 10 Gbps in the uplink. Simultaneously, 5G communication systems should provide both peak data rates and increased user-perceived data rates for the terminal. Meeting these requirements necessitates improvements to various transmit / receive technologies, including more advanced multiple-input multiple-output (MIMO) transmission techniques. Furthermore, while LTE transmits signals using a maximum transmission bandwidth of 20 MHz in the 2 GHz band, 5G communication systems can meet the required data transmission rates by using frequency bandwidths wider than 20 MHz in the 3 to 6 GHz or 6 GHz or higher bands.

[0050] Simultaneously, mMTC is being considered to support application services such as the Internet of Things (IoT) within 5G communication systems. To effectively deliver IoT, mMTC requires support for massive terminal access within a cell, enhanced terminal coverage, improved battery life, and reduced terminal costs. Because IoT attaches to various sensors and devices to provide communication capabilities, it must be able to support a large number of terminals within a cell (e.g., 1,000,000 terminals / km²). Furthermore, because, depending on the nature of the service, mMTC-enabled terminals may be located in shadowed areas not covered by cell coverage (such as building basements), mMTC may require wider coverage compared to other services offered in 5G communication systems. Terminals supporting mMTC must be configured as low-cost terminals, and because it is difficult to frequently replace terminal batteries, very long battery life, such as 10 to 15 years, may be required.

[0051] Finally, in the case of URLLC, it is a cellular-based wireless communication service for specific (mission-critical) purposes. For example, services such as remote control of robots or machinery, industrial automation, unmanned aerial vehicles, remote healthcare, and emergency alerts could be considered. Therefore, the communication provided by URLLC should offer very low latency and very high reliability. For example, services supporting URLLC should meet an air interface latency of less than 0.5 milliseconds and simultaneously have 10... -5 Or a lower packet error rate requirement. Therefore, for services supporting URLLC, 5G systems should provide shorter transmission time intervals (TTIs) than other services, and at the same time, design specifications may be required whereby extensive resources should be allocated in the frequency band to ensure the reliability of the communication link.

[0052] Three 5G services—eMBB, URLLC, and mMTC—can be reused and transmitted within a single system. In this case, different transmit / receive schemes and parameters can be used to meet the different requirements of each service. Of course, 5G is not limited to these three services.

[0053] [NR Time and Frequency Resources]

[0054] Figure 1 This is a diagram illustrating the basic structure of the time-frequency domain in a 5G system, which is the radio resource region for transmitting data or control channels.

[0055] exist Figure 1 In the diagram, the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. The basic unit of a resource in the time-frequency domain is a resource element (RE) 101, which can be defined as an orthogonal frequency division multiplexing (OFDM) symbol 102 on the time axis and a subcarrier 103 on the frequency axis. In the frequency domain, One (e.g., twelve) consecutive REs can constitute a resource block (RB) 104. In the time domain, One OFDM symbol can form a subframe 110.

[0056] Figure 2 The frame, subframe, and time slot structure in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0057] exist Figure 2 The diagram illustrates an example of the structure of frame 200, subframe 201, and time slot 202. One frame 200 can be defined as 10 ms. One subframe 201 can be defined as 1 ms, and therefore one frame 200 can include a total of 10 subframes 201. One time slot 202 or 203 can be defined as 14 OFDM symbols (i.e., the number of symbols per time slot). =14). A subframe 201 may include one or more time slots 202 and 203, and the number of time slots 202 or 203 in each subframe 201 may vary depending on the configuration value μ 204 or 205 used for the subcarrier spacing. Figure 2 The example shows the cases where the subcarrier spacing configuration value μ=0204 and μ=1205. In the case of μ=0204, one subframe 201 can include one time slot 202, and in the case of μ=1205, one subframe 201 can include two time slots 203. That is, the number of time slots in each subframe ( The number of time slots per frame can vary depending on the configured value (μ) of the subcarrier spacing. The value can vary depending on the number of subcarrier spacing configuration values ​​(μ). ) and quantity ( ) can be defined as shown in [Table 1] below.

[0058] [Table 1]

[0059] [Bandwidth Component (BWP)]

[0060] The configuration of the bandwidth portion (BWP) in a 5G communication system will then be described in detail with reference to the accompanying drawings.

[0061] Figure 3 This shows an example of BWP configuration in a 5G communication system.

[0062] exist Figure 3In this configuration, UE bandwidth 300 is divided into two bandwidth portions, namely BWP#1 301 and BWP#2 302. A BS can configure one or more BWPs in the UE, and the information in Table 2 can be configured for each BWP.

[0063] [Table 2]

[0064] Of course, this disclosure is not limited to this example, and various parameters and configuration information related to the BWP can be configured in the UE. This information can be sent from the BS to the UE via higher-layer signaling (e.g., Radio Resource Control (RRC) signaling). Among one or more configured BWPs, at least one BWP can be activated. Information indicating whether a configured BWP is activated can be semi-statically transmitted from the BS to the UE via RRC signaling, or dynamically transmitted via downlink control information (DCI).

[0065] According to an embodiment, prior to Radio Resource Control (RRC) connection, the UE can receive the initial BWP configuration for initial access from the BS via the Master Information Block (MIB). More specifically, during the initial access step, the UE can receive configuration information for the Control Resource Set (CORESET) and search space via the MIB. In the CORESET and search space, a PDCCH can be transmitted for receiving system information (Residual System Information (RMSI) or System Information Block 1 (SIB1)) required for initial access. The Control Resource Set and search space configured as the MIB can be considered as ID 0. The BS can notify the UE of configuration information via the MIB, such as frequency allocation information, time allocation information, parameter sets, etc., for Control Resource Set #0. Furthermore, the BS can notify the UE of the configuration information for the monitoring period and timing of Control Resource Set #0, i.e., the configuration information for search space #0, via the MIB. The UE can consider the frequency region configured to be obtained from the MIB as the initial bandwidth portion for initial access. In this case, the ID of the initial BWP can be considered as 0.

[0066] The BWP configuration supported by the 5G system can be used for a variety of purposes.

[0067] According to the implementation method, when the bandwidth supported by the UE is narrower than the system bandwidth, it can be supported through BWP configuration. For example, the BS can configure the frequency position of the BWP in the UE (configuration information 2), and thus the UE can send and receive data at a specific frequency position within the system bandwidth.

[0068] Furthermore, according to embodiments, to support different parameter sets, the BS can configure multiple BWPs in the UE. For example, to support the UE using both 15 kHz and 30 kHz subcarrier spacings for data transmission and reception, two BWPs can be configured with subcarrier spacings of 15 kHz and 30 kHz, respectively. Different BWPs can be frequency-division multiplexed, and when data needs to be transmitted and received with a specific subcarrier spacing, the BWP configured with the corresponding subcarrier spacing can be activated.

[0069] According to an embodiment, to reduce the power consumption of the UE, the BS can configure a BWP with different bandwidth sizes in the UE. For example, when the UE supports a very large bandwidth (e.g., 100 MHz) but always transmits and receives data through that bandwidth, very high power consumption may be generated. In particular, monitoring unnecessary downlink control channels through a large bandwidth of 100 MHz in the absence of traffic is very inefficient in terms of power consumption. To reduce the power consumption of the UE, the BS can configure a BWP with a relatively narrow bandwidth (e.g., 20 MHz). The UE can perform monitoring operations in the 20 MHz bandwidth portion in the absence of traffic, and if data is generated, it can transmit and receive data through the 100 MHz bandwidth portion according to instructions from the BS.

[0070] In the method of configuring the BWP, the UE prior to RRC connection can receive configuration information for the initial bandwidth portion via the Master Information Block (MIB) during the initial access step. More specifically, the UE can receive the configuration of the Control Resource Set (CORESET) for the downlink control channel from the MIB of the Physical Broadcast Channel (PBCH), in which downlink control information (DCI) for scheduling System Information Blocks (SIBs) can be transmitted. The bandwidth of the Control Resource Set configured as the MIB can be considered as the initial bandwidth portion, and the UE can receive the Physical Downlink Shared Channel (PDSCH) through which the SIBs are transmitted via the configured initial bandwidth portion. The initial BWP can be used not only for receiving SIBs but also for other System Information (OSI), paging, or random access.

[0071] [SS / PBCH block]

[0072] The synchronization signal (SS) / PBCH block in 5G is then described.

[0073] The SS / PBCH block can be a physical layer channel block that includes the primary SS (PSS), secondary SS (SSS), and PBCH. It will be described in detail below.

[0074] -PSS: This is a signal that serves as a reference for downlink time / frequency synchronization and provides some information about the cell ID.

[0075] -SSS: This is the reference for downlink time / frequency synchronization and provides residual cell ID information not provided by PSS. Additionally, SSS is used as a reference signal for demodulation in PBCH.

[0076] -PBCH: Provides the necessary system information required by the UE to transmit and receive data and control channels. This necessary system information may include search space-related control information indicating radio resource mapping information for control channels and scheduling control information for separate data channels used to transmit system information.

[0077] -SS / PBCH blocks: Includes a combination of PSS, SSS, and PBCH. One or more SS / PBCH blocks can be sent within 5 ms, and each sent SS / PBCH block can be separated by an index.

[0078] During the initial access phase, the UE can detect the PSS and SSS and decode the PBCH. The UE can obtain the MIB from the PBCH and receive the configuration of Control Resource Set (CORESET) #0 (corresponding to the Control Resource Set with Control Resource Set Index 0). The UE can monitor Control Resource Set #0 based on the selected SS / PBCH block and the assumption that the Demodulation Reference Signal (DMRS) transmitted in Control Resource Set #0 is quasi-co-located (QCLed). The UE can receive system information via downlink control information transmitted in Control Resource Set #0. The UE can obtain configuration information related to the Random Access Channel (RACH) required for initial access from the received system information. The UE can send a Physical RACH (PRACH) to the BS considering the selected SS / PBCH block index, and the BS receiving the PRACH can obtain information about the SS / PBCH block index selected by the UE. The BS can know which block the UE selected from the SS / PBCH blocks and the associated CORESET #0 being monitored.

[0079] [PDCCH: About DCI]

[0080] Then, the downlink control information (DCI) in the 5G system is described in detail.

[0081] In 5G systems, scheduling information for uplink data (or physical uplink data channel (PUSCH)) or downlink data (or physical downlink data channel (PDSCH)) is transmitted from the BS to the UE via DCI. The UE can monitor the backoff DCI format and the non-backoff DCI format of the PUSCH or PDSCH. The backoff DCI format may include predefined fixed fields between the BS and the UE, while the non-backoff DCI format may include configurable fields.

[0082] DCI messages can be transmitted via the Physical Downlink Control Channel (PDCCH) through channel coding and modulation processes. Cyclic Redundancy Check (CRC) can be added to the DCI message payload and can be scrambled by a Radio Network Temporary Identifier (RNTI) corresponding to the UE's identity. Depending on the purpose of the DCI message, such as UE-specific data transmission, power control commands, random access responses, etc., different RNTIs can be used. That is, the RNTI is not explicitly transmitted but is included in the CRC calculation process. If a DCI message is received via the PDCCH, the UE can identify the CRC using the assigned RNTI, and when the CRC is determined to be correct based on the CRC identification result, the UE can recognize that the corresponding message was sent to the UE.

[0083] For example, the DCI used to schedule PDSCH for System Information (SI) can be scrambled by SI-RNTI. The DCI used to schedule PDSCH for Random Access Response (RAR) messages can be scrambled by RA-RNTI. The DCI used to schedule PDSCH for paging messages can be scrambled by P-RNTI. The DCI used to notify Slot Format Indicator (SFI) can be scrambled by SFI-RNTI. The DCI used to notify Transmit Power Control (TPC) can be scrambled by TPC-RNTI. The DCI used to schedule UE-specific PDSCH or PUSCH can be scrambled by Cell RNTI (C-RNTI).

[0084] DCI format 0_0 can be used for backoff DCI scheduling of PUSCH, in which case CRC can be scrambled by C-RNTI. The DCI format 0_0 with CRC scrambled by C-RNTI can include, for example, information from Table 3.

[0085] [Table 3]

[0086] DCI format 0_1 ​​can be used for non-back-off DCI scheduling of PUSCH, in which case CRC can be scrambled by C-RNTI. DCI format 0_1 ​​with CRC scrambled by C-RNTI can include, for example, the following information from Table 4.

[0087] [Table 4]

[0088]

[0089]

[0090] DCI format 1_0 can be used to schedule the back-off DCI of PDSCH, in which case the CRC can be scrambled by C-RNTI. The DCI format 1_0 with CRC scrambled by C-RNTI can include, for example, the information in Table 5.

[0091] [Table 5]

[0092] DCI format 1_1 can be used for non-back-off DCI scheduling of PDSCH, in which case CRC can be scrambled by C-RNTI. The DCI format 1_1 with CRC scrambled by C-RNTI can include, for example, information from Table 6.

[0093] [Table 6]

[0094]

[0095] [PDCCH: CORESET, REG, CCE, Search Space]

[0096] The downlink control channel in a 5G communication system is then described in more detail with reference to the accompanying drawings.

[0097] Figure 4 An example of the control resource set (CORESET) for transmitting downlink control channels in a 5G wireless communication system is shown.

[0098] Figure 4 An example is shown where a UE bandwidth portion 410 is configured on the frequency axis and two control resource sets (control resource set #1 401 and control resource set #2 402) are configured within one timeslot 420 on the time axis. Control resource sets 401 and 402 can be configured within specific frequency resources 403 within the total UEBWP 410 on the frequency axis. A control resource set can be configured as one or more OFDM symbols on the time axis, and can be defined as a control resource set duration 404. Reference Figure 4In the example shown, control resource set #1 401 is configured for a control resource set duration of 2 symbols, and control resource set #2 402 is configured for a control resource set duration of 1 symbol.

[0099] The BS can configure the control resource set in the 5G system within the UE via higher-layer signaling (e.g., system information, Master Information Block (MIB), or Radio Resource Control (RRC) signaling). Configuring the control resource set in the UE can mean providing information such as the control resource set identifier, the frequency location of the control resource set, and the symbol length of the control resource set. For example, it may include the information in Table 7.

[0100] [Table 7]

[0101]

[0102] In Table 7, the tci-StatesPDCCH (referred to as Transmission Configuration Indication (TCI) status) configuration information may include information about one or more Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) block indices or Channel State Information Reference Signal (CSI-RS) indices that have a quasi-co-located (QCL) relationship with the DMRS transmitted in the corresponding CORESET.

[0103] Figure 5a An example is shown of the basic units that constitute the time and frequency resources of the downlink control channel that can be used in 5G.

[0104] refer to Figure 5a The basic unit constituting the time and frequency resources of the control channel can be a resource element group (REG) 503, and REG 503 can be defined as an OFDM symbol 501 on the time axis and a physical resource block (PRB) 502 on the frequency axis, i.e., 12 subcarriers. The BS can configure the downlink control channel allocation unit by splicing REG 503.

[0105] like Figure 5a As shown, when the basic unit for allocating downlink control channels in 5G is a control channel element (CCE) 504, one CCE 504 can be composed of multiple REG 503s. This is illustrated through an example. Figure 5aAs shown in the description of REG 503, REG 503 can consist of 12 REs, and when a CCE 504 consists of 6 REG 503s, a CCE 504 can consist of 72 REs. When configuring a downlink control resource set, the corresponding control resource set can consist of multiple CCE 504s, and a specific downlink control channel can be mapped to one or more CCE 504s according to the aggregation level (AL) within the control resource set, and then transmitted. CCE 504s within the control resource set can be distinguished by number, and the numbering of CCEs 504s can be assigned according to a logical mapping scheme.

[0106] Figure 5a The basic unit of the downlink control channel shown (i.e., REG 503) may include all REs to which the DCI is mapped and the area to which the DMRS 505 is mapped as a reference signal for decoding it. Figure 5a In this configuration, three DMRS 505s can be transmitted within a single REG 503. Depending on the aggregation level (AL), the number of CCEs required to transmit the PDCCH can be 1, 2, 4, 8, or 16, and different numbers of CCEs can be used to achieve link adaptation of the downlink control channel. For example, with AL=1, one downlink control channel can be transmitted using L CCEs. The UE is required to detect signals without knowing information about the downlink control channel, and a search space for the set of CCEs indicating the downlink control channel is defined for blind decoding. The search space is the set of downlink control channel candidates consisting of CCEs that the UE should attempt to decode at a given aggregation level, and there are several aggregation levels that form a bundle of 1, 2, 4, 8, and 16 CCEs, allowing the UE to have multiple search spaces. The search space set can be defined as the set of search spaces for all configured aggregation levels.

[0107] The search space can be categorized into a common search space and a UE-specific search space. UEs or all UEs in a pre-defined group can search the common search space of the PDCCH to receive cell common control information, such as dynamic scheduling of system information or paging messages. For example, searching the common search space of the PDCCH can be used to receive PDSCH scheduling allocation information for transmitting SIBs including cell operator information. In the case of a common search space, UEs or all UEs in the pre-defined group should receive the PDCCH, such that the common search space can be defined as a pre-arranged set of CCEs. Searching the UE-specific search space of the PDCCH can be used to receive scheduling allocation information for UE-specific PDSCHs or PUSCHs. The UE-specific search space can be UE-specifically defined as a function of the UE identifier and various system parameters.

[0108] In 5G, the BS can configure parameters for the search space used for PDCCH in the UE via higher-layer signaling (e.g., SIB, MIB, or RRC signaling). For example, the BS can configure in the UE the number of PDCCH candidates for each aggregation level L, the monitoring periodicity of the search space, the timing of monitoring in symbol units within the time slots of the search space, the search space type (common search space or UE-specific search space), the combination of DCI format and RNTI to be monitored in the corresponding search space, and the control resource set index used to monitor the search space, etc. For example, the information in [Table 8] can be included.

[0109] [Table 8]

[0110]

[0111]

[0112] The BS can configure one or more search space sets in the UE based on configuration information. According to some embodiments, the BS can configure search space set 1 and search space set 2 in the UE, and can configure the UE to monitor DCI format A scrambled by X-RNTI in search space set 1 in a common search space, and monitor DCI format B scrambled by Y-RNTI in search space set 2 in a UE-specific search space.

[0113] Depending on the configuration information, one or more search space sets may exist in the public search space or the UE-specific search space. For example, search space set #1 and search space set #2 can be configured as a public search space, and search space set #3 and search space set #4 can be configured as UE-specific search spaces.

[0114] In the public search space, the following combinations of DCI format and RNTI can be monitored. Of course, this disclosure is not limited to the following examples.

[0115] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, and SI-RNTI.

[0116] - DCI format 2_0 with CRC scrambled by SFI-RNTI

[0117] - DCI format 2_1 with CRC scrambled by INT-RNTI

[0118] - DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI and TPC-PUCCH-RNTI

[0119] - DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

[0120] Within a UE-specific search space, the following combinations of DCI format and RNTI can be monitored. Of course, this disclosure is not limited to the following examples.

[0121] - DCI format 0_0 / 1_0 with CRC scrambled by C-RNTI, CS-RNTI, and TC-RNTI.

[0122] - DCI format 1_0 / 1_1 with CRC scrambled by C-RNTI, CS-RNTI, and TC-RNTI.

[0123] The specified RNTI can follow the following definitions and uses.

[0124] Cell RNTI (C-RNTI): Used for UE-specific PDSCH scheduling

[0125] - Temporary Cell RNTI (TC-RNTI): Used for UE-specific PDSCH scheduling

[0126] Configuration-based scheduling RNTI (CS-RNTI): UE-specific PDSCH scheduling for semi-static configuration.

[0127] Random Access RNTI (RA-RNTI): Used for PDSCH scheduling during the random access phase.

[0128] Paging RNTI (P-RNTI): PDSCH scheduling used to send paging messages.

[0129] System Information RNTI (SI-RNTI): Used by the PDSCH scheduler to send system information.

[0130] Interrupt RNTI (INT-RNTI): Used to indicate whether puncturing is performed on the PDSCH.

[0131] Transmit Power Control RNTI for PUSCH (TPC-PUSCH-RNTI): Used to indicate PUSCH power control commands.

[0132] Transmit Power Control RNTI for PUCCH (TPC-PUCCH-RNTI): Used to indicate PUCCH power control commands.

[0133] Transmit Power Control RNTI for SRS (TPC-SRS-RNTI): Used to indicate SRS power control commands.

[0134] The DCI format specified above can follow the following definition.

[0135] [Table 9]

[0136] In 5G, the search space at the aggregation level L in the control resource set p and the search space set s can be expressed as shown in Equation 1 below.

[0137] [Equation 1]

[0138] L: Aggregation Level

[0139] - Carrier index

[0140] - : The total number of CCEs in the control resource set p

[0141] - Time slot index

[0142] - Number of PDCCH candidates at aggregation level L

[0143] - =0,…, -1: Index of PDCCH candidates at aggregation level L

[0144] -i=0,...,L-1

[0145] - , , for , , for , , for , , D=65537.

[0146] UE identifier

[0147] In the context of public search spaces, The value can correspond to 0.

[0148] In the case of a specific search space for the UE The value can correspond to a value that varies depending on the UE identifier (C-RNTI or the ID configured in the UE by the BS) and the time index.

[0149] Because multiple search space sets can be configured with different parameters in 5G (e.g., the parameters in Table 8), the set of search space sets monitored by the UE can be different each time. For example, when search space set #1 is configured periodically in slot X and search space set #2 is configured periodically in slot Y, and X and Y are different from each other, the UE can monitor all search space sets #1 and #2 in a specific slot, and monitor one of search space sets #1 and #2 in another specific slot.

[0150] When a UE has multiple PDCCH monitoring opportunities within a time slot, the UE can perform a UE capability report for each subcarrier interval. In this case, the concept of a "span" can be used. A span refers to the consecutive symbols of the PDCCH that the UE can monitor within a time slot, and each PDCCH monitoring opportunity can be within one span. The span can be expressed as (X, Y), where X represents the minimum number of symbols that should be spaced between the first symbols of two consecutive spans, and Y represents the number of consecutive symbols of the PDCCH that can be monitored within one span. In this case, the UE can monitor the PDCCH within a segment of Y symbols starting from the first symbol of the span.

[0151] Figure 5b This diagram illustrates a scenario in a wireless communication system where a UE can have multiple PDCCH monitoring opportunities within a time slot across a span.

[0152] For the span, (X, Y) = (7, 4), (4, 3), and (2, 2) are possible, and these three cases are... Figure 5b The expressions are (5b-00), (5b-05), and (5b-10). For example, (5b-00) expresses the case where there are two spans in the time slot that can be expressed by (7,4). The interval between the first symbols of the two spans is expressed as X=7, the PDCCH monitoring opportunity can exist within a total of Y=3 symbols from the first symbol of each span, and search spaces 1 and 2 exist within Y=3 symbols. In another example, (5b-05) expresses the case where there are a total of three spans in the time slot that can be expressed by (4,3), and the interval between the second and third spans is X'=5 symbols, which is greater than X=4.

[0153] [PUSCH: Related to transmission scheme]

[0154] Next, the scheduling scheme for PUSCH transmissions is described. PUSCH transmissions can be dynamically scheduled by UL authorization within the DCI, or they can be operated by configuring authorization type 1 or type 2. Dynamic scheduling of PUSCH transmissions can be indicated by DCI format 0_0 or 0_1.

[0155] Configuration authorization type 1 PUSCH transports can be semi-statically configured by receiving the configuredGrantConfig, which includes rrc-ConfiguredUplinkGrant, from [Table 10] via higher-layer signaling, without receiving UL authorization within the DCI. After receiving the configuredGrantConfig, which does not include rrc-ConfiguredUplinkGrant, from [Table 10] via higher-layer signaling, configuration authorization type 2 PUSCH transports can be semi-persistently scheduled via UL authorization within the DCI. When a PUSCH transport undergoes configuration authorization, the parameters applied to the PUSCH transport are applied via the configuredGrantConfig, which is also a higher-layer signaling parameter in [Table 10], in addition to the scaling of dataScramblingIdentityPUSCH, txConfig, codebookSubset, maxRank, and UCI-OnPUSCH provided by pusch-Config from [Table 11] as higher-layer signaling. When the UE receives the transformPrecoder in the configuredGrantConfig as a higher-layer signaling in [Table 10], the UE applies the tp-pi2BPSK in the pusch-Config in [Table 11] to the PUSCH transmission through the configuration grant operation.

[0156] [Table 10]

[0157] The PUSCH transmission method is then described.

[0158] The DMRS antenna port used for PUSCH transmission is the same as the antenna port used for SRS transmission. PUSCH transmission can follow either a codebook-based transmission method or a non-codebook-based transmission method, depending on whether the value of txConfig in pusch-Config [Table 11], which is a higher-layer signaling, is "codebook" or "nonCodebook".

[0159] As described above, PUSCH transmissions can be dynamically scheduled via DCI format 0_0 or 0_1, or configured semi-statically via configuration authorization. When the UE receives an indication for PUSCH transmission scheduling via DCI format 0_0, the UE performs beam configuration for PUSCH transmission using the pucch-spatialRelationInfoID corresponding to the UE-specific PUCCH resource corresponding to the smallest ID within the active uplink BWP in the serving cell, and at this time, PUSCH transmission is based on a single antenna port. The UE does not expect PUSCH transmission scheduling via DCI format 0_0 within a BWP that does not have a PUCCH resource including pucch-spatialRelationInfo configured. If the UE does not receive the txConfig configuration within the pusch-Config in [Table 11], the UE does not expect to receive scheduling via DCI format 0_1.

[0160] [Table 11]

[0161] The codebook-based PUSCH transmission is then described.

[0162] Codebook-based PUSCH transmissions can be dynamically scheduled using DCI format 0_0 or 0_1, or operated semi-statically using configuration authorization. When codebook-based PUSCH is dynamically scheduled using DCI format 0_1 ​​or semi-statically configured using configuration authorization, the UE determines the precoder used for PUSCH transmission based on the SRS resource indicator (SRI), the transport precoding matrix indicator (TPMI), and the transport rank (the number of PUSCH transport layers).

[0163] At this point, the SRI can be given through the SRS resource indicator field within the DCI, or configured through the srs-ResourceIndicator as higher-layer signaling. In codebook-based PUSCH transmission, the UE can receive configurations of at least one to up to two SRS resources. When the UE receives an SRI through the DCI, the SRS resource indicated by the corresponding SRI is the SRS resource corresponding to the SRI among those SRS resources transmitted earlier than the PDCCH containing the corresponding SRI. Furthermore, the TPMI and transport rank can be given through field information and the number of layers within the DCI, or configured through precodingAndNumberOfLayers as higher-layer signaling. The TPMI is used to indicate the precoder applied to the PUSCH transmission. If the UE receives the configuration of one SRS resource, the TPMI is used to indicate the precoder to be applied to the configured SRS resource. If the UE receives the configuration of multiple SRS resources, the TPMI is used to indicate the precoder to be applied to the SRS resources indicated by the SRI.

[0164] The precoder to be used for PUSCH transmission is selected from the uplink codebook, which has the same number of antenna ports as the value of nrofSRS-Ports in the SRS-Config as higher-layer signaling. In codebook-based PUSCH transmission, the UE determines the codebook subset based on TPMI and the codebookSubset in the pusch-Config as higher-layer signaling. Based on the UE capabilities reported by the UE to the BS, the codebookSubset in the pusch-Config as higher-layer signaling can be configured as one of "fullyAndPartialAndNonCoherent", "partialAndNonCoherent", or "nonCoherent". If the UE reports "partialAndNonCoherent" as a UE capability, the UE does not expect the value of the codebookSubset as higher-layer signaling to be configured as "fullyAndPartialAndNonCoherent". Furthermore, if the UE reports "nonCoherent" as a UE capability, the UE does not expect the value of the codebookSubset as higher-layer signaling to be configured as either "fullyAndPartialAndNonCoherent" or "partialAndNonCoherent". When nrofSRS-Ports in SRS-ResourceSet, used as higher-layer signaling, indicates two SRS antenna ports, the UE does not expect the value of codebookSubset, used as higher-layer signaling, to be configured as "partialAndNonCoherent".

[0165] The UE can receive the configuration of an SRS resource set. The usage value in the SRS-ResourceSet, used as higher-layer signaling, is configured as "codebook," and an SRS resource can be indicated via the SRI in the corresponding SRS resource set. If several SRS resources are configured in the SRS resource set, and the usage value in the SRS-ResourceSet, used as higher-layer signaling, is configured as "codebook," the UE expects to configure the same value for nrofSRS-Ports in the SRS-Resource, used as higher-layer signaling, for all SRS resources.

[0166] The UE sends one or more SRS resources from the SRS resource set, configured with the usage value of the "codebook," to the BS according to higher-layer signaling. The BS selects one SRS resource from the SRS resources sent by the UE and instructs the UE to perform PUSCH transmission using the transmission beam information of the corresponding SRS resource. In this codebook-based PUSCH transmission, the SRI is used as an index for selecting an SRS resource and is included in the DCI. Additionally, the BS may include information in the DCI indicating the TPMI and rank to be used by the UE for PUSCH transmission. The UE performs PUSCH transmission by using the SRS resource indicated by the SRI, based on the transmission beam of the corresponding SRS resource, and applying the indicated rank and the precoder indicated by the TPMI.

[0167] Subsequently, non-codebook-based PUSCH transmissions are described. Non-codebook-based PUSCH transmissions can be dynamically scheduled via DCI format 0_0 or 0_1, or operated semi-statically via configuration authorization. When at least one SRS resource is configured within an SRS resource set, and the usage value within the SRS-ResourceSet (as higher-layer signaling) is configured as "nonCodebook", the UE can receive scheduling of non-codebook-based PUSCH transmissions via DCI format 0_1.

[0168] For an SRS resource set where the usage value within the SRS-ResourceSet (as higher-layer signaling) is configured as "nonCodebook", the UE can receive a configuration for a connected non-zero power CSI-RS (NZP CSI-RS). The UE can calculate the precoder for SRS transmission by measuring the NZP CSI-RS resources connected to the SRS resource set. If the difference between the last received symbol of an aperiodic NZP CSI-RS resource connected to the SRS resource set and the first symbol of an aperiodic SRS transmission in the UE is less than 42 symbols, the UE does not expect to update the precoder information for SRS transmission.

[0169] When the resource type value within the higher-layer signaling SRS-ResourceSet is configured as "aperiodic", the connected NZP CSI-RS is indicated by an SRS request, which is a field within DCI format 0_1 ​​or 1_1. In this case, when the connected NZP CSI-RS resource is an aperiodic NZP CSI-RS resource, it can indicate the existence of a connected NZP CSI-RS if the value of the SRS request field within DCI format 0_1 ​​or 1_1 is not "00". In this case, the corresponding DCI should not indicate cross-carrier or cross-BWP scheduling. Furthermore, if the SRS request value indicates the existence of an NZP CSI-RS, the corresponding NZP CSI-RS is located in the time slot transmitting the PDCCH including the SRS request field. In this case, the TCI state configured in the scheduled subcarrier is not configured as QCL-TypeD.

[0170] If a periodic or semi-persistent SRS resource set is configured, the associated CSI-RS within the SRS-ResourceSet as higher-layer signaling can indicate the connected NZP CSI-RS. For non-codebook-based transmissions, the UE does not expect spatialRelationInfo as higher-layer signaling for SRS resources and associated CSI-RS within the SRS-ResourceSet as higher-layer signaling to be configured together.

[0171] When a UE receives configurations for multiple SRS resources, it can determine the precoder and transmission rank to be applied to the PUSCH transmission based on the SRI indicated by the BS. In this case, the SRI can be indicated by the SRS resource indicator field within the DCI, or configured via the srs-ResourceIndicator as higher-layer signaling. Similar to the codebook-based PUSCH transmission described above, when the UE receives an SRI via the DCI, the SRS resource indicated by the corresponding SRI is the SRS resource corresponding to the SRI that was transmitted earlier than the PDCCH containing the corresponding SRI. The UE can use one or more SRS resources for SRS transmission, and the maximum number of SRS resources that can be transmitted simultaneously within the same symbol in an SRS resource set, as well as the maximum number of SRS resources, is determined by the UE's capabilities reported to the BS. In this case, the SRS resources transmitted simultaneously by the UE occupy the same RB. The UE configures one SRS port for each SRS resource. Only one SRS resource set can be configured in an SRS resource set where the usage value within the SRS-ResourceSet, which serves as higher-layer signaling, is configured as “nonCodebook”, and up to four SRS resources can be configured for non-codebook-based PUSCH transmissions.

[0172] The BS sends an NZP-CSI-RS connected to the SRS resource set to the UE, and the UE calculates a precoder to be used for transmission of one or more SRS resources within the corresponding SRS resource set based on measurements taken upon receiving the corresponding NZP-CSI-RS. When one or more SRS resources within an SRS resource set with usage configured as "nonCodebook" are sent to the BS, the UE applies the calculated precoder, and the BS selects one or more SRS resources from the received SRS resources. In this non-codebook-based PUSCH transmission, the SRI indication can express an index of one or more SRS resources or a combination of SRS resources, and the SRI is included in the DCI. The number of SRS resources indicated by the SRI sent by the BS can be the number of transport layers of the PUSCH, and the UE transmits the PUSCH by applying the precoder applied to the SRS resources to each layer.

[0173] [Related to SRS]

[0174] Subsequently, a method for estimating the uplink channel using the UE's Sounding Reference Signal (SRS) transmission is described. The BS can configure at least one SRS configuration in each uplink BWP, and configure at least one SRS resource set in each SRS configuration to send configuration information for SRS transmission to the UE. For example, the BS and UE can exchange the following higher-layer signaling information to send information related to the SRS resource set.

[0175] -srs-ResourceSetId: SRS indicates the resource set index.

[0176] -srs-ResourceIdList: A collection of SRS resource indexes that the SRS resource set references.

[0177] -resourceType: Indicates the timeline transmission configuration of the SRS resource referenced by the SRS resource set, and is configured as one of "Periodic," "Semi-persistent," and "Aperiodic." If "Periodic" or "Semi-persistent" is configured, associated CSI-RS information can be provided based on the location where the SRS resource set is used. If "Aperiodic" is configured, an aperiodic SRS resource trigger list and slot offset information can be provided, and associated CSI-RS information can be provided based on the location where the SRS resource set is used.

[0178] -usage: Indicates the configuration of the usage location of the SRS resource referenced by the SRS resource set, and is configured as one of "beamManagement", "codebook", "nonCodebook" and "antennaSwitching".

[0179] -alpha, p0, pathlossReferenceRS, srs-PowerControlAdjustmentStates: Provides parameter configuration for controlling the transmission power of SRS resources referenced by the SRS resource set.

[0180] The UE can understand that the SRS resources included in the set of SRS resource indexes referenced by the SRS resource set follow the information configured in the SRS resource set.

[0181] In addition, the BS and UE can send and receive higher-layer signaling information to transmit separate configuration information for SRS resources. For example, the separate configuration information for SRS resources may include time-frequency axis mapping information within time slots of the SRS resources, which may include information about intra- or inter-time slot frequency hopping for the SRS resources. Furthermore, the separate configuration information for SRS resources may include the time-axis transmission configuration of the SRS resources and can be configured as one of "periodic," "semi-persistent," and "aperiodic." This can be limited to having a time-axis transmission configuration, such as an SRS resource set including the SRS resources. If the time-axis transmission configuration of the SRS resources is configured as "periodic" or "semi-persistent," the SRS resource transmission periodicity and time slot offset (e.g., periodicityAndOffset) can be additionally included in the time-axis transmission configuration.

[0182] The BS can activate, deactivate, or trigger SRS transmissions to the UE via higher-layer signaling, including RRC signaling, MAC CE signaling, or L1 signaling (e.g., DCI). For example, the BS can activate or deactivate periodic SRS transmissions to the UE via higher-layer signaling. The BS can indicate the activation of an SRS resource set with a resourceType configured as periodic via higher-layer signaling, and the UE can transmit SRS resources referenced by the activated SRS resource set. The time-frequency axis resource mapping within the time slots of the transmitted SRS resources follows the resource mapping information configured in the SRS resources, and the time slot mapping, including transmission periodicity and time slot offset, follows periodicityAndOffset configured in the SRS resources. Furthermore, the spatial domain transmission filter applied to the transmitted SRS resources can reference spatial relation information configured in the SRS resources, or reference associated CSI-RS information configured in the SRS resource set including the SRS resources. The UE can transmit SRS resources within an uplink BWP activated for periodic SRS resources activated via higher-layer signaling.

[0183] For example, the BS can activate or deactivate semi-persistent SRS transmission to the UE via higher-layer signaling. The BS can indicate the activation of an SRS resource set via MAC CE signaling, and the UE can transmit SRS resources referenced by the activated SRS resource set. The SRS resource set activated via MAC CE signaling can be limited to SRS resource sets with a resourceType configured as semi-persistent. The time-frequency axis resource mapping within the timeslot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource, and the timeslot mapping, including transmission periodicity and timeslot offset, follows periodicityAndOffset configured in the SRS resource. Furthermore, the spatial domain transmission filter applied to the transmitted SRS resource can refer to spatial relation information configured in the SRS resource, or refer to associated CSI-RS information configured in the SRS resource set including the SRS resource. If spatial relation information is configured in the SRS resource, the spatial domain transmission filter can be determined by referring to the configuration information of the spatial relation information transmitted via MAC CE signaling to activate semi-persistent SRS transmission, without following the spatial relation information configured in the SRS resource. The UE can transmit SRS resources within the uplink BWP activated for semi-persistent SRS resources activated via higher-layer signaling.

[0184] For example, the BS can trigger aperiodic SRS transmissions to the UE via DCI. The BS can indicate one of the aperiodic SRS resource triggers (aperiodicSRS-ResourceTrigger) via the SRS request field of the DCI. The UE understands that an SRS resource set, including the aperiodic SRS resource trigger list indicated by the DCI, has been triggered in the SRS resource set configuration information. The UE can then transmit SRS resources referenced by the triggered SRS resource set. The time-frequency axis resource mapping within the timeslot of the transmitted SRS resource follows the resource mapping information configured in the SRS resource. Furthermore, the timeslot mapping of the transmitted SRS resource can be determined by the timeslot offset between the PDCCH including the DCI and the SRS resource, which can refer to values ​​included in the timeslot offset set configured in the SRS resource set. Specifically, the timeslot offset between the PDCCH including the DCI and the SRS resource can apply the value indicated by the time-domain resource assignment field of the DCI from the offset values ​​included in the timeslot offset set configured in the SRS resource set. Furthermore, the spatial domain transmission filter applied to the transmitted SRS resources can reference spatial relationship information configured in the SRS resources, or refer to associated CSI-RS information configured in the SRS resource set including the SRS resources. The UE can transmit SRS resources within the uplink BWP activated for aperiodic SRS resources triggered by DCI.

[0185] When the BS triggers an aperiodic SRS transmission to the UE via DCI, the UE may require a minimum time interval between the PDCCH containing the DCI that triggers the aperiodic SRS transmission and the transmitted SRS in order to transmit the SRS by applying the configuration information of the SRS resources. The time interval for the UE to transmit SRS can be defined as the number of symbols between the last symbol of the PDCCH containing the DCI that triggers the aperiodic SRS transmission and the first symbol mapped to the first transmitted SRS resource in the transmitted SRS resources. The minimum time interval can be defined with reference to the PUSCH preparation procedure time required by the UE to prepare for PUSCH transmission. Furthermore, the minimum time interval can have different values ​​depending on the usage location of the SRS resource set including the transmitted SRS resources. For example, the minimum time interval can be defined as N² symbols, taking into account the UE's processing capabilities, based on the UE's PUSCH preparation procedure. Furthermore, when the SRS resource set usage location is configured as "codebook" or "antennaSwitching", considering the usage location of the SRS resource set including the transmitted SRS resources, the minimum time interval can be determined to be N² symbols. When the SRS resource set usage location is configured as "nonCodebook" or "beamManagement", the minimum time interval can be determined to be N²+14 symbols. When the time interval used for aperiodic SRS transmission is longer than or equal to the minimum time interval, the UE can transmit aperiodic SRS, and when the time interval used for aperiodic SRS transmission is shorter than the minimum time interval, the UE can ignore the DCI that triggers aperiodic SRS.

[0186] [Table 12]

[0187] The spatialRelationInfo configuration information in Table 12 above applies to the beam of the corresponding SRS transmission used to reference the beam information of the corresponding reference signal. For example, the spatialRelationInfo configuration may include the information in Table 13 below.

[0188] [Table 13]

[0189] Referring to the `spatialRelationInfo` configuration, the SS / PBCH block index, CSI-RS index, or SRS index can be configured as the index of the reference signal to be referenced for using beam information of a specific reference signal. The higher-layer signaling `referenceSignal` is configuration information indicating which reference signal beam information is referenced for the corresponding SRS transmission. `ssb-Index` is the SS / PBCH block index, `csi-RS-Index` is the CSI-RS index, and `srs` is the SRS index. If the higher-layer signaling `referenceSignal` value is configured as "ssb-Index", the UE can apply the receive beam used to receive the SS / PBCH block corresponding to `ssb-Index` as the transmit beam for the corresponding SRS transmission. If the higher-layer signaling `referenceSignal` value is configured as "csi-RS-Index", the UE can apply the receive beam used to receive the CSI-RS corresponding to `csi-RS-Index` as the transmit beam for the corresponding SRS transmission. If the value of the higher-layer signaling referenceSignal is configured as "srs", the UE can apply the transmit beam used to transmit the SRS corresponding to srs as the transmit beam for the corresponding SRS transmission.

[0190] [Related to SRS antenna switching]

[0191] The SRS used for antenna switching is described below.

[0192] SRS can be used for downlink (DL) channel state information (CSI) acquisition (e.g., DL CSI acquisition). In a specific example, after the base station (BS) schedules SRS transmissions to the user equipment (UE) in a time-division duplex (TDD) single-cell or multi-cell (e.g., carrier aggregation (CA)) scenario, the BS can measure the SRS transmitted from the UE. In this case, based on the assumption of DL / UL reciprocity, the BS can perform DL signal / channel scheduling to the UE based on the SRS measurement. At this time, combined with the SRS-based DL CSI acquisition, the usage of the SRS resources referenced by the SRS resource set can be configured for antenna switching.

[0193] For example, when following specifications (e.g., 3GPP TS38.214), the purpose of the SRS can be configured in the BS and / or UE using higher-level parameters (e.g., the usage of the RRC parameter SRS-ResourceSet). Here, the purpose of the SRS can be set for beam management, codebook transmission, non-codebook transmission, antenna switching, etc.

[0194] The following describes in detail the case where SRS transmission (i.e., transmission of SRS resources or SRS resource sets) is configured for antenna switching as described above.

[0195] For example, in the case of UEs with partial reciprocity, SRS transmission based on antenna switching (i.e., transmit antenna switching) can be supported for DL ​​CSI acquisition via SRS transmission in scenarios such as TDD. When antenna switching is applied, the UE's antenna switching may typically require an interval of approximately 15 mm between SRS resources (and / or resources between SRS resources and PUSCH / PUCCH). Taking these issues into consideration, the (minimum) protection period can be defined as shown in Table 14.

[0196] Table 14 shows the minimum protection period based on the parameter set.

[0197] [Table 14]

[0198] In Table 14, μ indicates the parameter set. Y indicates the subcarrier spacing, and Y indicates the number of symbols in the guard period, i.e., the length of the guard period. Referring to Table 14, the guard period can be configured based on parameter μ of the determined parameter set. During the guard period, the UE can be configured not to transmit any other signals, and the guard period can be configured to be used entirely for antenna switching. For example, the guard period can be configured by considering SRS resources transmitted in the same time slot. In particular, when the UE is configured and / or indicated to transmit aperiodic SRS configured for in-slot antenna switching, the corresponding UE transmits SRS by using different transmit antennas for the corresponding specified SRS resources, and the aforementioned guard period can be configured between the corresponding resources.

[0199] Additionally, as described above, when the UE receives a configuration of SRS resources and / or SRS resource sets configured for antenna switching via higher-layer signaling, the corresponding UE can be configured to perform SRS transmission based on UE capabilities related to antenna switching. The UE can report capability information to the BS indicating whether SRS antenna switching is supported. The capability information may include parameters indicating the SRS transmission port switching modes supported by the UE. Here, the antenna switching-related UE capabilities reported by the parameters may be "1T2R", "2T4R", "1T4R", "1T4R / 2T4R", "1T1R", "2T2R", "4T4R", etc. Here, "xTyR" may indicate the UE capability that allows SRS transmission on x antenna ports across all y receive antennas.

[0200] For example, in the case of a UE supporting 1T2R, two SRS resource sets can even be configured with different values ​​for the resourceType of the higher-layer parameter SRS-ResourceSet. Here, each SRS resource set can have two SRS resources transmitted in different symbols, and each SRS resource can constitute a single SRS port in a given SRS resource set. Furthermore, the SRS port of the second SRS resource in the SRS resource set can be configured to be associated with a UE antenna port that is different from the SRS port of the first SRS resource in the same SRS resource set.

[0201] In another example, with a UE supporting 2T4R, the two SRS resource sets can even be configured with different values ​​for the resourceType of the higher-layer parameter SRS-ResourceSet. Here, each SRS resource set can have two SRS resources transmitted in different symbols, and each SRS resource can constitute two SRS ports in a given SRS resource set. Furthermore, a pair of SRS ports of the second SRS resource in the SRS resource set can be configured to be associated with UE antenna ports that are different from a pair of SRS ports of the first SRS resource in the same SRS resource set.

[0202] In another example, for a UE supporting 1T4R, the SRS resource set can be configured in different types depending on whether the SRS transmission is configured as periodic, semi-persistent, and / or aperiodic. First, when the SRS transmission is configured as periodic or semi-persistent, zero or one SRS resource set configured based on the resourceType of the higher-layer parameter SRS-ResourceSet can be configured as four SRS resources transmitted in different symbols. Here, in a given SRS resource set, each SRS resource can constitute a single SRS port. Furthermore, the SRS port of each SRS resource can be configured to be associated with a different UE antenna port. In contrast, when the SRS transmission is configured as aperiodic, zero or two SRS resource sets configured based on the resourceType of the higher-layer parameter SRS-ResourceSet can consist of a total of four SRS resources transmitted in different symbols in two different time slots. Here, the SRS port of each SRS resource in two given SRS resource sets can be configured to be associated with a different UE antenna port. Each SRS resource set can consist of two SRS resources, or one SRS resource set can consist of one SRS resource and another SRS resource set can consist of three SRS resources.

[0203] In another example, for UEs supporting 1T1R, 2T2R, or 4T4R, up to two SRS resource sets can be configured for SRS transport, each consisting of one SRS resource. The number of SRS ports for each SRS resource can be configured to 1, 2, or 4.

[0204] If the indicated UE capability is 1T4R / 2T4R, the corresponding UE can expect to configure the same number of SRS ports (e.g., 1 or 2) for all SRS resources in the SRS resource set. Furthermore, when the indicated UE capability is 1T2R, 2T4R, 1T4R, or 1T4R / 2T4R, the corresponding UE may not expect one or more SRS resource sets configured for antenna switching to be configured or triggered in the same time slot. Additionally, when the indicated UE capability is 1T1R, 2T2R, or 4T4R, the corresponding UE may not expect one or more SRS resource sets configured for antenna switching to be configured or triggered in the same time slot.

[0205] The various embodiments described above do not explicitly configure panels for at least uplink and downlink transmissions for the UE. That is, without explicitly considering UE panels, UE antenna ports for SRS antenna switching can be configured, and the BS and UE can operate accordingly. If explicit configuration of two or more panels is considered, an SRS resource set for antenna switching can be configured for each panel. In this case, UE capability exists depending on whether the corresponding SRS resource set configured for each panel can be transmitted simultaneously by the UE, configured in the same time slot, or transmitted in the same time slot.

[0206] [SRS comb offset / cyclic shift configuration]

[0207] The method for configuring comb offset and cyclic shift when the UE transmits a probe reference signal (SRS) is then described.

[0208] For SRS resources, the UE can receive the configuration of SRS-Resource or SRS-PosResource as higher-layer signaling from the BS, and it can consist of the following items.

[0209] - In the case of SRS-Resource, the UE can receive a configuration of the number of antenna ports for each SRS resource, which can be defined as follows: This configuration is received via nrofSRS-Ports or nrofSRS-Ports-n8 as higher-level signaling. If the usage as higher-level signaling within the SRS-ResourceSet is configured to a value other than nonCodebook, then p i =1000+i can refer to the number of the i-th antenna port, and i can be 0 or an integer. -1. If the usage of higher-level signaling within the SRS-ResourceSet is configured as non-Codebook, then each SRS resource can receive... =Configuration of 1 antenna port, and the antenna port of the (i+1)th SRS resource in the SRS-ResourceSet can be defined as p i =1000+i. In the case of SRS-PosResource, it can be defined as... =1.

[0210] - The UE can receive the configuration of the number of consecutive symbols used to transmit SRS via nrofSymbols within resourceMapping, which is a higher-layer signaling from the BS, and this value can be defined as .

[0211] - The UE can receive the configuration for the position of the start symbol for transmitting SRS within a time slot via the startPosition within the resourceMapping, which is a higher-layer signaling from the BS, and this value can be defined as .at this time, It can refer to the number of symbols in a time slot, and the value can be 14 in the case of a normal cyclic prefix and 12 in the case of an extended cyclic prefix. This can refer to the offset value that counts the number of symbols in reverse order from the symbol located at the very end of the time slot. In this case, it can satisfy... .

[0212] -k0 can refer to the starting position of the frequency resources used to transmit SRS.

[0213] The SRS sequence generated from the SRS resources defined based on this information can be defined as follows [Equation 2].

[0214] [Equation 2]

[0215] at this time, This refers to the length of the SRS sequence. (m) SRS,bThis is determined by [Equation 15] below, and can also be determined by b-SRS and c-SRS as higher-level signaling. At this point, when configuring b-SRS, B in [Table 15] below can be determined. SRS The value ∈{0,1,2,3} can be determined as m SRS,b The value of the subscript b, and when b-SRS is not configured, B SRS It can be 0 (B) SRS =0). c-SRS can be determined in [Table 15] below. SRS The value of ∈{0,1,…, 63}.

[0216] [Table 15]

[0217]

[0218] P can be determined by the FreqScalingFactor as a high-level signaling parameter. F ∈{2,4}, and when the corresponding parameter is not configured, P F It can be 1 (P) F =1). When the FreqScalingFactor is configured as a higher-layer signaling, the UE can expect the SRS sequence length to be a multiple of 6.

[0219] Can be defined And K TC The comb size can be determined by ∈{2,4,8}. In this case, the comb size can refer to the interval between REs used to transmit SRS in the frequency resource, and for example, when the comb size is K... TC When the value is 2, it can mean that the interval between REs used to transmit SRS is 2 REs. The UE can receive the comb size configuration through the transmission comb as higher-layer signaling. This can refer to the symbol index within the symbol used to transmit SRS resources. The UE can use K as shown in [Table 16] below. TC The value is determined as the maximum cyclic shift value. .

[0220] [Table 16]

[0221] It can be done and basic sequence The definition is as follows: This refers to the cyclic shift of the i-th antenna port.

[0222]

[0223] at this time, This can refer to the length of the SRS sequence. For a basic sequence, it can be determined based on different... and The value generates multiple SRS sequences.

[0224] Multiple basic sequences can be divided into groups, and the index of a group can be defined as u∈{0,1,…,29}, where v can refer to the index of a basic sequence within the group. If 1 / 2≤ If ≤ 5, then each group can include a basic sequence, in which case v can be 0 (v=0). If 6 ≤ Each group can include two basic sequences, in which case v can be 0 or 1 (v=0,1). The definition can depend on M as the sequence length. ZC The value changes accordingly.

[0225] When the basic sequence length is 36 or longer, that is, At that time, the basic sequence It can be defined as follows. At this time, N ZC It can be less than M ZC The largest prime number.

[0226]

[0227] When the length of the basic sequence is 6, 12, 18, or 24, that is, M ZC When ∈{6,12,18,24}, the basic sequence It can be defined as follows.

[0228]

[0229] At this point, M can be defined based on index u using Tables 17 to 20 below. ZC of The value of .

[0230] When the length of the basic sequence is 30, that is, M ZC When =30, the basic sequence It can be defined as follows.

[0231]

[0232] If the UE receives the configuration as ports8tdm, then the configuration is nrofSRS-Ports-n8, which is used as higher-layer signaling. It can be defined as follows; otherwise, it can be defined as follows. =1.

[0233] -if And p i If ∈{1000,1001,1004,1005}, then we can define =1.

[0234] -if And p i If ∈{1002, 1003, 1006, 1007}, then we can define =1.

[0235] -In cases other than the two mentioned above, it is possible to define =0.

[0236] This indicates the corresponding antenna port p i Circular shift It can be defined as follows.

[0237]

[0238] at this time, It can be defined as follows.

[0239] -when =8 and When =6, it can be defined .

[0240] -when =4 and =6 or =8 and When =12, Can be defined .

[0241] -In cases other than the two mentioned above, it is possible to define .

[0242] at this time, These are parameters that determine the cyclic shift value, and can be configured via cyclicShift-n2, cyclicShift-n4, or cyclicShift-n8 within the transmissionComb as higher-level signaling. This can be determined using [Table 16] above.

[0243] and This can be determined as follows.

[0244] - If nrofSRS-Ports-n8, used as higher-level signaling, is configured as ports8tdm, then it can be defined =4, and about , in pi When -1000 < 4, it can be defined =1000+p i mod 2, and in p i When -1000≥4, it can be defined as =1000+p i mod 2+2. That is, when transmitting SRS resources consisting of 8 antenna ports of TDM type, the UE can specify the antenna port p to be transmitted in the first symbol. i =1000, 1001, 1004, and 1005 are defined respectively. = 1000, 1001, 1002, 1003 and for the antenna port p to be transmitted in the second symbol i =1002, 1003, 1006, and 1007 are defined respectively = 1000, 1001, 1002, 1003, and when allocating resources to four different antenna ports transmitted in the corresponding symbols, the resource allocation method for SRS resources consisting of four antenna ports can be applied as is.

[0245] - In cases other than those mentioned above, i.e., when nrofSRS-Ports-n8, as a higher-level signaling protocol, is not configured as ports8tdm, it is possible to define = and =p i .

[0246] This indicates the starting position in the frequency dimension of the SRS corresponding to the i-th antenna port. It can be defined as follows.

[0247]

[0248] at this time, It can be defined as follows.

[0249]

[0250] at this time, It can be defined as follows.

[0251] exist =8, ∈{1003, 1007}, When =6, it can be defined .

[0252] exist =8, ∈{1002,1006}, When =6, it can be defined .

[0253] exist =8, ∈{1001,1005}, When =6, it can be defined .

[0254] exist =8, ∈{1001, 1003, 1005, 1007}, When =12, it can be defined .

[0255] exist =8, ∈{1001, 1003, 1005, 1007}, =8, In this case, it can be defined .

[0256] exist =4, ∈{1001, 1003}, When =6, it can be defined .

[0257] exist =4, ∈{1001, 1003}, ∈{8,12}, In this case, it can be defined .

[0258] -In cases other than those mentioned above, it is possible to define .

[0259] at this time, It can be defined as follows.

[0260]

[0261] at this time, It can be defined as follows.

[0262]

[0263] k F ∈{0,1,…, P F -1} can be configured as the StartRBIndex for higher-level signaling, and k can be defined when it is not configured. F =0.

[0264] When configuring EnableStartRBHopping as a higher-layer signaling mechanism, it can be based on the following: and The value of k is determined by the following [Table 21]. hop And otherwise, k can be defined. hop =0.

[0265]

[0266] If SRS transmission is performed based on SRS-PosResource, then It can be defined based on [Table 22] below, and otherwise (if SRS transmission is performed based on onSRS-Resource), it can be defined =0.

[0267] n, as the offset value in the frequency dimension shift This determines the distance between the location where the SRS is transmitted and the reference location, and can be configured via freqDomainShift as a higher-layer signaling. The comb offset value can be configured via combOffset-n2, combOffset-n4, or combOffset-n8 within transmissionComb as higher-layer signaling. .

[0268] As a higher-level signaling related to SRS frequency hopping, b-hops within freqHoping can be configured, and b-hops can be defined. hop ∈{0,1,2,3}.

[0269] n b It is the value of the index indicating the frequency position, and can be defined as follows.

[0270] -If b hop ≥B SRS If SRS frequency hopping is not supported, the index n indicating the frequency position is used. b Can be found in all Each symbol has a constant value during its duration and is defined as follows.

[0271]

[0272] At this time, n RRC It is the value configured through freqDomainPosition as a higher-level signaling, and when n is not configured RRC At that time, the value can be 0.

[0273] -If b hop SRS ​Then SRS frequency hopping is supported, and n can be defined as follows: b .

[0274] If b≤b hop Then it can be defined .

[0275] Otherwise, it can be defined .

[0276] At this point, if N b It is an even number, F b (n) SRS ) can be defined as And if N b It is an odd number, F b (n) SRS ) can be defined as . It can be defined as 1, regardless of N. b What is the value of ?

[0277] n SRS This can be defined as a parameter that counts the number of SRS transmissions. If the UE sends aperiodic SRS resources, it can be in a specific time slot. Definition within a symbol At this point, when nrofSRS-Ports-n8, used as higher-level signaling, is configured as ports8tdm, s can be defined as s=2; otherwise, s=1 can be defined. In this case, R≤ This can be a value configured as the repetition factor for higher-level signaling, and when this value is not configured, R can be defined as... .

[0278] If the UE sends periodic or semi-persistent SRS resources, then it can meet the following conditions: In the time slot, n is defined as follows: SRS .

[0279]

[0280] At this time, T SRS and T offset These can refer to periodic or semi-persistent SRS periodicity and slot offset, respectively.

[0281] [Table 17]

[0282] [Table 18]

[0283] [Table 19]

[0284]

[0285] [Table 20]

[0286]

[0287] [Table 21]

[0288] [Table 22]

[0289] [Related to UE Capability Report]

[0290] In LTE and NR, a UE can execute a procedure to report the capabilities it supports to the corresponding BS while the UE is connected to the serving BS. In the following description, this is referred to as UE capability reporting.

[0291] The BS can send a UE capability query message requesting capability reports to a UE in a connected state. This message can include UE capability requests for each Radio Access Technology (RAT) type for the BS. Requests for each RAT type can include supported frequency band combination information, etc. Furthermore, in the case of a UE capability query message, the BS can request UE capabilities for each of multiple RAT types through a single RRC message container, or the BS can include multiple UE capability query messages containing UE capability requests for each RAT type and send them to the UE. That is, UE capability queries are repeated multiple times within a single message, and the UE can configure and report the corresponding UE capability information messages multiple times. In next-generation mobile communication systems, UE capability requests can be made for NR, LTE, E-UTRA-NR Dual Connectivity (EN-DC), and Multi-RAT Dual Connectivity (MR-DC). Moreover, while UE capability query messages are typically sent initially after the UE connects to the BS, they can be requested under any condition where the BS requires them.

[0292] During the aforementioned phases, the UE that receives a UE capability report request from the BS configures its capabilities based on the request received from the BS regarding RAT type and frequency band information. The methods for configuring UE capabilities in the NR system are summarized below.

[0293] 1. If the UE receives a list of LTE and / or NR frequency bands from the BS via a UE capability request, the UE configures a frequency band combination (BC) for EN-DC and NR Independent (SA). That is, the UE configures a candidate list of BCs for EN-DC and NR SA based on the requested frequency bands in the FreqBandList. Furthermore, the frequency bands have priorities as described in the FreqBandList.

[0294] 2. If the BS sets the “eutra-nr-only” flag or the “eutra” flag and requests a UE capability report, the UE will be completely removed from the configured BC candidate list. This type of operation can only be generated when the LTE base station (eNB) requests the “eutra” capability.

[0295] 3. Subsequently, the UE removes the backed-up BC from the BC candidate list configured in the above stage. A backed-up BC is a BC obtained by removing the frequency band corresponding to at least one SCell from the predetermined BCs, and the BCs prior to removing the frequency band corresponding to at least one SCell can cover the backed-up BC, and therefore the backed-up BC can be omitted. This stage applies to MR-DC, i.e., the LTE frequency band. The remaining BCs after this stage correspond to the final "candidate BC list".

[0296] 4. The UE selects a BC suitable for the requested RAT type from the final "Candidate BC List" and chooses the BC to be reported. During this stage, the UE configures the supportedBandCombinationList according to a predetermined order. That is, the UE configures the BCs to be reported and UE capabilities according to the preset RAT type order (NR->EUTRA-NR->EUTRA). Furthermore, the UE configures featureSetCombinations for the configured supportedBandCombinationList and configures a "Candidate Feature Set Combination" list in the candidate BC list, removing fallback BCs (including capabilities at the same or lower levels) from the candidate BC list. The "Candidate Feature Set Combination" can include all feature set combinations for NR and EUTRA-NR BCs and can be obtained from the feature set combinations in the UE-NR-Capabilities and UE-MRDC-Capabilities containers.

[0297] 5. Furthermore, when the requested rat type is eutra-nr and has an impact, featureSetCombinations are included in both containers of UE-MRDC-Capabilities and UE-NR-Capabilities. However, the NR feature set only includes UE-NR-Capabilities.

[0298] After configuring UE capabilities, the UE sends a UE capability information message, including the UE's capabilities, to the BS. Based on the UE capabilities received from the UE, the BS then performs scheduling, transmission, and reception management appropriate for the corresponding UE.

[0299] Referring to the above descriptions of SRS resource (set) related configurations and SRS antenna port configurations, operations considering up to four antenna ports for the BS and UE have been proposed. Specifically, operations for configuring SRS resources or SRS resource sets in the RRC configuration of the BS and UE can be configured based on the number of antenna ports using parameters (e.g., srs-ResourceID, nrofSRS-Ports, transmissionComb, combOffset, cyclicShift, resourceMapping, startPosition, nrofSymbols, repetitionFator, freqDomainPosition, FreqDomainShift, freqHopping, groupOrSequenceHopping, resourceType, sequenceID, spatialRelationInfo, etc.).

[0300] This design approach does not consider electronic devices supporting three transmit antenna ports. Furthermore, the SRS antenna port switching operation considered across a maximum of four antenna ports is not optimized for SRS resource configuration for three transmit antenna ports, resulting in limited performance when performing downlink channel estimation.

[0301] To overcome this degradation, three uplink transmit (Tx) antenna ports will be discussed in rel-19. Specifically, for electronic devices supporting 3 Tx, a method is required for the BS to configure SRS resources and / or SRS resource sets. Therefore, through embodiments of this disclosure, a method is proposed for configuring SRS resources and / or SRS resource sets to support three uplink transmit (Tx) antenna ports. Furthermore, various embodiments of this disclosure propose parameters that need to be added or expanded during the BS's SRS resource configuration process.

[0302] The operation of a BS and electronic device supporting multiple SRS ports is described below through detailed descriptions of various embodiments.

[0303] In this disclosure, a BS is an entity that allocates resources to electronic devices and can be at least one of a gNode B, gNB, eNodeB, Node B, base station (BS), radio access unit, BS controller, and nodes in a network. Electronic devices may include terminals, user equipment (UE), mobile stations (MS), cellular phones, smartphones, computers, multimedia systems capable of performing communication functions, CPEs, FWAs, vehicles, industrial equipment, etc. Electronic devices may support three or more Tx antenna ports.

[0304] <First Implementation Example: UE Capability Report for a UE Supporting Three Transmit Antennas>

[0305] The following describes in detail, through various embodiments, a method for sending a detailed UE capability report message to the BS related to the support capabilities of the three transmit antennas.

[0306] As an example, for a UE that supports three transmit antennas, the FeatureSetUplink message may include at least one antenna switching related information. Here, the antenna switching related information may include various parameter information considering "3T4R", "3T6R", and "3T8R".

[0307] As an example, for SRS transmission based on three transmit antennas, the UE may include information in its parameter information regarding the possibility of supporting resources for configuring two semi-persistent SRS transmissions and resources for configuring one periodic SRS transmission during antenna switching (e.g., srs-AntennaSwitching2SP-1Periodic-r19). The BS receives the UE's message and configures the resources so that the UE can transmit at least two semi-persistent SRS signals and one periodic SRS signal. As another example, the UE may include in its parameter information the possibility of supporting resources for configuring at least one aperiodic (non-persistent) SRS transmission during antenna switching (e.g., srs-ExtensionAperiodicSRS-r19) for SRS transmission based on three transmit antennas. The BS receives the UE's message and configures the resources so that the UE can transmit at least one aperiodic SRS signal.

[0308] The following describes in detail a method for sending a UE capability report message to the BS about detailed band pairs and delay times by combining the three transmit antenna support capabilities.

[0309] The UE can send a detailed capability report message to the BS, incorporating the handover delays of the three transmit antennas. Table 23 shows the message formats for band combination (BandCombination-UplinkTxSwitch-v1900), band pair (ULTxSwitchingBandPair), and specific band parameters (UplinkTxSwitchingBandParameters) used for handover during uplink transmissions. Here, uplink transmission scenarios can include PUSCH transmissions and SRS transmissions.

[0310] [Table 23]

[0311] BandCombination-UplinkTxSwitch allows you to specify the band combinations supported by the UE for uplink transmission handover. For each supported band pair (SupportedBandPairList) from the band combination, the UE can specify whether it supports the switched uplink operating mode (switchedUL), dual operating mode (dualUL), or both. For each band pair (ULTxSwitchingBandPair), the UE can also specify timing information (uplinkTxSwitchingPeriod) by the handover between the bands (bandIndexUL1, UL2) that the UE can switch (e.g., the time taken to switch a power amplifier from one band to another).

[0312] As an embodiment, during operation using three transmit antennas in the first frequency band, the UE can specify the time spent switching to the second frequency band while maintaining the same number of transmit antennas, according to its capabilities. In a specific example, the value of the timing information for the switch can be specified as at least one of n35us, n70us, n140us, n210us, and n280us. As another embodiment, during operation using three transmit antennas in the first frequency band, the UE can specify the time spent switching to the second frequency band while changing a different number (e.g., 1 or 2) of transmit antennas, according to its capabilities. In a specific example, the value of the timing information for the switch can be specified as at least one of n35us, n70us, n140us, n210us, and n280us. As yet another embodiment, during operation using one or two transmit antennas in the first frequency band, the UE can specify the time spent switching to the second frequency band while changing all three transmit antennas, according to its capabilities. In a specific example, the value of the timing information for the switch can be specified as at least one of n35us, n70us, n140us, n210us, and n280us.

[0313] <Second Embodiment: Method for Determining Antenna Ports for a UE Supporting Three Transmit Antennas>

[0314] The following describes a detailed method for a UE supporting three transmit antennas to determine the antenna ports through various embodiments.

[0315] When configuring SRS resources to support a UE with three transmit antennas, the antenna ports can be determined based on SRS sequence generation and physical resource mapping. Specifically, the BS can configure cyclic shift values ​​and comb offset values ​​to configure three SRS antenna ports in the UE. The UE can use the cyclic shift values ​​during the SRS sequence generation phase and the comb offset values ​​during the resource mapping phase to transmit SRS in the allocated time and frequency resources (SRS resources).

[0316] The UE and BS can assume that the antenna ports associated with the SRS transmitted by the UE and the PUSCH antenna ports that the BS can schedule based on the SRS transmitted by the UE are the same, and therefore, a method can be considered to minimize the impact on the standard by substantially modifying some of the four already determined transmit antenna ports. In the following embodiments, to determine the SRS antenna ports, it is assumed that the BS substantially configures three or four SRS resources in the UE in the RRC and determines three SRS antenna ports therein.

[0317] As an example, when four PUSCH antenna ports are indicated as 1000, 1001, 1002 and 1003, and SRS resources and three SRS antenna ports are indicated, the BS and UE can consider and determine that the first antenna port 1000 is not transmitted for the determination of the SRS antenna ports.

[0318] As an example, when four PUSCH antenna ports are designated as 1000, 1001, 1002 and 1003, and SRS resources and three SRS antenna ports are configured, the BS and UE can consider and determine that the last antenna port 1003 is not sent to determine the SRS antenna port.

[0319] As an example, when four PUSCH antenna ports are designated as 1000, 1001, 1002, and 1003, and SRS resources and three SRS antenna ports are indicated, the BS and UE can determine a number for the SRS antenna ports based on RRC configuration, MAC CE messages, or at least one DCI message to identify the SRS antenna ports and non-transmitting SRS antenna ports. For example, when at least one message corresponding to antenna port 1002 is identified based on this information, the UE can assume that antenna port 1002 is not being transmitted and determine the remaining SRS antenna ports corresponding to 1000, 1001, and 1003.

[0320] As an example, when four PUSCH antenna ports are indicated as 1000, 1001, 1002, and 1003, and SRS resources and three SRS antenna ports are indicated, if the comb (K) in Table 16 TC The maximum cyclic shift value is 2 and is used in the RRC configuration for determining the SRS antenna port and the non-transmit SRS antenna port. If configured to 8, the BS and UE can determine the comb offset value ( The UE determines whether the number of antenna ports is even or odd, and if it is even, it considers that the last antenna port 1003 will not be transmitted, and if it is odd, it considers and determines that the first antenna port 1000 will not be transmitted. Conversely, under the same conditions, the UE can assume that the first antenna port 1000 will not be transmitted if the number of antenna ports is even, and determines that the first antenna port 1003 will not be transmitted if the number of antenna ports is odd.

[0321] As an example, when four PUSCH antenna ports are indicated as 1000, 1001, 1002, and 1003, and SRS resources and three SRS antenna ports are indicated, the BS and UE can determine the non-transmit antenna port based on the comb offset value and cyclic shift value in Table 16 of the RRC configuration used to determine the SRS antenna port and the non-transmit SRS antenna port. Specifically, the UE can determine the non-transmit antenna port based on the configured comb offset value ( The antenna port corresponding to the minimum value (e.g., 0) and the maximum value (e.g., 0) of the cyclic shift value is not transmitted. Conversely, under the same conditions, the UE can determine the configuration of the comb offset value ( The antenna ports corresponding to the maximum value (e.g., 1) and the maximum value of the cyclic shift (e.g., 8) are not transmitted.

[0322] As described above, various embodiments consider minimizing noise or interference between SRS signals transmitted by UEs scheduled by the BS.

[0323] Furthermore, in the above embodiments, when the port numbers of the antenna ports constituting the SRS antenna port are 1000, 1001, and 1002, and the port numbers of the antenna ports constituting the PUSCH antenna port are 1000, 1001, and 1002, the connection relationship / correlation between the SRS antenna port and the PUSCH antenna port can be maintained.

[0324] Alternatively, when the port numbers of the antenna ports constituting the SRS antenna port are 1001, 1002, and 1003, and the port numbers of the antenna ports constituting the PUSCH antenna port are 1000, 1001, and 1002, the connection relationship between the SRS antenna port and the PUSCH antenna port is not maintained. Instead, the sequential sequence can be maintained similarly (e.g., SRS 1001-PUSCH1000, SRS 1002-PUSCH 1001, SRS 1003-PUSCH 1002).

[0325] Alternatively, when the port numbers of the antenna ports constituting the SRS antenna port are 1001, 1002, and 1003, and the port numbers of the antenna ports constituting the PUSCH antenna port are 1000, 1001, and 1002, the SRS antenna port numbers can be readjusted to match the PUSCH antenna numbers to maintain the connection between the SRS and PUSCH antenna ports. In embodiments such as those described above, there is an advantage in minimizing the impact of standard changes.

[0326] The various embodiments described below can operate based on at least one of the various embodiments of the SRS antenna port configuration, and it can be assumed that these embodiments can be fully considered even if details are omitted.

[0327] <Third Embodiment: SRS Resource Configuration for Supporting Antenna Switching of a UE with Three Transmit Antennas>

[0328] The following describes a detailed method for configuring SRS resources to support antenna switching for a UE with three transmit antennas, through detailed descriptions of various embodiments.

[0329] The BS can configure resources to send uplink probe signals (SRS) to the UE to improve downlink throughput. In the following embodiments, SRS resources configured in the UE taking into account a maximum of three transmit antennas and y (e.g., 4, 6, or 8) receive antennas are described. These configured resources are set up in the UE by the BS via an RRC message and are configured to perform antenna switching operations.

[0330] As an example, the BS can configure separate SRS resources and SRS resource sets in the UE for antenna handover. Specifically, a UE configured to transmit from the BS using up to three antennas can receive configurations of at least one type: periodic, semi-persistent, and aperiodic as the SRS resource type. For example, for periodic and semi-persistent SRS resource configurations, the number of SRS resource sets can be configured to 0 or 1, and for aperiodic SRS resource configurations, the number of SRS resource sets can be configured to 0 to 2. Here, an SRS resource set may include four SRS resources transmitted in different symbols. In another example, for periodic and semi-persistent SRS resource configurations, the number of SRS resource sets can be configured to 0 or 1, and for aperiodic SRS resource configurations, the number of SRS resource sets may be configured to 0 to 4. Here, an SRS resource set may include four SRS resources transmitted in different symbols.

[0331] As an example, the SRS resources configured by the BS in the UE can be configured to a maximum of 16 per BWP, and the number of configured SRS resources can be configured according to the type of non-periodic / periodic / semi-persistent SRS resources. Specifically, the number of SRS resources configured in the UE for each BWP can be determined as a value among {1, 2, 4, 8, 16}. Furthermore, the number of SRS resources configured in the UE for each BWP in each time slot can be determined as a value among {1, 2, 3, 4, 5, 6}. Additionally, the maximum number of SRS ports configured in the UE for each resource can be determined as a value among {1, 2, 3, 4}. Furthermore, the list of transmit and receive pairs (Tx-Rx pairs) supporting SRS Tx port switching configured in the UE can be determined as one of {“Not supported”, “3T4R”, “3T3R”, “3T6R”, “3T8R”}.

[0332] As an example, the UE can report to the BS whether the uplink handover operation of SRS and PUSCH affects downlink reception in a specific frequency band, and whether a handover is also performed in another frequency band when the uplink handover of SRS and PUSCH is performed in a specific frequency band.

[0333] As an example, the BS can instruct the UE to first maintain the value of the parameter "nrofSRS-Ports" related to the number of antenna ports used for SRS transmission at 4, and then configure three ports during the RRC configuration phase using separate signaling. In another example, the BS can configure the value of the parameter "nrofSRS-Ports-n3-r19" related to the number of antenna ports used for SRS transmission in the UE to 3 during the RRC configuration phase.

[0334] <Fourth Embodiment: A Method for SRS Antenna Switching of a UE Supporting y Receive Antennas and Three Transmit Antennas>

[0335] The following describes a detailed method for switching antennas for a UE supporting y receive antennas and three transmit antennas, through various embodiments. The SRS antenna switching operation for a UE supporting three transmit antennas can take into account the maximum number of receive antennas reported by the UE to the BS.

[0336] When a UE capability report indicating that it supports 3TyR (three transmit antennas and y receive antennas) is received, the BS can configure SRS resources, SRS resource sets, and SRS resource types (e.g., periodic, semi-persistent, and aperiodic) for UEs that include 3TyR. In the embodiments of this disclosure, examples of the case where y=4 are primarily described; however, this is merely an example for ease of description and does not limit the scope of this disclosure. Furthermore, this disclosure can be applied to cases where y is configured to another value.

[0337] First, in the embodiments, embodiments are described that minimize SRS resource intervals and periodicity as much as possible to improve performance through reduced resource allocation.

[0338] Figure 6a Examples of SRS resource configuration and Tx / Rx antenna port mapping in SRS antenna switching considering 3T4R according to embodiments of the present disclosure are shown.

[0339] refer to Figure 6a The UE can perform mapping so that the antenna port of a UE supporting 3T4R capability corresponds to the SRS antenna port.

[0340] For example, the BS can configure two SRS resources for three transmit antennas in the UE, or it can configure at least one SRS resource set including two SRS resources. Furthermore, as in the fourth embodiment described above, the BS can configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) for specifying the three SRS antenna ports in the first SRS resource configuration, and specify antenna ports that are the same as or partially different from the first SRS resource, so that the three SRS antenna ports can be specified in the second SRS resource.

[0341] When the higher-layer parameter "usage" is configured as "antenna switching", the UE can use the mapping between the UE's internal receiving antenna and the SRS antenna port indicated by the BS to perform SRS transmission.

[0342] As shown in Table 24, when SRS antenna ports 0, 1, and 2 are configured in the first SRS resource, the UE can map its transmit / receive antenna ports 0, 1, and 2 to transmit SRS signals. Furthermore, when SRS antenna ports 0, 1, and 2 are configured in the second SRS resource, the UE can map its transmit / receive antenna ports 1, 2, and 3 to transmit SRS signals. As described above, the BS and UE can transmit SRS signals using an antenna consisting of three different transmit antenna sets out of four receive antennas, thus allowing 3T4R-enabled UEs to later determine a better antenna set.

[0343] [Table 24]

[0344] In the above description, an embodiment in which the SRS antenna port numbers indicated for the first SRS resource and the second SRS resource are respectively indicated as {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2} has been described. However, embodiments in which some different antenna ports are explicitly indicated can be similarly applied and extended, such that the SRS antenna port numbers indicated for the first SRS resource are {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2}, and the SRS antenna port numbers indicated for the second SRS resource are {SRS antenna port 1, SRS antenna port 2, SRS antenna port 3}.

[0345] Second, in the embodiments, an example is shown that maximizes the SRS resource interval and periodicity as much as possible to find the optimal set of transmit and receive antennas through heavy resource allocation.

[0346] Figure 6b Another example of an antenna port configured in an SRS resource in consideration of 3T4R SRS antenna switching is shown in accordance with the description of embodiments of the present disclosure.

[0347] refer to Figure 6b The UE can perform mapping so that the antenna port of a UE supporting 3T4R capability corresponds to the SRS antenna port.

[0348] For example, the BS can configure a total of four SRS resources for the three transmit antennas in the UE, or it can configure at least one SRS resource set including four SRS resources. Furthermore, as in the second and third embodiments described above, the BS can configure (i) various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) for specifying three SRS antenna ports in the first SRS resource, (ii) parameters for specifying three SRS antenna ports with at least one antenna port number different from the first SRS resource in the second SRS resource, (iii) parameters for specifying three SRS antenna ports with at least one antenna port number different from the first and second SRS resources in the third SRS resource, and (iv) parameters for specifying three SRS antenna ports with at least one antenna port number different from the first to third SRS resources in the fourth SRS resource.

[0349] For example, when the higher-layer parameter “usage” is configured as “antenna switching”, at least one SRS resource set including four SRS resources is configured, and the value of “nrofSRS-Ports-n3-r19” is configured as 3, the UE can use the correspondence between the UE’s internal receiving antenna and the SRS antenna port mapping indicated by the BS to perform SRS transmission.

[0350] As shown in Table 25, when SRS antenna ports {0,1,2} are configured in the first SRS resource, the UE can map its transmit / receive antenna ports {0,1,2} to transmit SRS signals. When SRS antenna ports {0,1,2} are configured in the second SRS resource, the UE can map its transmit / receive antenna ports {0,1,3} to transmit SRS signals. When SRS antenna ports {0,1,2} are configured in the third SRS resource, the UE can map its transmit / receive antenna ports {0,2,3} to transmit SRS signals. When SRS antenna ports {0,1,2} are configured in the fourth SRS resource, the UE can transmit SRS signals through the mapping operation of its transmit / receive antenna ports {1,2,3}. As a result, the UE can use three of the four receive antenna ports.

[0351] [Table 25]

[0352] Third, in the embodiments, an example is shown that maximizes the SRS resource interval and periodicity as much as possible to find the optimal set of transmit and receive antennas through heavy resource allocation.

[0353] The UE can perform mapping so that the antenna port of the 3T4R UE corresponds to the SRS antenna port. This embodiment introduces a scheme for updating some information in the information previously configured in the RRC.

[0354] For example, the BS can configure two SRS resources for four transmit antennas in the UE, or configure at least one SRS resource set including two SRS resources. Furthermore, as in the fourth embodiment described above, the BS can configure various parameters (e.g., SRS resources, transmission type, comb, cyclic shift, etc.) for specifying the four SRS antenna ports in the first SRS resource configuration, and configure the same antenna ports in the second SRS resource as the first SRS resource for specifying the four SRS antenna ports.

[0355] When the higher-layer parameter "usage" is configured as "antenna switching", the UE can use the mapping between the receiving antenna in the UE and the SRS antenna port indicated by the BS to perform SRS transmission.

[0356] When SRS antenna ports 0, 1, 2, and 3 are configured in the first and second SRS resources, the UE can first sequentially map its transmit / receive antenna ports 0, 1, 2, and 3. After mapping, the UE can choose not to transmit antenna ports based on information indicated by the BS or a predetermined pattern. For example, the indicated information may include information related to non-transmit SRS or PUSCH antenna ports (e.g., number 3 (no. 3)) or pattern information for non-transmit antenna ports (e.g., {3,1}). As a result, the UE can perform a two-stage operation that reflects some updated information in the pre-configured resource and antenna port information without significantly modifying the existing four SRS antenna port configuration information to perform a 3T4R SRS antenna handover operation.

[0357] Figure 6c Another example of an antenna port configured in an SRS resource in SRS antenna switching considering 3T4R is shown according to an embodiment of the present disclosure.

[0358] refer to Figure 6c The UE can perform mapping so that the antenna port of the 3T4R UE corresponds to the SRS antenna port. This embodiment introduces a scheme to update some information in the information previously configured in the RRC.

[0359] For example, the BS can configure a total of four SRS resources for three transmit antennas in the UE, or configure at least one SRS resource set including four SRS resources.

[0360] The BS can configure various parameters (e.g., SRS resources, transmission type, comb, cyclic shift, etc.) in the first to fourth SRS resource configurations in the UE to specify the four SRS antenna ports.

[0361] For example, when the higher-layer parameter "usage" is configured as "antenna switching", at least one SRS resource set including four SRS resources is configured, and the value of "nrofSRS-Ports-n3-r19" is configured as 3, the UE can perform SRS transmission using the correspondence between the UE's receive antenna and the SRS antenna port mapping indicated by the BS. When SRS antenna ports {0, 1, 2, 3} are configured in the first to fourth SRS resources, the UE can sequentially map the UE's transmit / receive antenna ports {0, 1, 2, 3}. After mapping, the UE can choose not to transmit antenna ports based on information indicated by the BS or a predetermined pattern. For example, the indicated information may be related to non-transmit SRS or PUSCH antenna ports (e.g., number 3), or may include pattern information for non-transmit antenna ports (e.g., identifiers corresponding to 3→2→1→0). As a result, the UE can perform a two-stage operation that reflects some updated information in the pre-configured resource and antenna port information without significantly modifying the existing four SRS antenna port configuration information to perform a 3T4R SRS antenna switching operation.

[0362] Fourth, in the embodiments, an embodiment is shown that improves performance by taking into account the SRS resource allocation of both 3T4R and 1T4R.

[0363] Figure 7a An example of SRS resource configuration for SRS antenna switching and Tx / Rx antenna port mapping in SRS antenna switching considering 3T4R is shown according to an embodiment of the present disclosure.

[0364] refer to Figure 7a The UE can perform mapping so that the antenna port of a UE supporting 3T4R capability corresponds to the SRS antenna port.

[0365] For example, the BS can configure an SRS resource set in the UE, including a total of four SRS resources for three transmit antennas and four SRS resources for one transmit antenna. Furthermore, similar to the second and third embodiments described above, the BS can configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the first SRS resource to specify the three SRS antenna ports, and configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the second SRS resource to specify one SRS antenna port. Subsequently, the BS can configure parameters in the third SRS resource to specify three SRS antenna ports having at least one antenna port different from the first SRS resource, and configure parameters in the fourth SRS resource to specify one SRS antenna port different from the second SRS resource. The BS can configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the fifth SRS resource to specify three SRS antenna ports having at least one antenna port different from the first and third SRS resources, and configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the sixth SRS resource to specify one SRS antenna port different from the second and fourth SRS resources. Subsequently, the BS can configure parameters in the seventh SRS resource to specify three SRS antenna ports having at least one antenna port different from the first, third, and fifth SRS resources, and configure parameters in the eighth SRS resource to specify one SRS antenna port different from the second, fourth, and sixth SRS resources. As described above, by configuring an SRS resource set including eight SRS resources, the BS can alternately select three of the four receive antennas in the odd-numbered resources for the UE, and alternately select and transmit one antenna other than the aforementioned three receive antennas in the even-numbered resources, in order to periodically, semi-persistently, and aperiodically measure SRS performance based on 3T and 1T according to the transmission type.

[0366] For example, when the higher-layer parameter "usage" is configured as "antenna switching," and at least one SRS resource set including 8 SRS resources is configured, with the value of "nrofSRS-Ports-n3-r19" set to 3 in 4 of the 8 SRS resources and the value of "nrofSRS-Ports-n3-r19" set to 1 in the remaining 4 SRS resources, the UE can use the mapping relationship between the UE's receiving antenna and the SRS antenna port indicated by the BS to perform SRS transmission. When SRS antenna ports {0,1,2} are configured in the first SRS resource, the UE can map its transmit / receive antenna ports {0,1,2} to transmit SRS signals. When the third SRS antenna port {0,1,2} is configured, the UE can map its transmit / receive antenna ports {0,1,3} to transmit SRS signals. When the fifth SRS antenna port {0,1,2} is configured, the UE can map its transmit / receive antenna ports {0,2,3} to transmit SRS signals. When the seventh SRS antenna port {0,1,2} is configured, the UE can transmit SRS signals through the mapping operation of the UE's transmit / receive antenna ports {1,2,3}. As a result, the UE can use three of the four receive antenna ports. Furthermore, when SRS antenna ports {0} or {3} are configured in the second SRS resource, the UE can map the UE's transmit / receive antenna port {3} to transmit SRS signals. When the fourth SRS antenna port {0} or {2} is configured, the UE can map the UE's transmit / receive antenna port {2} to transmit SRS signals. When the sixth SRS antenna port {0} or {1} is configured, the UE can map the UE's transmit / receive antenna port {1} to transmit SRS signals. When the eighth SRS antenna port {0} is configured, the UE can transmit SRS signals through the mapping operation of the UE's transmit / receive antenna port {0}. As a result, the UE uses the four receive antennas in a cyclical manner, one at a time.

[0367] In the above Figure 7a In the embodiments described, an SRS resource set comprising a total of eight SRS resources has been described; however, the BS can configure an SRS resource set to include, for example... Figure 7b The disclosure includes a total of four SRS resources to reduce resource waste and transmission periodicity, and those skilled in the art will fully understand that this disclosure is similarly configured and operated even without detailed description.

[0368] Figure 7b Another example of an antenna port configured in an SRS resource considering 3T4R SRS antenna switching, as described in the embodiments of this disclosure, is shown. (See also: References) Figure 7bFor example, when the higher-layer parameter "usage" is configured as "antennaswitching", and at least one SRS resource set including four SRS resources is configured, with the value of "nrofSRS-Ports-n3-r19" configured as 3 in two of the four SRS resources and the value of "nrofSRS-Ports-n3-r19" configured as 1 in the remaining two SRS resources, the UE can use the mapping relationship between the receiving antenna within the UE and the SRS antenna port indicated by the BS to perform SRS transmission. When SRS antenna ports {0,1,2} are configured in the first SRS resource, the UE can map the UE's transmit / receive antenna ports {0,1,2} to transmit SRS signals. When the third SRS antenna port {0,1,2} is configured, the UE can map the UE's transmit / receive antenna ports {0,1,3} to transmit SRS signals. Furthermore, when SRS antenna ports {0} or {3} are configured in the second SRS resource, the UE can map the UE's transmit / receive antenna port {3} to transmit SRS signals. When the fourth SRS antenna port {0} or {2} is configured, the UE can map the UE's transmit / receive antenna port {2} to transmit SRS signals.

[0369] Fifth, in the embodiments, an embodiment is shown in which performance is improved by the SRS resource allocation of the UE when the BS is configured to operate at 3T in one uplink carrier and at 1T to 3T in at least one remaining carrier.

[0370] Figure 8 Another example of an antenna port configured in an SRS resource during carrier aggregation operation in an SRS antenna switching operation taking into account 3T4R is shown according to an embodiment of the present disclosure.

[0371] For example, refer to Figure 8 The BS can configure a first SRS resource set in the UE, which includes a total of four SRS resources for three transmit antennas, and another second SRS resource set, which includes four SRS resources for at least one transmit antenna, in an uplink carrier.

[0372] Furthermore, as in the second and third embodiments described above, the BS can configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the first SRS resource of the first uplink carrier for specifying three SRS antenna ports, parameters for specifying three SRS antenna ports having at least one antenna port different from the first SRS resource in the second SRS resource, parameters for specifying three SRS antenna ports having at least one antenna port different from the first and second SRS resources in the third SRS resource, and parameters for specifying three SRS antenna ports having at least one antenna port different from the first to third SRS resources in the fourth SRS resource.

[0373] In addition, the BS can configure various parameters (e.g., SRS resource, transmission type, comb, cyclic shift, etc.) in the first SRS resource of the second uplink carrier to specify one to three SRS antenna ports, parameters to specify one to three SRS antenna ports with at least one antenna port different from the first SRS resource in the second SRS resource, parameters to specify one to three SRS antenna ports with at least one antenna port different from the first and second SRS resources in the third SRS resource, and parameters to specify one to three SRS antenna ports with at least one antenna port different from the first to third SRS resources in the fourth SRS resource.

[0374] Here, in the case of inter-band combinations with a large frequency difference between the first and second uplinks, the UE can configure separate gaps in terms of the timing of SRS transmissions for the first and second uplinks. Specifically, the size of the gap can be configured based on switching elements in the SRS antenna transmitted in the first carrier and changing them to the shortest time suitable for the second carrier.

[0375] Meanwhile, for a serving cell with a time slot format configured by DL and UL symbols but not configured for PUSCH / PUCCH transmission, if signaled by the higher-layer parameters srs-SwitchFromServCellIndex and srs-SwitchFromCarrier, when the carrier corresponding to the serving cell whose UL transmission is temporarily suspended is c2, the set S(c2) = {c2, S1(c2), ..., S...} N-1 (c2)} is defined as the set of carriers of the serving cell that each carrier satisfies one of the following conditions.

[0376] S i (c2) Within the same frequency band and the same timing advance group (TAG) as c2. S i(c2) is a carrier with inter-band CA having c2, and S i (c2) The SRS-SwitchingAffectedBandsListNR capability signaling is expressed as being affected by the SRS handover from c2 to c1. Here, 1≤i≤N-1.

[0377] For symbols on carrier c1 For SRS transmissions starting at a given point and conflicting transmissions starting at a random carrier within set S(c2), the UE may consider the following when applying priority determination / drop rules.

[0378] DCI, which is the last symbol of the PDCCH at the start of the SRS transmission. The time interval between them is at least N² symbols plus an additional duration. And the last symbol of PDCCH is N S The time interval between them is at least N² symbols; and

[0379] It can be considered that semi-persistent CSI reports or SRS are in It is activated for at least N2 symbols prior to the additional duration T_(SRS_CS), and in N S It was activated during the previous N2 symbol period.

[0380] here, =max{ switchingTimeUL, switchingTimeDL Furthermore, the time interval unit of the OFDM symbol is calculated based on the set S(c2), c1 and the smaller subcarrier interval on the random carrier in the corresponding scheduling cell.

[0381] here, switchingTimeUL The time can be determined based on whether the port used in the corresponding carrier is used for partial overlap or non-overlap in the same time slot and the predetermined number of symbols in carrier c1 of the serving cell supported by the UE, as at least one of the following values: {n0us, n30us, n100us, n140us, n200us, n300us, n500us, n900us}, which can be reported by the UE to the BS.

[0382] <Fifth Implementation Example: UE detection procedure based on whether the UE supporting 3T4R supports SRS-AntennaSwitching2SP-1Periodic, SRS-ExtensionAperiodicSRS>

[0383] The following describes, through detailed descriptions of various embodiments, UE probe procedures based on whether a UE supporting four receive antennas and three transmit antennas supports a semi-persistent or aperiodic specific SRS combination.

[0384] The BS can basically configure zero or one SRS resource set in the UE, where the resourceType of the SRS-ResourceSet is configured as "periodic". Here, in the case of one resource set, two SRS resources can be transmitted in different symbols, and each SRS resource of a given set can consist of three SRS ports.

[0385] Furthermore, the SRS ports of resources within an SRS resource set can be associated with a pair or a group of different UE antenna ports, and the BS can configure zero or one SRS resource set in the UE. When the UE does not report srs-AntennaSwitching2SP-1Periodic, the BS can configure the resourceType of the SRS-ResourceSet as "semi-persistent" in the UE.

[0386] Alternatively, for 0, 1, 2, or 4 SRS resource sets, the BS can configure the ResourceType of the SRS-ResourceSet to "aperiodic" in the UE. In this case, during the UE configuration operation... 1) When a resource set has two or four SRS resources transmitted in different symbols, each SRS resource in a given set can consist of three SRS ports, and the set of SRS ports corresponding to the resource (e.g., three SRS ports) can be associated with different UE antenna port sets.

[0387] 2-1) When two SRS resources of two resource sets are transmitted in different symbols of two different time slots, the SRS port set of each SRS resource of the two given sets can be associated with different UE antenna ports. One resource set can consist of one SRS resource, and the other resource set can consist of one resource.

[0388] 2-2) When a total of four SRS resources for two resource sets are transmitted in different symbols of two different time slots, the SRS port set for each SRS resource of the two given sets can be associated with different UE antenna port sets. One set can consist of two SRS resources, and the other set can also consist of two SRS resources.

[0389] 3) In the case of four SRS resource sets, a total of four SRS resources can be transmitted in different symbols in four different time slots, and the SRS port set of each SRS resource in the four given sets can be associated with a different UE antenna port set.

[0390] Conversely, when the UE reports the "srs-AntennaSwitching2SP-1Periodic" parameter and the UE only indicates srs-AntennaSwitching2SP-1Periodic, the BS can configure up to two semi-persistent resource sets and up to one periodic resource set, but cannot activate two semi-persistent resource sets simultaneously.

[0391] A BS can configure a maximum of two SRS resource sets, with different values ​​configured for the high-level parameter resourceType of SRS-ResourceSet. Furthermore, two SRS resource sets configured as "semi-persistent" cannot be activated simultaneously.

[0392] The BS can configure up to two SRS resource sets configured as "semi-persistent" and up to one SRS resource set configured as "periodic" in the UE, and the two SRS resource sets configured as "semi-persistent" cannot be active at the same time. Each SRS resource set can have two SRS resources transmitted in different symbols, each SRS resource in a given set can consist of three SRS ports, and the SRS ports of the resources within the set can be associated with different UE antenna port sets.

[0393] Meanwhile, when the UE reports the "srs-ExtensionAperiodicSRS" parameter, as an example, the BS can configure up to two SRS resource sets with the resourceType of the SRS-ResourceSet configured as "aperiodic", and up to one SRS resource set with the resourceType of the SRS-ResourceSet configured as "periodic" or "semi-persistent".

[0394] As another embodiment, when the UE reports the "srs-ExtensionAperiodicSRS" parameter, the BS can configure up to two SRS resource sets, with different values ​​configured for the higher-level parameter resourceType of the SRS-ResourceSet.

[0395] For example, when two SRS-ResourceSets are configured with resourceType set to "aperiodic", a total of two SRS resources can be transmitted in different symbols of two different time slots, and each SRS resource in the two given sets can consist of three SRS ports. Furthermore, the SRS ports of the SRS resources within each set can be associated with different UE antenna port sets, and each of the two sets can consist of one SRS resource.

[0396] For example, when a resource set is configured with its SRS-ResourceSet resourceType configured as "aperiodic", a total of two SRS resources can be transmitted in different symbols within the same time slot. Each SRS resource in a given set can consist of three SRS ports, and the three SRS ports of the second resource can be associated with the three SRS ports of the first resource and different UE antenna port pairs.

[0397] For example, when configuring a resource set in an SRS-ResourceSet with "resourceType" set to "periodic" or "semi-persistent", two SRS resources can be configured to be transmitted in different symbols, and each SRS resource in a given set can consist of three SRS ports. The SRS ports of the second resource can be associated with the three SRS ports of the first resource and different UE antenna port sets.

[0398] As another embodiment, the BS can configure up to four SRS resource sets in the UE, each with a resourceType configured as a different type of SRS-ResourceSet.

[0399] For example, when the resourceType of all four SRS-ResourceSets is configured as "aperiodic", the UE can transmit SRS signals in different symbols of four different time slots using a total of four SRS resources. In this case, each SRS resource within the four given sets can be associated with three SRS ports. Here, the SRS resources can have different UE antenna ports, and each of the four sets can consist of one SRS resource.

[0400] For example, when the resourceType of both SRS-ResourceSets is configured as "aperiodic", the UE can transmit SRS signals in different symbols of two different time slots using a total of four SRS resources. In this case, each SRS resource within the two given sets can be associated with three SRS ports. Here, SRS resources can be associated with different UE antenna ports, and each of the two sets can consist of two SRS resources.

[0401] For example, when an SRS-ResourceSet is configured with resourceType set as "aperiodic", the UE can transmit SRS signals in different symbols within the same time slot using a total of four SRS resources, and each SRS resource in a given set can consist of three SRS ports. In this case, the three SRS ports of the second resource can be associated with the three SRS ports of the first resource and different UE antenna port sets.

[0402] For example, when each SRS resource set in an SRS-ResourceSet is configured with "resourceType" set to "periodic" or "semi-persistent" and contains four SRS resources transmitted in different symbols, the UE can transmit SRS signals using these four SRS resources from different symbols. Furthermore, the UE can configure three SRS ports in each SRS resource of a given set; in this case, the three SRS ports of the second resource can be associated with the three SRS ports of the first resource and different sets of UE antenna ports.

[0403] <Sixth Embodiment: A Method for SRS Antenna Switching of a UE Supporting y Receive Antennas and Three Transmit Antennas>

[0404] Figure 9 Examples of SRS resource configuration and Tx / Rx antenna port mapping in SRS antenna switching considering 3T6R according to embodiments of the present disclosure are shown.

[0405] refer to Figure 9 The UE can perform mapping so that the antenna port of a UE supporting 3T6R capability corresponds to the SRS antenna port.

[0406] For example, the BS can configure two SRS resources for three transmit antennas in the UE, and configure at least one SRS resource set including the two SRS resources. Furthermore, as in the fourth embodiment described above, the BS can specify three antenna ports in the first SRS resource, and specify the same antenna ports as the first SRS resource or different antenna ports in the second SRS resource.

[0407] When the higher-layer parameter "usage" is configured as "antenna switching", the UE can use the mapping between the receiving antenna in the UE and the SRS antenna port indicated by the BS to perform SRS transmission.

[0408] As shown in Table 26, when SRS antenna ports 0, 1, and 2 are configured in the first SRS resource, the UE can map its transmit / receive antenna ports 0, 1, and 2 to transmit SRS signals. Furthermore, when SRS antenna ports 0, 1, and 2 are configured in the second SRS resource, the UE can map its transmit / receive antenna ports 3, 4, and 5 to antenna ports different from those used for transmitting SRS signals in the first SRS resource. As described above, the BS and UE can transmit SRS signals using an antenna consisting of three different transmit antenna sets out of six receive antennas, thus allowing 3T6R-enabled UEs to later determine a better antenna set.

[0409] [Table 26]

[0410] In the above description, an embodiment in which the SRS antenna port numbers indicated for the first SRS resource and the second SRS resource are respectively indicated as {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2} has been described. However, the embodiment in which different antenna ports are explicitly indicated can be similarly applied and extended, such that the SRS antenna port numbers indicated for the first SRS resource are {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2}, and the SRS antenna port numbers indicated for the second SRS resource are {SRS antenna port 3, SRS antenna port 4, SRS antenna port 5}.

[0411] Figure 10 Examples of SRS resource configuration and Tx / Rx antenna port mapping in SRS antenna switching considering 3T8R are shown according to embodiments of the present disclosure.

[0412] refer to Figure 10 The UE can perform mapping so that the antenna port of a UE supporting 3T8R capability corresponds to the SRS antenna port.

[0413] For example, the BS can configure two SRS resources for three transmit antennas in the UE, or configure at least one SRS resource set including two SRS resources. Furthermore, as in the fourth embodiment described above, the BS can specify three antenna ports in the first SRS resource, and specify the same antenna ports as the first SRS resource or different antenna ports in the second SRS resource.

[0414] When the higher-layer parameter "usage" is configured as "antenna switching", the UE can use the mapping between the receiving antenna in the UE and the SRS antenna port indicated by the BS to perform SRS transmission.

[0415] As shown in Table 27, when SRS antenna ports 0, 1, and 2 are configured in the first SRS resource, the UE can map its transmit / receive antenna ports 0, 1, and 2 to transmit SRS signals. Furthermore, when SRS antenna ports 0, 1, and 2 are configured in the second SRS resource, the UE can map its transmit / receive antenna ports 3, 4, and 5 to antenna ports that are different from those used for transmitting SRS signals in the first SRS resource.

[0416] Alternatively, when SRS antenna ports 0, 1, and 2 are configured in the second SRS resource, the UE can take into account the switching operations of each of the four receive antenna sets due to the physical structure of internal components, and map transmit / receive antenna ports 4, 5, and 6 to UEs that are different from the antenna ports used to transmit SRS signals in the first SRS resource. As described above, the BS and UE can transmit SRS signals using an antenna consisting of three different transmit antenna sets out of the eight receive antennas, thus allowing UEs supporting 3T8R to determine a better antenna set later.

[0417] [Table 27]

[0418] In the above description, an embodiment in which the SRS antenna port numbers indicated for the first SRS resource and the second SRS resource are respectively indicated as {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2} has been described. However, the embodiment in which different antenna ports are explicitly indicated can be similarly applied and extended, such that the SRS antenna port numbers indicated for the first SRS resource are {SRS antenna port 0, SRS antenna port 1, SRS antenna port 2}, and the SRS antenna port numbers indicated for the second SRS resource are {SRS antenna port 3, SRS antenna port 4, SRS antenna port 5}.

[0419] The above-described operations of BS and UE for 3T6R and 3T8R can be extended as described in the first to fifth embodiments for 3T4R, and the configured SRS resources and antenna switching related configurations can be switched and applied at least partially.

[0420] The above embodiments of this disclosure (e.g., the first to sixth embodiments) can be combined and implemented.

[0421] Figure 11 This is a diagram illustrating the operation of the BS and UE according to an embodiment of the present disclosure.

[0422] It can be implemented based on the above embodiments of this disclosure (e.g., the first to the sixth embodiments). Figure 11 Operations of BS and UE in the system.

[0423] In operation 1100, the BS can receive UE capability information from the UE. At this time, the UE capabilities that can be reported may include UE capabilities associated with the uplink transmission functions of a UE supporting three transmit antennas and the SRS support method for antenna switching, as defined in the first to sixth embodiments. For example, the UE capability information may include information indicating the UE's antenna switching capabilities, and this information may indicate that the UE can transmit SRS through four or more receive antenna ports in three transmit antenna ports. For example, the UE capability information may also include information indicating the band pair for uplink transmission switching and information about the switching periodicity for uplink transmission switching. Operation 1100 can be omitted.

[0424] In operation 1105, the BS can send configuration information (e.g., configuration information for SRS) to the UE based on UE capability information reported by the UE via higher-layer signaling. For example, the BS may include SRS support methods defined in the first to sixth embodiments for SRS resource configuration and antenna switching for a UE with three transmit antennas to perform signaling, and may define and configure higher-layer signaling for combinations of one or more of these methods in the UE. The UE can identify parameters related to the configuration of SRS resources and SRS resource sets based on the configuration information. For example, the configuration information may include information indicating the number of SRS antenna ports.

[0425] In operation 1110, the BS can receive SRS from the UE. For example, the 3TX UE can determine one of the four antenna ports used for SRS that does not transmit SRS through, and transmit SRS to the BS based on the other three antenna ports besides that one antenna port. For example, the antenna port that does not transmit SRS can be determined based on the second embodiment described above. For example, the BS can receive SRS from the UE based on the antenna switching method configured in the UE as defined in the first to sixth embodiments that supports a UE with three transmit antennas.

[0426] The flowchart above illustrates an exemplary method that can be implemented according to the principles of this disclosure, and various modifications can be made to the method shown in the flowchart in this specification. For example, although shown as a series of steps, the individual steps in the figures may overlap, be generated in parallel, be generated in different orders, or be generated several times. In another example, these steps may be omitted or replaced with other steps.

[0427] The above embodiments of this disclosure (e.g., the first to sixth embodiments) can be derived from... Figure 12 terminals and Figure 13 BS execution.

[0428] Figure 12 This is a diagram illustrating the structure of a terminal in a wireless communication system according to an embodiment of the present disclosure.

[0429] refer to Figure 12 The terminal may include a transceiver comprising a terminal receiver 12-00 and a terminal transmitter 12-10, a memory (not shown), and a terminal processor 12-05 (or a terminal controller or processor). The transceiver 12-00 and 12-10, the memory, and the terminal processor 12-05 of the terminal may operate according to the communication method described above. However, the components of the terminal are not limited to the examples described above. For example, the terminal may include more or fewer elements than those described above. Furthermore, the transceiver, memory, and processor may be implemented as a single chip.

[0430] A transceiver can transmit signals to and receive signals from a BS. These signals can include control information and data. For this purpose, the transceiver can include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal and an RF receiver for low-noise amplification of the received signal and down-converting the frequency. However, this is only one embodiment of the transceiver, and the components of the transceiver are not limited to RF transmitters and RF receivers.

[0431] In addition, the transceiver can receive signals via a radio channel, output signals to the processor, and transmit signals output from the processor via a radio channel.

[0432] The memory can store the programs and data required for the operation of the terminal. In addition, the memory can store control information or data included in signals sent and received by the terminal. The memory can be configured using storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. There can be multiple memories.

[0433] Furthermore, the processor can control a series of processes that enable the terminal to operate according to the above embodiments. For example, the processor can identify that the purpose of the SRS resource set is configured for antenna switching and control the terminal's components to transmit SRS based on x antennas out of the terminal's y receive antennas. There can be multiple processors, and each processor can execute programs stored in memory to control the operation of the terminal's components.

[0434] Figure 13 This is a diagram illustrating the structure of a BS in a wireless communication system according to an embodiment of the present disclosure.

[0435] refer to Figure 13 The BS may include a transceiver comprising a BS receiver 13-00 and a BS transmitter 13-10, a memory (not shown), and a BS processor 13-05 (or a BS controller or processor). The transceivers 13-00 and 13-10, the memory, and the BS processor 13-05 of the BS may operate according to the communication method described above for the BS. However, the components of the BS are not limited to the examples described above. For example, the BS may include more or fewer components than those described above. Furthermore, the transceiver, memory, and processor may be implemented as a single chip.

[0436] A transceiver can send signals to a terminal and receive signals from a terminal. These signals can include control information and data. For this purpose, a transceiver can include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal and an RF receiver for low-noise amplification of the received signal and down-converting the frequency. However, this is only an example of a transceiver, and the components of a transceiver are not limited to RF transmitters and RF receivers.

[0437] In addition, the transceiver can receive signals via a radio channel, output signals to the processor, and transmit signals output from the processor via a radio channel.

[0438] The memory can store the programs and data required for the operation of the BS. The memory can store control information or data included in signals sent and received by the BS. The memory can be configured using storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media. There can be multiple memories.

[0439] The processor can control a series of processes that enable the BS to operate according to the embodiments described above. For example, the processor can control each component of the BS to send configuration information to the terminal, including the configuration of SRS resources and / or the configuration of SRS resource sets. Furthermore, the processor can configure the use of the SRS resource sets for antenna switching and control the components of the BS to receive SRS transmitted by x antennas out of y receiving antennas of the terminal. There can be multiple processors, and each processor can execute programs stored in memory to control the operations of the components of the BS.

[0440] The methods described in the claims or specification of this disclosure can be implemented in hardware, software, or a combination of hardware and software.

[0441] When the method is 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 may be configured to be executed by one or more processors within an electronic device. At least one program may include instructions to cause the electronic device to perform a method according to various embodiments of the present disclosure as defined by the appended claims and / or disclosed herein.

[0442] The program (software module or software) can be stored in non-volatile memory, including random access memory and flash memory, read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), disk storage devices, optical disc ROM (CD-ROM), digital versatile optical disc (DVD), or other types of optical storage devices or magnetic tape cartridges. Alternatively, any combination of some or all of these can form the memory storing the program. Furthermore, an electronic device may include multiple such memories.

[0443] Additionally, the program can be stored in an attachable storage device that can access the electronic device via a communication network such as the Internet, intranet, local area network (LAN), wide area network (WLAN), and storage area network (SAN), or a combination thereof. Such a storage device can access the electronic device via an external port. Furthermore, a separate storage device on the communication network can access the device executing embodiments of this disclosure.

[0444] In the detailed embodiments described above, the elements included in this disclosure are expressed in a singular or plural form according to the presented embodiments. However, for ease of description, the singular or plural form is suitably chosen for the presented situation, and this disclosure is not limited to elements expressed in a singular or plural form. Thus, an element expressed in a plural form may also include a single element, or an element expressed in a singular form may include multiple elements.

[0445] Embodiments of this disclosure, described and illustrated in the specification and accompanying drawings, have been presented to readily explain the technical content of this disclosure and to aid in understanding it, and are not intended to limit the scope of this disclosure. That is, it will be apparent to those skilled in the art that other modifications and changes can be made based on the technical concepts of this disclosure. Furthermore, the corresponding embodiments described above can be combined as needed. For example, one embodiment of this disclosure can be partially combined with other embodiments to operate a base station and a terminal. As an example, embodiments 1 and 2 of this disclosure can be combined with each other to operate a base station and a terminal. Additionally, the embodiments of this disclosure are applicable to other communication systems, and other variations based on the technical scope of the embodiments can also be implemented.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: Receive configuration information for a sounding reference signal (SRS) from a base station (BS), the configuration information including first information indicating the number of antenna ports of the SRS; When the first information indicates 3 as the number of antenna ports, determine one of the four antenna ports used for the SRS that will not transmit the SRS through it; as well as The SRS is transmitted to the BS via three antenna ports in addition to the one antenna port.

2. The method according to claim 1, wherein, The antenna port that does not transmit the SRS is either the antenna port corresponding to the lowest antenna port number or the antenna port corresponding to the highest antenna port number among the four antenna ports.

3. The method according to claim 1, further comprising: The BS receives a second message indicating that it will not transmit the SRS through the one antenna port. Specifically, based on the second information, it is determined which antenna port will not transmit the SRS through it.

4. The method according to claim 1, wherein, The antenna port that does not transmit the SRS is determined based on the comb offset value. Wherein, when the comb offset value is even, the antenna port that does not transmit the SRS through it is determined as the antenna port among the four antenna ports corresponding to the highest antenna port number; and Wherein, when the comb offset value is odd, the antenna port that does not transmit the SRS through it is determined to be the antenna port among the four antenna ports that corresponds to the lowest antenna port number.

5. The method according to claim 1, wherein, The antenna port that does not transmit the SRS is determined based on the comb offset value and the cyclic shift value.

6. The method according to claim 1, further comprising: The terminal capability information is sent to the BS, and the terminal capability information includes third information indicating the antenna switching capability of the terminal. The third piece of information indicates that the terminal can transmit the SRS through four or more receive antenna ports on three transmit antenna ports. The configuration information also includes information about the SRS resource set used for antenna switching, and The SRS resource set includes multiple SRS resources, and each of the multiple SRS resources corresponds to four SRS ports.

7. The method according to claim 6, further comprising: Receive mode information from the BS, the mode information indicating one of the four SRS ports of each SRS resource that does not transmit the SRS through it; Based on the mode information, determine the three SRS ports among the four SRS ports that correspond to the three transmit antenna ports; as well as The SRS is sent to the BS based on the multiple SRS resources and the three SRS ports.

8. The method according to claim 6, wherein, The terminal capability information also includes fourth information indicating the frequency band pair used for uplink transmission handover and fifth information regarding the handover periodicity of the uplink transmission handover. The fourth piece of information indicates that the terminal supports switching from three transmit antenna ports to two transmit antenna ports, and The switching periodicity is 280µs.

9. A method performed by a base station (BS) in a wireless communication system, the method comprising: The terminal is sent configuration information for a sounding reference signal (SRS), the configuration information including first information indicating the number of antenna ports of the SRS; as well as Receive the SRS from the terminal. Wherein, when the first information indicates 3 as the number of antenna ports, the SRS is received based on three of the four antenna ports used for the SRS, excluding the one antenna port through which the SRS will not be transmitted.

10. The method of claim 9, further comprising: Send a second message to the terminal indicating that the SRS is not transmitted through the one antenna port through which it is transmitted. Specifically, based on the second information, it is determined that the SRS is not transmitted through the antenna port through which it is transmitted.

11. The method according to claim 9, wherein, The SRS not being transmitted through the one antenna port is determined based on the comb offset value. Wherein, when the comb offset value is even, the antenna port through which the SRS is not transmitted is determined to be the antenna port corresponding to the highest antenna port number among the four antenna ports; and Wherein, when the comb offset value is odd, the antenna port through which the SRS is not transmitted is determined to be the antenna port among the four antenna ports corresponding to the lowest antenna port number.

12. The method according to claim 9, further comprising: The terminal receives terminal capability information, including third information indicating the terminal's antenna switching capabilities. The third piece of information indicates that the terminal can transmit the SRS through four or more receive antenna ports on three transmit antenna ports. The configuration information also includes information about the SRS resource set used for antenna switching, and The SRS resource set includes multiple SRS resources, and each of the multiple SRS resources corresponds to four SRS ports.

13. The method of claim 12, further comprising: Send mode information to the terminal, the mode information indicating that the SRS of each SRS resource is not transmitted through one of its four SRS ports, and the three SRS ports corresponding to the three transmit antenna ports are identified based on the mode information; and The SRS is received from the terminal based on the multiple SRS resources and the three SRS ports.

14. A terminal in a wireless communication system, the terminal comprising: transceiver; and A controller, functionally connected to the transceiver, The controller is configured as follows: Receive configuration information for a sounding reference signal (SRS) from a base station (BS), the configuration information including first information indicating the number of antenna ports of the SRS; When the first information indicates 3 as the number of antenna ports, determine one of the four antenna ports used for the SRS that will not transmit the SRS through it; as well as The SRS is transmitted to the BS via three antenna ports in addition to the one antenna port.

15. The terminal according to claim 14, wherein, The antenna port that does not transmit the SRS is either the antenna port corresponding to the lowest antenna port number or the antenna port corresponding to the highest antenna port number among the four antenna ports.

Images