Method and apparatus for measuring UE-to-UE cross-link interference in wireless communication system

Abstract

The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates beyond 4G communication systems such as Long Term Evolution (LTE). Specifically, a method for operating a UE in a wireless communication system according to various embodiments of the present disclosure may comprise: a step of receiving, from a base station, information indicating that a CLI measurement is triggered by identifying the UE as an interfered UE, a step of receiving, after the CLI measurement is triggered, one or more cell-level reference signals from one or more UEs in a second cell adjacent to the first cell in which the UE is located, and a step of transmitting, to the base station, a cell-level measurement report including a result of measuring the RSRP of the received one or more cell-level RSs.

Description

Technical Field

[0001] The present disclosure relates generally to a wireless communication system, and more particularly, to a method and apparatus for measuring UE-to-UE cross-link interference in a wireless communication system. Background Art

[0002] Recently, in order to improve communication quality, there is an increasing demand for a scheme for effectively measuring UE-to-UE cross-link interference.

[0003] The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with respect to the present disclosure.

[0004] Considering the development of wireless communication from generation to generation, technologies have been developed mainly for services targeting humans, such as voice calls, multimedia services, and data services. Following the commercialization of 5G (5th generation) communication systems, the number of connected devices is expected to grow exponentially. These will be increasingly connected to communication networks. Examples of connected things may include vehicles, robots, drones, home appliances, displays, smart sensors connected to various infrastructures, construction machinery, and factory equipment. Mobile devices are expected to develop in various form factors, such as augmented reality glasses, virtual reality headsets, and hologram devices. In order to provide various services by connecting hundreds of billions of devices and things in the 6G (6th generation) era, efforts have been continuously made to develop improved 6G communication systems. For these reasons, 6G communication systems are called super 5G systems.

[0005] The 6G communication system, which is expected to be commercialized around 2030, will have a peak data rate of terabit (1,000 gigabit) per second (bps) and a radio latency of less than 100 μsec, and will therefore be 50 times faster and have 1 / 10 the radio latency of the 5G communication system.

[0006] To achieve such high data rates and ultra-low latency, 6G communication systems have been considered to be implemented in the terahertz (THz) band (e.g., 95 gigahertz (GHz) to 3THz band). It is expected that since the path loss and atmospheric absorption in the THz band are more serious than those in the mmWave band introduced in 5G, technologies capable of ensuring the signal transmission distance (i.e., coverage) will become more critical. As the main technologies for ensuring coverage, it is necessary to develop radio frequency (RF) elements, antennas, novel waveforms with better coverage than orthogonal frequency division multiplexing (OFDM), beamforming and massive multiple input multiple output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, and multi-antenna transmission technologies such as massive antennas. In addition, new technologies for improving THz band signal coverage, such as metamaterial-based lenses and antennas, orbital angular momentum (OAM), and reconfigurable smart surfaces (RIS), have been discussed.

[0007] In addition, in order to improve spectrum efficiency and overall network performance, the following technologies have been developed for 6G communication systems: full-duplex technology for enabling uplink transmission and downlink transmission to use the same frequency resources at the same time; network technology for utilizing satellites, high altitude platform stations (HAPS), etc. in an integrated manner; improved network structure for supporting mobile base stations, etc. and realizing network operation optimization and automation, etc.; dynamic spectrum sharing technology via conflict avoidance based on spectrum usage prediction; use of artificial intelligence (AI) in wireless communication for improving the overall network operation by utilizing AI from the design stage of developing 6G and internalizing end-to-end AI support functions; and next-generation distributed computing technology for overcoming the limitations of UE computing capabilities through accessible ultra-high performance communication and computing resources on the network, such as mobile edge computing (MEC), cloud, etc. In addition, attempts to strengthen connectivity between devices, optimize networks, promote softwareization of network entities, and increase openness of wireless communications are continuing by designing new protocols to be used in 6G communication systems, developing mechanisms for realizing hardware-based security environments and secure use of data, and developing technologies for maintaining privacy.

[0008] Research and development of 6G communication systems in hyperconnectivity, including person-to-machine (P2M) and machine-to-machine (M2M), are expected to allow the next hyperconnectivity experience. Specifically, it is expected that services such as truly immersive extended reality (XR), high-fidelity mobile holograms, and digital replicas can be provided through 6G communication systems. In addition, services such as remote surgery, industrial automation, and emergency response for enhanced safety and reliability will be provided through 6G communication systems, so that these technologies can be applied to various fields such as industry, medical care, automobiles, and home appliances. Summary of the invention

[0009] Solution to the problem

[0010] The present disclosure relates to a wireless communication network, and more particularly, to a terminal in a wireless communication system and a communication method thereof.

[0011] According to one aspect of the present disclosure, a method for operating a UE in a wireless communication system may include: receiving information indicating that a cross-link interference (CLI) measurement is triggered from a base station by identifying the UE as an interfered UE; after the CLI measurement is triggered, receiving one or more cell-level reference signals (RS) from one or more UEs in a second cell adjacent to a first cell where the UE is located; and sending a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of the received one or more cell-level RSs to the base station, wherein the one or more cell-level RSs are received in the same sequence on the same radio resources.

[0012] Advantageous Effects of the Invention

[0013] Aspects of the present disclosure are to address at least the above problems and / or disadvantages and to provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide an efficient communication method in a wireless communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0015] Figure 1 A wireless communication system according to various embodiments of the present disclosure is shown;

[0016] Figure 2 The configuration of a base station in a wireless communication system according to various embodiments of the present disclosure is shown;

[0017] Figure 3 The configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure is shown;

[0018] Figure 4 One type of cross-link interference (CLI) related to various embodiments of the present disclosure is shown;

[0019] Figure 5 One type of UE-to-UE CLI related to various embodiments of the present disclosure is shown;

[0020] Figure 6 shows the CLI measurement steps according to various embodiments of the present disclosure;

[0021] Figure 7 A cell-level CLI measurement method according to various embodiments of the present disclosure is shown;

[0022] Figure 8 shows the order of cell-level CLI measurements according to various embodiments of the present disclosure;

[0023] Fig. 9 A cell-level sounding reference signal (SRS) transmission method according to various embodiments of the present disclosure is shown;

[0024] Fig.10 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown;

[0025] Fig.11 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown;

[0026] Fig.12 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown;

[0027] Fig.13 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown;

[0028] Fig.14A A method for solving signal distortion according to various embodiments of the present disclosure is shown;

[0029] Fig. 14B A method for solving signal distortion according to various embodiments of the present disclosure is shown;

[0030] Fig.15 A UE-level CLI measurement method according to various embodiments of the present disclosure is shown;

[0031] Fig.16 A method for configuring SRS resources at the UE level between cells according to various embodiments of the present disclosure is shown;

[0032] Fig.17 A method for configuring UE-level SRS resources within a cell according to various embodiments of the present disclosure is shown;

[0033] Fig.18 A UE-to-UE CLI mitigation method according to various embodiments of the present disclosure is shown;

[0034] Fig.19 A UE-to-UE CLI mitigation method according to various embodiments of the present disclosure is shown;

[0035] Fig. 20 A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0036] Fig.21A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0037] Fig. 22 A table showing mapping between cell IDs and SRS resources according to various embodiments of the present disclosure;

[0038] Fig.23 A method for measuring RSRP with respect to a cell-level SRS according to various embodiments of the present disclosure is shown;

[0039] Fig.24 A method for measuring RSRP with respect to a cell-level SRS according to various embodiments of the present disclosure is shown;

[0040] Fig.25 shows how RSRP measurement errors (underestimation) occur according to various embodiments of the present disclosure;

[0041] Fig.26 A method for resolving RSRP measurement errors according to various embodiments of the present disclosure is shown;

[0042] Fig. 27 A method for resolving RSRP measurement errors according to various embodiments of the present disclosure is shown;

[0043] Fig.28 A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0044] Fig.29 A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0045] Fig.30 A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0046] Fig.31 A method for transmitting a cell-level SRS in view of a location of a terminal according to various embodiments of the present disclosure is shown;

[0047] Fig.32 A mapping table of SRS resources for intra-cell and inter-cell CLI measurements according to various embodiments of the present disclosure is shown;

[0048] Fig.33 An intra-cell CLI measurement method according to various embodiments of the present disclosure is shown;

[0049] Fig.34 An intra-cell CLI measurement method according to various embodiments of the present disclosure is shown;

[0050] Fig.35 A method for solving ADC saturation according to various embodiments of the present disclosure is shown;

[0051] Fig.36 A method for solving ADC saturation according to various embodiments of the present disclosure is shown; and

[0052] Fig.37 An interfering cell detection method according to various embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0053] Aspects of the present disclosure are to address at least the above-mentioned problems and / or disadvantages and to provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide a terminal in a wireless communication system and a communication method thereof.

[0054] According to various embodiments disclosed herein, a method for operating a UE in a wireless communication system may include: receiving information from a base station indicating that a cross-link interference (CLI) measurement is triggered by identifying the UE as an interfered UE; after the CLI measurement is triggered, receiving one or more cell-level reference signals (RS) from one or more UEs in a second cell adjacent to a first cell where the UE is located; and sending a cell-level measurement report to the base station including a result of measuring a reference signal received power (RSRP) of the received one or more cell-level RSs, wherein the one or more cell-level RSs are received in the same sequence on the same radio resources.

[0055] According to various embodiments disclosed herein, a method for operating a base station in a wireless communication system may include: identifying a UE as an interfered UE when channel quality information included in a channel state information (CSI) report received from the UE is less than a first threshold; sending information indicating that a CLI measurement is triggered to the interfered UE; after the CLI measurement is triggered, receiving a cell-level measurement report from the UE including results of measuring a reference signal received power (RSRP) of multiple cell-level reference signals (RS) of multiple cells adjacent to a first cell where the UE is located; and identifying a cell corresponding to an RSRP equal to / higher than a second threshold as an interfering cell based on the cell-level measurement report, wherein the multiple cell-level RSs are sent in the same sequence on the same radio resources, and the first threshold and the second threshold are different from each other.

[0056] According to various embodiments disclosed herein, a UE device in a wireless communication system may include a transceiver, a memory, and a controller, wherein the controller is configured to: receive information indicating that a cross-link interference (CLI) measurement is triggered from a base station by identifying a UE as an interfered UE; after the CLI measurement is triggered, receive one or more cell-level reference signals (RS) from one or more UEs in a second cell adjacent to a first cell where the UE is located; and send a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of the received one or more cell-level RSs to the base station, wherein the one or more cell-level RSs are received in the same sequence on the same radio resources.

[0057] According to various embodiments disclosed herein, a base station device in a wireless communication system may include a transceiver, a memory, and a controller, wherein the controller is configured to: identify the UE as an interfered UE when channel quality information included in a channel state information (CSI) report received from the UE is less than a first threshold; send information indicating that CLI measurement is triggered to the interfered UE; after the CLI measurement is triggered, receive a cell-level measurement report from the UE including results of measuring reference signal received power (RSRP) of multiple cell-level reference signals (RS) of multiple cells adjacent to a first cell where the UE is located; and identify a cell corresponding to an RSRP equal to / higher than a second threshold as an interfering cell based on the cell-level measurement report, wherein the multiple cell-level RSs are sent in the same sequence on the same radio resources, and the first threshold and the second threshold are different from each other.

[0058] Before proceeding to the following detailed description, it may be helpful to set forth definitions of certain words and phrases used throughout this patent document: the terms "include" and "comprising" and their derivatives mean including but not limited to; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean including, included within, interconnected with, containing, contained within, connected to or connected with, coupled to or coupled with, communicable with, cooperating with, interleaved, juxtaposed, proximate to, bound to or bound with, having, having the property of, etc.; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two thereof. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely.

[0059] In addition, the various functions described below may be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data, or a portion thereof, suitable for implementation in a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disk (DVD), or any other type of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical, or other communication links that transmit temporary electrical or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and later rewritten, such as rewritable optical disks or erasable memory devices.

[0060] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.

[0061] Mode for the Invention

[0062] Discussed below Figures 1 to 37 The various embodiments used to describe the principles of the present disclosure in this patent document are illustrative only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0063] Hereinafter, the present disclosure relates to a method and apparatus for measuring UE-to-UE cross link interference (CLI) in a wireless communication system. Specifically, in the present disclosure, an operation method for enabling a terminal to effectively measure UE-to-UE CLI in a wireless communication system may be described. In order to enable the terminal to effectively measure UE-to-UE CLI, CLI measurement may be divided into two steps (inter-cell CLI measurement step and intra-cell CLI measurement step) and described.

[0064] Figure 1 A wireless communication system according to various embodiments of the present disclosure is shown. Figure 1 An example of a base station 110, a terminal 120, and a terminal 130 as a part of a node using a radio channel in a wireless communication system is shown. Figure 1Only one base station is shown, but base stations identical to or similar to base station 110 may also be included.

[0065] The base station 110 is a network infrastructure configured to provide wireless connections to the terminals 120 and 130. The base station 110 has a coverage area defined as a predetermined geographical area based on the distance at which a signal can be transmitted. In addition to "base station", the base station 110 may also be referred to as an "access point (AP)", "eNodeB (eNB)", "fifth generation node (5G node)", "next generation node B (gNB)", "radio point", "transmission / reception point (TRP)" or other terms with equivalent technical meanings.

[0066] Each of the terminal 120 and the terminal 130 refers to a device used by a user to perform communication with the base station 110 through a radio channel. In some cases, at least one of the terminal 120 and the terminal 130 may be operated without user intervention. That is, at least one of the terminal 120 and the terminal 130 may be a device configured to perform machine type communication (MTC) without being carried by a user. In addition to the “terminal”, each of the terminal 120 and the terminal 130 may also be referred to as a “user equipment (UE)”, “mobile station”, “subscriber station”, “remote terminal”, “wireless terminal”, “user device” or other terms with equivalent technical meanings.

[0067] The base station 110, the terminal 120, and the terminal 130 may transmit and receive radio signals in the mmWave frequency band (e.g., 28 GHz, 30 GHz, 38 GHz, and 60 GHz). The base station 110, the terminal 120, and the terminal 130 may perform beamforming to improve channel gain. As used herein, beamforming may include transmit beamforming and receive beamforming. That is, the base station 110, the terminal 120, and the terminal 130 may assign directivity to the transmitted or received signal. To this end, the base station 110 and the terminals 120 and 130 may select service beams 112, 113, 121, and 131 through a beam search or beam management process. After selecting the service beams 112, 113, 121, and 131, subsequent communications may be performed through resources having a quasi-co-location (QCL) relationship with the resources used to transmit the service beams 112, 113, 121, and 131.

[0068] The first antenna port and the second antenna port may be evaluated as having a QCL relationship if a large-scale characteristic of a channel used to communicate symbols on a first antenna port can be inferred from a channel used to communicate symbols on a second antenna port. For example, the large-scale characteristic may include at least one of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial receiver parameters.

[0069] Figure 2 The configuration of a base station in a wireless communication system according to various embodiments of the present disclosure is shown. Figure 2 The exemplary configuration illustrated in FIG. 1 may be understood as the configuration of the base station 110. As used herein, terms such as “part” and “-device” refer to a unit configured to process at least one function or operation and may be implemented as hardware, software, or a combination of hardware and software.

[0070] refer to Figure 2 , the base station includes a wireless communication part 210 , a backhaul communication part 220 , a storage part 230 and a controller (or processor) 240 .

[0071] The wireless communication section 210 performs a function for transmitting / receiving a signal through a radio channel. For example, the wireless communication section 210 performs a function for converting between a baseband signal and a bit string according to the physical layer specification of the system. For example, during data transmission, the wireless communication section 210 encodes and modulates the transmitted bit string, thereby generating a complex symbol. In addition, during data reception, the wireless communication section 210 demodulates and decodes the baseband signal, thereby recovering the received bit string.

[0072] In addition, the wireless communication section 210 up-converts the baseband signal into a radio frequency (RF) band signal, transmits the RF band signal through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. To this end, the wireless communication section 210 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital-to-analog (DAC) converter, an analog-to-digital (ADC) converter, etc. In addition, the wireless communication section 210 may include multiple transmission / reception paths. In addition, the wireless communication section 210 may include at least one antenna array, and the at least one antenna array includes a plurality of antenna elements.

[0073] In terms of hardware, the wireless communication part 210 may include a digital unit and an analog unit. The analog unit may include a plurality of sub-units according to operating power, operating frequency, etc. The digital unit may be implemented as at least one processor (eg, a digital signal processor (DSP)).

[0074] The wireless communication section 210 transmits and receives signals as described above. Therefore, all or part of the wireless communication section 210 may be referred to as a "transmitter," "receiver," or "transceiver." In addition, as will be described below, transmission and reception performed through a radio channel will be used in the sense of including the above-mentioned processing performed by the wireless communication section 210.

[0075] The backhaul communication section 220 provides an interface for performing communication with other nodes within the network. That is, the backhaul communication section 220 converts a bit string sent from the base station to other nodes (e.g., other access nodes, other base stations, upper nodes, core networks, etc.), and converts a physical signal received from other nodes into a bit string.

[0076] The storage part 230 stores data such as default programs, applications, configuration information, etc. for the operation of the base station. The storage part 230 can be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. The storage part 230 also provides the stored data at the request of the controller 240.

[0077] The controller 240 controls the overall operation of the base station. For example, the controller 240 sends and receives signals through the wireless communication part 210 or the backhaul communication part 220. In addition, the controller 240 records data in the storage part 230 and reads data. The controller 240 can also perform the functions of the protocol stack required by the communication specification. According to another example of implementation, the protocol stack can be included in the wireless communication part 210. To this end, the controller 240 may include at least one processor.

[0078] According to various embodiments, the controller 240 may control the base station so as to perform operations according to various embodiments described later.

[0079] Figure 3 A configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure is shown. Figure 3 The exemplary configuration shown in FIG. 1 may be understood as a configuration of the terminal 120. As used herein, terms such as "part" and "-device" refer to a unit configured to process at least one function or operation and may be implemented as hardware, software, or a combination of hardware and software.

[0080] refer to Figure 3 , the terminal includes a communication part 310 , a storage part 320 and a controller (or processor) 330 .

[0081] The communication part 310 performs a function for sending / receiving a signal through a radio channel. For example, the communication part 310 performs a function for converting between a baseband signal and a bit string according to the physical layer specification of the system. For example, during data transmission, the communication part 310 encodes and modulates the transmitted bit string to generate a complex symbol. In addition, during data reception, the communication part 310 demodulates and decodes the baseband signal to restore the received bit string. In addition, the communication part 310 up-converts the baseband signal to an RF band signal, transmits the RF band signal through an antenna, and down-converts the RF band signal received by the antenna to a baseband signal. For example, the communication part 310 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc.

[0082] In addition, the communication section 310 may include multiple transmit / receive paths. In addition, the communication section 310 may include at least one antenna array including multiple antenna elements. In terms of hardware, the communication section 310 may include digital circuits and analog circuits (e.g., radio frequency integrated circuits (RFICs)). The digital circuits and analog circuits may be implemented as a single package. In addition, the communication section 310 may include multiple RF chains. In addition, the communication section 310 may perform beamforming.

[0083] The communication section 310 transmits and receives signals as described above. Therefore, all or part of the communication section 310 may be referred to as a "transmitter," "receiver," or "transceiver." In addition, as will be described below, transmission and reception performed through a radio channel will be used in the sense of including the above-mentioned processing performed by the communication section 310.

[0084] The storage part 320 stores data such as default programs, applications, configuration information, etc. for the operation of the terminal. The storage part 320 can be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. The storage part 320 also provides the stored data at the request of the controller 330.

[0085] The controller 330 controls the overall operation of the terminal. For example, the controller 330 sends and receives signals through the communication part 310. In addition, the controller 330 records data in the storage part 320 and reads data. The controller 330 can also perform the functions of the protocol stack required by the communication specification. To this end, the controller 330 may include at least one processor or microprocessor, or may be a part of a processor. In addition, the communication part 310 and a part of the controller 330 may be referred to as a communication processor (CP).

[0086] According to various embodiments, the controller 330 may control the terminal so as to perform operations according to various embodiments described later.

[0087] As will be used in the following description, terms for identifying access nodes, terms representing network entities, terms representing messages, terms representing interfaces between network entities, terms representing various identification information, etc. are examples provided for convenience of description. Therefore, the present disclosure is not limited to the terms described later, and other terms representing objects with equivalent technical meanings may be used.

[0088] Figure 4 One type of cross-link interference (CLI) relevant to various embodiments of the present disclosure is shown.

[0089] refer to Figure 4 , which can describe the manner in which CLI occurs between terminals or between a terminal and a base station. For example, UL to DL interference may correspond to interference that occurs when the base station 110 transmits a downlink signal to the terminal 120 due to an uplink signal from a terminal 420 located in a cell adjacent to the cell in which the terminal 120 is located, and may be referred to as UE to UE interference. That is, interference that occurs in a time slot in which the terminal 120 is scheduled to receive a downlink signal due to an uplink signal from the terminal 420 in the adjacent cell may reduce the quality of the downlink signal received from the base station 110.

[0090] As another example, DL-to-UL interference may correspond to interference that occurs due to a downlink signal transmitted by a base station 110 in a cell adjacent to the cell in which the terminal 420 is located when the terminal 420 transmits an uplink signal to the base station 410, and may be referred to as gNB-to-gNB interference. That is, interference that occurs in a time slot through which the terminal 420 is scheduled to transmit an uplink signal due to a downlink signal from the base station 110 in the adjacent cell may reduce the quality of the uplink signal received from the terminal 110.

[0091] In the present disclosure, a detailed method in which, if the above-mentioned UE-to-UE interference occurs, the terminal 120 measures the interference caused by the terminal 420 in the adjacent cell may be described. Hereinafter, the terminal (or UE) may refer to the terminal 120 that receives the interference signal. In addition, in the present disclosure, the terminal that receives the interference signal may be referred to as a victim terminal, and the base station of the cell where the victim terminal is located may be referred to as an interfered base station. In addition, in the present disclosure, the terminal that sends the interference signal may be referred to as an aggressor terminal, and the base station of the cell where the interference terminal is located may be referred to as an interfering base station.

[0092] Figure 5 One type of UE-to-UE CLI related to various embodiments of the present disclosure is shown.

[0093] refer to Figure 5 , the number of times a terminal measures UE-to-UE CLI in a dynamic time division duplex (D-TDD) system and a full-duplex (FD) system can be compared. In a D-TDD system, UE-to-UE CLI can occur in cells with different downlink and uplink configurations. For example, if downlink transmission is scheduled for a terminal in a cell where an interfered base station and an interfered terminal are located, some of the potential interfering terminals in two cells for which uplink transmission is scheduled in an adjacent cell may cause interference in the interfered terminal. Therefore, assuming that N terminals are located in each cell, the interfered terminal may require up to 2N CLI measurements to verify (or detect, identify, select) the interfering terminal that sends the interfering signal.

[0094] In contrast, UE-to-UE CLI can occur with the help of all neighboring cells in the FD system. For example, if six cells are adjacent to the cell where the interfered terminal is located, all terminals located in all adjacent cells may be potential interfering terminals. Therefore, assuming that N terminals are located in each cell, the interfered terminal may need up to 6N CLI measurements to verify (or detect, identify, select) the interfering terminal located in the adjacent cell. In addition, unlike the D-TDD system, other terminals located in the cell where the interfered terminal is located may be potential interfering terminals, and the interfered terminal may therefore need to measure CLI about other terminals in the cell. Therefore, in the FD system, the interfered terminal may need to perform up to (7N-1) CLI measurements.

[0095] Since the number of CLI measurements is too many compared to the D-TDD system, resources for measuring UE-to-UE CLI may be wasted in the FD system. Therefore, a method for enabling an interfered terminal to efficiently measure UE-to-UE CLI in the FD system may be described in the present disclosure.

[0096] Figure 6 The CLI measurement steps according to various embodiments of the present disclosure are shown.

[0097] refer to Figure 6 , for effective UE-to-UE CLI measurement, the terminal may perform two separate steps of CLI measurement (e.g., a first step and a second step). The first step may refer to an inter-cell CLI measurement operation, and the second step may refer to an intra-cell CLI measurement operation. In addition, the second step described in the present disclosure may be optionally performed by the interfered terminal according to the communication environment (e.g., if no neighboring cell is verified as an interfering cell in the first step, or if no uplink / downlink transmission resources are allocated to the neighboring cell verified as an interfering cell).

[0098] Specifically, the first step may refer to a step of determining an interfering cell including an interfering base station as an interfering cell through cell unit CLI measurement (i.e., cell-level CLI measurement). Therefore, in the first step, the cell-level CLI measurement may be performed as many times as the number of neighboring cells other than the cells to which the interfered base station and the interfered terminal belong. The second step may refer to a step of specifying the interfering terminal by measuring the CLI of a terminal within the cell or a terminal in the interfering cell (i.e., UE-level CLI measurement). In the second step, when measuring CLI about the terminal within the cell, UE-level CLI measurement may be performed about the terminal within the cell excluding the interfered cell. Therefore, the number of times CLI is measured in the second step may be N-1 or 2N-1 (for example, if there is no inter-cell CLI, and if there is only intra-cell CLI). Therefore, the advantage of the two-step inter-cell CLI measurement according to the present disclosure is that the number of measurements is reduced compared to the method of measuring CLI about all terminals in neighboring cells. (For example, if N=10, then it is 78%, if N= , then 85%) or (For example, if N=10, then it is 64%, if N= , it is 73%).

[0099] Figure 7 A cell-level CLI measurement method according to various embodiments of the present disclosure is illustrated.

[0100] refer to Figure 7 , an operation flow between a base station and a terminal located in a first cell (e.g., a cell where a potentially interfered base station and a potentially interfered terminal are located) and a neighboring cell (e.g., a cell where a potentially interfering base station and a potentially interfering terminal are located). A base station located in the first cell (e.g., a potentially interfered base station) may share a cell-level sounding reference signal (SRS) resource configuration with a base station in a neighboring cell (e.g., a potentially interfering base station), and the cell-level SRS resource may be predetermined through a coordination process with the base stations of the neighboring cells. The SRS used to detect the channel state is only an example of a reference signal (RS), and another RS ​​may be used. For example, a CLI measurement RS may be used. The CLI measurement RS may be an RS designed for UE-to-UE CLI measurement. The CLI measurement RS may be a signal for notifying a terminal that sends an RS that the RS will be sent at a specific location on a resource grid based on a resource configuration of a base station. In addition, the CLI measurement RS may be a signal for notifying a terminal that sends an RS that a sequence for sending the RS is sent based on a resource configuration of a base station.

[0101] Will refer to it later Fig. 9 The cell-level SRS resource configuration shared between base stations is described in detail.

[0102] In step (1-1), each potentially interfering base station may trigger cell-level SRS transmission from a potentially interfering terminal located in the corresponding cell based on the cell-level SRS resource configuration information shared with the base station of the first cell. If the cell-level SRS transmission is triggered by a potentially interfering base station, the potentially interfering terminal may send a cell-level SRS to the interfered terminal. In this case, the potentially interfering terminals located in each adjacent cell may send the cell-level SRS by sending the same sequence with respect to the same time and frequency resources of each cell. However, the potentially interfering terminals located in different cells may send the same sequence through different resources, or may send different sequences through the same resources.

[0103] In step (1-2), the terminal located in the first cell may send a channel state information (CIS) report to the base station of the first cell. The CSI report sent by the terminal may include feedback information about the CSI-RS sent from the base station of the first cell to the terminal (e.g., precoding matrix indicator (PMI), channel quality information (CQI), rank indicator RI, CSI-RS resource indicator (CRI), received signal strength indicator (RSSI) and / or layer indicator (LI)). The base station of the first cell may select (or pick) the terminal as an interfered terminal based on the feedback information included in the CSI report received from the terminal. For example, if the CQI value included in the CSI report is equal to / less than a specific threshold, the base station of the first cell may consider that interference occurs in the terminal, and may determine that the terminal in which the interference occurs is an interfered terminal. As another example, if the RSSI is equal to / less than a specific threshold, the base station of the first cell may consider that interference occurs in the terminal, and may determine that the terminal in which the interference occurs is an interfered terminal. In addition, if the CQI values ​​of the RSSI of multiple terminals are equal to / less than a specific threshold, the base station of the first cell determines that the corresponding terminal is an interfered terminal. Therefore, the interfered terminal can refer to one of the multiple terminals considered to be interfered terminals, and the number of interfered terminals is not necessarily limited to one.

[0104] If the terminal of the first cell is determined to be an interfered terminal, the base station of the first cell may be determined to be an interfered base station. The specific threshold may be a predetermined value and may be configured differently according to the communication environment (e.g., line of sight (LOS) or non-LOS (NLOS) environment). The interfered base station may send information about the measurement object to the terminal selected (or determined) as the interfered terminal through upper layer signaling (e.g., resource radio control (RRC) message). The information about the measurement object may include different information about each neighboring cell, and may include cell-level SRS resources to be sent by the potential interfering terminal located in each neighboring cell. In addition, by sending information about the measurement object, the interfered base station may trigger the interfered terminal to measure the reference signal received power (RSRP) of the cell-level SRS. For example, the interfered base station may send information about the measurement object to the interfered terminal, thereby instructing the interfered terminal to measure the RSRP of the cell-level SRS received from the potential interfering terminal located in each neighboring cell. The interfered terminal may measure the RSRP of the cell-level SRS received from the potential interfering terminal located in each neighboring cell. Since the cell-level SRS transmitted in each neighboring cell has different transmission resources and different sequences, the interfered terminal can measure the cell-level RSRP with respect to each cell.

[0105] In step (1-3), the interfered terminal may send a cell-level RSRP report obtained from the cell-specific measurement to the interfered base station. The cell-level RSRP report may include RSRP measurement values ​​for the cell-level SRS of each neighboring cell, which is used by the interfered base station to determine the interfering cell in the neighboring cell. In an embodiment, the interfered terminal may report a pair of RSRP measurement values ​​and resource IDs (e.g., IDs of resources for sending cell-level SRS for each cell) about the cell-level SRS to the interfered base station. In an embodiment, the interfered terminal may sort the resource IDs in descending order of the RSRP measurement values ​​about the cell-level SRS, and may report the resource IDs to the interfered base station. In an embodiment, the interfered terminal may select N (e.g., N is an integer equal to / greater than 1) resource IDs in descending order of the RSRP measurement values ​​about the cell-level SRS, and may report N pairs of resource IDs and RSRP measurement values ​​about the cell-level SRS to the interfered base station. In an embodiment, the interfered terminal may report a pair of resource ID and RSRP measurement value about the cell-level SRS to the interfered base station, and the RSRP measurement value about the cell-level SRS is equal to / greater than a specific threshold. In an embodiment, the interfered terminal may report a resource ID corresponding to the RSRP measurement value about the cell-level SRS to the interfered base station, and the RSRP measurement value about the cell-level SRS is equal to / greater than a specific threshold.

[0106] The cell-level RSRP report may also include an index used by the interfered base station to determine the interfering cell (e.g., an RSRP measurement value or threshold value for the maximum cell-level SRS). For example, upon receiving the cell-level RSRP report, the interfered base station may identify (or verify) that the corresponding neighboring cell is an interfering cell when the RSRP measurement value for the cell-level SRS is equal to / greater than a specific threshold. Alternatively, upon receiving the cell-level RSRP report, the interfered base station may (or verify) that the cell with the maximum RSRP measurement value for the cell-level SRS is an interfering cell. The cell-level RSRP report may be sent from the interfered terminal to the interfered base station via upper signaling (e.g., RRC message). The cell-level RSRP report may be sent via the physical layer between the interfered base station and the interfered terminal. Since the FD system has a higher degree of terminal scheduling flexibility than the D-TDD system, the UE to UE CLI may have a greater degree of change than the D-TDD system. Therefore, in the FD system, the method of reporting the cell-level RSRP through the physical layer may be advantageous for a range with dynamic CLI changes compared to the method of reporting through upper layer signaling.

[0107] Figure 8 The order of cell-level CLI measurements according to various embodiments of the present disclosure is shown.

[0108] refer to Figure 8 , which can be described in Figure 7 The operation of selecting a terminal as an interfered terminal by a base station (eg, an interfered base station) during the cell-level CLI measurement process in FIG. Figure 7 The description in the description is repeated, and the reference Figure 7 The description is applicable to Figure 8 The chronological operations in .

[0109] In step 810, the victim terminal may receive information indicating that a CLI measurement operation is triggered from a base station. The victim terminal may receive information about a measurement object from the victim base station, and may initiate a CLI measurement operation by receiving the information about the measurement object.

[0110] In step 820, the interfered terminal may receive one or more cell-level SRSs from one or more interfering terminals (e.g., potential interfering terminals) located in a second cell adjacent to the first cell (e.g., one of a plurality of cells adjacent to the first cell). The one or more cell-level SRSs transmitted from the one or more potential interfering terminals located in the second cell may be transmitted through the same time and frequency resources according to the cell-level resource configuration information included in the information about the measurement object, and may have the same sequence.

[0111] In step 830, the interfered terminal may measure RSRP with respect to the cell-level SRS received from one or more potential interfering terminals located in the second cell, and may transmit a cell-level RSRP report including the measurement result to the base station.

[0112] Fig. 9 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown.

[0113] refer to Fig. 9 , a resource configuration method for enabling a potential interfering terminal to send a cell-level SRS to an interfered terminal may be described. All terminals located in cells adjacent to the cell where the interfered terminal is located may perform a cell-level SRS transmission process by sending the same sequence with respect to the same time and frequency resources for each cell. As used herein, the same sequence may also mean the same initial value for sequence generation of the SRS. Therefore, in order to send a cell-level SRS with respect to each adjacent cell, different cell-level SRS resources may be configured with respect to each cell. In order to configure different cell-level SRS resources with respect to each cell, the potentially interfering base station may exchange cell-specific SRS resource configuration information with the potentially interfering base station in the adjacent cell, thereby performing an inter-cell negotiation process.

[0114] In an embodiment, the potential interfering base station may allocate different cell-level SRS resources to each adjacent cell. Specifically, the potential interfering base station may configure the cell-level SRS resource configuration information for the potential interfering base station in the adjacent cell through upper layer signaling (e.g., RRC message). The potential interfering base station may configure the cell-level SRS resource configuration information in a dynamic method or a non-dynamic method.

[0115] According to the dynamic cell-level SRS resource configuration method, whenever the potential interfering base station sends a cell-level SRS, the potential interfering base station can configure the cell-level SRS resource configuration information for the potential interfering base station through inter-cell adjustment. Fig.11 According to the non-dynamic cell-level SRS resource configuration method, the potential interfering base station can configure the cell-level SRS resource configuration information for the potential interfering base station through the initial inter-cell adjustment, and the potential interfering base station in each adjacent cell can send the cell-level SRS to the interfered terminal through the resources configured for each adjacent cell. Fig.12 The detailed method is described. Meanwhile, the non-dynamic cell-level SRS resource configuration method may be more efficient than the dynamic cell-level SRS resource configuration method in terms of inter-cell signaling overhead.

[0116] The number of cell-level SRS resources configured for the adjacent cells may be the same as the number of adjacent cells, and the frequency resource reuse factor may be the same as the number of adjacent cells. The cell-level SRS resource configuration information may include information about at least one of a resource identifier (ID), a starting resource block (RB), an RB length, a comb factor (e.g., a factor for multiplexing multiple SRSs), a time slot / symbol index, a sequence ID, a time period, or a power. The resource ID may be configured differently for each adjacent cell. By exchanging cell-specific SRS resource configuration information between a potentially interfered base station and a potentially interfering base station in an adjacent cell, the potentially interfering base station in each adjacent cell may allocate the same cell-level SRS resources to a potentially interfering terminal located in the corresponding cell. In addition, the cell-level SRS resource configuration information may also include a flag for distinguishing from a UE-level SRS resource (e.g., a flag value of 0 indicates a cell-level SRS resource).

[0117] Fig.10 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown.

[0118] refer to Fig.10 , shows a method for enabling a potentially interfered base station to configure different cell-level SRS resource information for each cell with a potentially interfering base station in an adjacent cell. The potentially interfered base station can exchange cell-level SRS resource configuration information with a potentially interfering base station in an adjacent cell, and the same cell-level SRS resource can be allocated to a potentially interfering terminal located in the same adjacent cell through the cell-level SRS resource configuration information. Fig. 9 The descriptions made overlap the descriptions.

[0119] However, with Fig. 9 Different from the cell-level SRS resource configuration method in, the potentially interfered base station can configure the adjacent cells into groups, and the adjacent cell group can be understood below as including one or more adjacent cells in a logical sense. Therefore, the potentially interfered base station can configure the cell-level SRS resource configuration information about each adjacent cell group including one or more adjacent cells. For example, assuming that six adjacent cells are configured as adjacent cell groups including two adjacent cells, the potentially interfering terminals located in each cell group can send the same sequence to the interfered terminal through the same time and frequency resources. In addition, assuming that two adjacent cells constitute an adjacent cell group, the frequency resource reuse factor can be the same as the number of adjacent cell groups.

[0120] Fig.11 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown.

[0121] refer to Fig.11, a method for triggering the transmission of a cell-level SRS from each potentially interfering terminal to an interfered terminal in a non-periodic (or dynamic) manner may be described.

[0122] In step 1110, the cell-level SRS resource configuration information may be configured for the potential interfering terminal by exchanging the cell-level SRS resource configuration information between the potential interfered base station and the potential interfering base station.

[0123] In step 1120, the potentially interfered base station may instruct the potentially interfering base station to trigger the transmission of a cell-level SRS from the potentially interfering terminal through inter-cell signaling (eg, RRC message).

[0124] In step 1130, the potentially interfered base station may trigger the transmission of a cell-level SRS from the potentially interfering terminals located in the corresponding cell. For example, the potentially interfered base station may send a control message (e.g., downlink control information (DCI)) indicating the cell-level SRS transmission to each potentially interfering terminal through a control channel (e.g., a physical downlink control channel (PDCCH)).

[0125] In step 1140, after receiving a message indicating cell-level SRS transmission from the potential interfering base station, each potential interfering terminal may transmit a cell-level SRS to the interfered terminal through the cell-level SRS resources allocated for each cell.

[0126] After each potential interfering terminal sends a cell-level SRS to the interfered terminal, the above steps 1120 to 1140 may be repeated so that each potential interfering terminal sends a cell-level SRS to the interfered terminal. That is, whenever it is necessary to measure the RSRP about the cell-level SRS in order to determine the interfered terminal, the potential interfered base station may perform an inter-cell signaling operation (e.g., step 1120) with the potential interfering base station.

[0127] Fig.12 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown.

[0128] refer to Fig.12 , a method for triggering the transmission of cell-level SRS from various potential interfering terminals to the interfered terminal in a periodic or semi-periodic (or non-dynamic) manner may be described.

[0129] In step 1210, the cell-level SRS resource configuration information may be configured for the potential interfering base station by exchanging the cell-level SRS resource configuration information between the potential interfered base station and the potential interfering base station. The cell-level SRS resource configuration information may also include information on a cell-level SRS transmission period.

[0130] In step 1220, the potentially interfering base station may trigger the transmission of a cell-level SRS from a potentially interfering terminal located in the corresponding cell. For example, the potentially interfering base station may send configuration information related to cell-level SRS transmission to each potentially interfering terminal through an RRC message, thereby triggering cell-level SRS transmission (i.e., a periodic trigger type). Alternatively, the potentially interfering base station may send configuration information related to cell-level SRS transmission to each potentially interfering terminal through a medium access control (MAC) control element (CE), thereby triggering cell-level SRS transmission (i.e., a semi-periodic trigger type).

[0131] In step 1230, after receiving a message indicating cell-level SRS transmission from a potential interfering base station, each potential interfering terminal may send a cell-level SRS to an interfered terminal through a cell-level SERS resource allocated to each cell. Each potential interfering terminal may periodically send a cell-level SRS to an interfered terminal according to a cell-level SRS transmission period included in the cell-level SERS resource configuration information. Therefore, a potential interfered base station may trigger cell-level SRS transmission without separate inter-cell signaling.

[0132] Fig.13 A cell-level SRS transmission method according to various embodiments of the present disclosure is shown.

[0133] refer to Fig.13 , a cell-level SRS resource configuration method for enabling a potentially interfered terminal located in an adjacent cell to simultaneously measure CLI in a multi-cell environment may be described. Depending on the perspective, from the standpoint of a potentially interfered terminal located in an adjacent cell, a potentially interfered terminal may also be a potentially interfering terminal. Therefore, for CLI measurement, the potentially interfering terminal may simultaneously receive a cell-level SRS. Each potentially interfered terminal may therefore receive a cell-level SRS from a terminal located in other adjacent cells through resources allocated based on the cell-level SRS resource configuration information. In the case of resources allocated to a terminal located in a specific cell (e.g., a second cell), the terminal in the specific cell (e.g., the second cell) may not send a cell-level SRS for inter-cell CLI measurement.

[0134] Fig.14A A method for solving signal distortion according to various embodiments of the present disclosure is shown.

[0135] refer to Fig.14A, the problem of propagation delay that may occur when measuring RSRP with respect to cell-level SRSs simultaneously transmitted by potential interfering terminals located in respective adjacent cells may be described. With respect to respective potential interfering terminals that transmit cell-level SRSs, the distance to the serving base station (e.g., the potential interfering base station) and the distance to the interfered base station may be different. Therefore, even if the potential interfering terminal that transmits the cell-level SRS transmits the cell-level SRS by using the same time and frequency resources and by using the same sequence, the cell-level SRS received by the interfered terminal may be distorted, thereby reducing the correlation with the sequence during transmission. Therefore, the RSRP measurement with respect to the cell-level SRS is based on the autocorrelation of the SRS signal, and the accuracy of the RSRP measurement value may be reduced.

[0136] The propagation delay value can be defined by the following equation 1:

[0137] [Equation 1]

[0138] TUE1 + TV – TUE1,V

[0139] In Equation 1, TUE1 may refer to a propagation delay value between a first terminal (e.g., a potential interfering terminal located in one of a plurality of adjacent cells) and a target base station, TV may refer to a propagation delay value between an interfered terminal and an interfered base station, and TUE1,V may refer to a propagation delay value between the first terminal and the interfered base station.

[0140] In an embodiment for solving signal distortion caused by propagation delay, when sending a cell-level SRS, each potential interfering terminal may be sent the same SRS by TUEx before the existing transmission timing (e.g., the same SRS is sent earlier by TUEx). When configuring SRS resource configuration information for a potential interfering terminal, the potential interfering base station may also include a flag (e.g., a binary flag) for adjusting the transmission timing. For example, a flag value of 1 may indicate that the transmission is to be performed at the same transmission timing as the uplink data, because there is no problem of propagation delay caused by UE-level SRS transmission, and a flag value of 0 may indicate that the transmission is to be performed in advance by TUEx.

[0141] Fig. 14B A method for solving signal distortion according to various embodiments of the present disclosure is shown.

[0142] refer to Fig. 14B, an embodiment for solving signal distortion due to propagation delay may be described. In an embodiment, it is assumed that a potential interfering terminal that transmits the same cell-level SRS may transmit a cell-level SRS having the same sequence in different frequency bands in each cell. Assuming that signals in all frequency bands are received within a cyclic prefix (CP) even if the transmission timing is different in each frequency band, there may be no error in the RSRP measurement value regarding the cell-level SRS.

[0143] Assuming that the number of different frequency bands through which cell-level SRS is transmitted is N, the UE-specific transmit power can be reduced by 1 / N. However, when the interfered base station detects the interfering cell, the transmit power is reduced by 1 / N, and the threshold of RSRP may also need to be reduced by 1 / N. In addition, since the individual terminals do not have overlapping transmit signals, the received power can be the same as when a single terminal transmits, and since the transmit power is the same as the received power, the ADC saturation problem can also be solved. However, the available resource blocks (RBs) for assigning different frequency bands to individual terminals may be insufficient. For example, during RSRP measurement regarding cell-level SRS, the SRS size is 48RB, and even if the bandwidth is 100MHz (273RB), frequency division multiplexing (FDM) may only be possible for a maximum of five terminals.

[0144] Fig.15 A UE-level CLI measurement method according to various embodiments of the present disclosure is shown.

[0145] refer to Fig.15 , an operation flow between a base station and a terminal in a cell where the interfered terminal is located and in a cell identified as an interfering cell by the first step (e.g., a cell where an interfering base station and a potential interfering terminal are located). The interfered base station may share a UE-level SRS resource configuration with an interfering base station in a cell identified as an interfering cell by the first step. The SRS used to detect the channel state is only an example, and another RS ​​may be used. For example, a CLI measurement RS may be used. The CLI measurement RS may be an RS designed for UE-to-UE CLI measurement. The CLI measurement RS may be a signal for notifying a terminal sending an RS that the RS will be sent at a specific location on a resource grid based on the resource configuration of the base station. In addition, the CLI measurement RS may be a signal for notifying a terminal receiving the RS of a sequence for sending the RS based on the resource configuration of the base station. At the same time, in the absence of an interfering cell between adjacent cells, the interfered base station may not share a UE-level SRS resource configuration with the interfering base station.

[0146] In step (2-1), the interfering base station may trigger UE-level SRS transmission from a potential interfering terminal located in the corresponding cell based on the cell-level SRS resource configuration information shared with the interfered base station. If the UE-level SRS transmission is triggered by the interfering base station, the potential interfering terminal may send a UE-level SRS to the interfered terminal. In this case, the potential interfering terminal may send the UE-level SRS by sending the same sequence via the same time and frequency resources, or by sending different sequences via the same frequency resources.

[0147] In step (2-2), the interfered base station may send information about UE-specific measurement objects to the interfered terminal through upper layer signaling (e.g., RRC message). The information about the measurement object may include information about UE-level SRS resources to be sent by the potential interfering terminal. In addition, the interfered base station may trigger the RSRP measurement of the interfered terminal about the UE-level SRS through the information about the measurement object. For example, the interfered base station may send information about the measurement object to the interfered terminal, thereby instructing the interfered terminal to measure the RSRP about the UE-level SRS received from the potential interfering terminal. The interfered terminal may measure the RSRP about the UE-level SRS received from the potential interfering terminal. Since each potential interfering terminal sends different UE-level SRS resources and sequences, the interfered terminal may measure the heRSRP about the UE-level SRS with respect to each potential interfering terminal.

[0148] In addition, when further performing the intra-cell measurement operation, the interfered terminal may receive the UE-level SRS from the intra-cell potential interfering terminal (e.g., a terminal other than the interfered terminal in the first cell). The information about the measurement object may include information about the UE-level SRS resource to be sent by the intra-cell potential interfering terminal. In addition, the information about the measurement object may trigger the RSRP measurement of the UE-level SRS performed by the intra-cell potential interfering terminal.

[0149] In step (2-3), the interfered terminal may send a UE-level RSRP report obtained from the measurement about each potential interfering terminal to the interfered base station. The UE-level RSRP report may include an RSRP measurement value used by the interfered base station to determine the UE-level SRS of the interfering terminal among the potential interfering terminals. In an embodiment, the interfered terminal may report a pair of UE-level RSRP measurement values ​​and resource IDs (e.g., IDs of resources used to send UE-level SRS about each potential interfering terminal) to the interfered base station. In an embodiment, the interfered terminal may sort the resource IDs in descending order of the UE-level RSRP measurement values, and may report the resource IDs to the interfered base station. In an embodiment, the interfered terminal may select N (e.g., N is an integer equal to / greater than 1) resource IDs in descending order of the UE-level RSRP measurement values, and may report N pairs of resource IDs and RSRP measurement values ​​about the UE-level SRS to the interfered base station. In an embodiment, the interfered terminal may report a pair of resource IDs and RSRP measurement values ​​about the UE-level SRS to the interfered base station, and the RSRP measurement value about the UE-level SRS is equal to / greater than a specific threshold. In an embodiment, the interfered terminal may report a resource ID corresponding to an RSRP measurement value regarding a UE-level SRS to the interfered base station, the RSRP measurement value regarding the UE-level SRS being equal to / greater than a specific threshold.

[0150] The UE-level RSRP report may include an index (e.g., a threshold or a maximum value) used by the interfered base station to determine the interfering terminal. For example, upon receiving the UE-level RSRP report, the interfered base station may identify (or verify) that the corresponding interfering terminal is an interfering terminal when the UE-level SRS is greater than a certain threshold. The UE-level RSRP report may be sent from the interfered terminal to the interfered base station via upper layer signaling (e.g., an RRC message). Alternatively, the UE-level RSRP report may be sent via a physical layer between the interfered base station and the interfered terminal.

[0151] Fig.16 A method for configuring SRS resources at the UE level between cells according to various embodiments of the present disclosure is shown.

[0152] refer to Fig.16, UE-level SRS resource configuration information can be configured by sharing the SRS resource configuration between the interfered base station and the interfering base station, and the UE-level SRS resources can be configured not to overlap with the cell-level SRS resources. The SRS resource configuration information may include information about at least one of a resource ID, a starting RB, an RB length, a comb factor (e.g., a factor for multiplexing multiple SRSs), a time slot / symbol index, a sequence ID, a time period, or a power. The resource ID may be configured differently for each potential interfering terminal. In addition, the UE-level SRS resource configuration information may also include a flag for distinguishing from a cell-level SRS resource (e.g., a flag value of 1 indicates a UE-level SRS resource).

[0153] Meanwhile, the potentially interfered base station may need to configure the potentially interfering terminals into multiple terminal groups. Therefore, the potentially interfered base station may configure UE-level SRS resource configuration information differently for each terminal group, thereby saving resources compared to the case where UE-level SRS resources are configured for each potentially interfering terminal.

[0154] Fig.17 A method for configuring UE-level SRS resources within a cell according to various embodiments of the present disclosure is shown.

[0155] refer to Fig.17 , when performing intra-cell UE-to-UE CLI measurement, the interfered base station can configure resources for UE-level SRS transmission of the potential interfering terminal in the cell. The resources for UE-level SRS transmission of the potential interfering terminal in the cell can be configured for different time and frequency resources for each potential interfering terminal. In addition, the UE-level SRS sent by the potential interfering terminal in the cell can have different sequences.

[0156] Fig.18 A UE-to-UE CLI mitigation method according to various embodiments of the present disclosure is illustrated.

[0157] refer to Fig.18 , a scheduling method performed by an interfering base station after UE-to-UE CLI measurement is completed in order to mitigate interference with an interfering terminal may be described.

[0158] In step 1810, as an inter-cell CLI mitigation method, the interfered base station may send a message including identification information of the interfering terminal (eg, ID of the interfering terminal) and scheduling information of the interfered terminal to the interfering base station through an inter-base station interface (eg, Xn interface).

[0159] In step 1820, the interfered base station may send a message including the scheduling information of the interfered terminal to the interfering base station through an inter-base station interface (eg, an Xn interface).

[0160] In step 1830, the interfering base station may reschedule the interfering terminal based on the identification information of the interfering terminal and the scheduling information of the interfered terminal received from the interfered base station. For example, the interfering base station may schedule the interfering terminal so as not to perform uplink transmission when the interfered terminal receives downlink data.

[0161] However, the interfered base station may periodically measure the UE-level RSRP of the interfering terminal, and if the UE-level RSRP measurement value is less than the threshold value included in the UE-level SRS resource configuration information, the interfered base station may not change the scheduling of the interfering terminal. That is, the scheduling of the interfering terminal and the interfered terminal may be decoupled, and this may mean that the scheduling about the interfered terminal and the scheduling about the interfered terminal are performed independently without affecting each other.

[0162] At the same time, in order to mitigate intra-cell CLI interference, the interfered base station may reschedule the interfering terminal in the cell. For example, the interfered base station may schedule the interfering terminal so that the uplink transmission is not performed when the interfered terminal receives downlink data.

[0163] In addition to the above-mentioned scheduling change method, the interfering base station can also limit (or cancel) the scheduling of the interfering terminal. Alternatively, the interfering base station can limit the uplink transmission power of the interfering terminal. For example, the interfering base station can limit the transmission power so that the uplink signal from (one or more) interfering terminals is less than the threshold included in the UE-level SRS resource configuration information. Alternatively, the interfered base station can limit (or cancel) the scheduling of the interfered terminal.

[0164] Fig.19 A UE-to-UE CLI mitigation method according to various embodiments of the present disclosure is illustrated.

[0165] refer to Fig.19 , can describe a scheduling method performed by the interfered base station to reduce interference with the interfering terminal after the UE-to-UE CLI measurement is completed.

[0166] In step 1910, as an inter-cell CLI mitigation method, the interfered base station may send a message including identification information of the interfering terminal (eg, ID of the interfering terminal) and scheduling information of the interfered terminal to the interfering base station through an inter-base station interface (eg, Xn interface).

[0167] In step 1920, the interfering base station may send a message including the scheduling information of the interfering terminal to the interfering base station through an inter-base station interface (eg, an Xn interface).

[0168] In step 1930, the victim base station may schedule the victim terminal based on the scheduling information of the interfering terminal received from the interfering base station. For example, the victim base station may schedule the victim terminal so as not to receive downlink data when the interfering terminal sends uplink data.

[0169] However, the interfered base station may periodically measure the UE-level RSRP of the interfering terminal, and if the UE-level RSRP measurement value is less than the threshold value included in the UE-level SRS resource configuration information, the interfered base station may not change the scheduling of the interfered terminal. That is, the scheduling of the interfering terminal and the interfered terminal may be decoupled, and this may mean that the scheduling of the interfering terminal and the scheduling of the interfered terminal are performed independently without affecting each other.

[0170] At the same time, in order to mitigate intra-cell CLI interference, the interfered base station may reschedule the interfering terminal in the cell. For example, the interfered base station may schedule the interfering terminal so that the uplink transmission is not performed when the interfered terminal receives downlink data.

[0171] In addition to the above-mentioned scheduling change method, the interfering base station can also limit (or cancel) the scheduling of the interfering terminal. Alternatively, the interfering base station can limit the uplink transmission power of the interfering terminal. For example, the interfering base station can limit the transmission power so that the uplink signal from (one or more) interfering terminals is less than the threshold included in the UE-level SRS resource configuration information. Alternatively, the interfered base station can limit (or cancel) the scheduling of the interfered terminal.

[0172] Fig. 20 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0173] refer to Fig. 20 , the potential interfering base station may send a cell-level SRS to the interfered terminal so as to avoid only the potential interfering terminals located at the cell edge (or cell border), thereby saving resources for cell-level SRS transmission.

[0174] In step 2010, the potential interfering base station may configure information on resources used for cell-level SRS transmission for the potential interfering terminal.

[0175] In step 2020, if the potential interfering terminal enters the cell edge, the potential interfering base station may trigger cell-level SRS transmission from the potential interfering terminal. If the potential interfering terminal is located at the cell edge, the uplink signal from the potential interfering terminal may have less path loss than when the same uplink signal is located at the cell center, and thus the interfered terminal will experience a greater probability of interference. Therefore, the potential interfering base station may trigger cell-level SRS transmission only from the potential interfering terminal located at the cell edge.

[0176] In step 2030, if the potential interfering terminal enters the cell center, the potential interfering base station may instruct the potential interfering terminal not to send a cell-level SRS. This is because if the potential interfering terminal is located at the cell center, the uplink signal from the potential interfering terminal has a large path loss, and therefore the possibility that the interfered terminal will experience interference may be small.

[0177] In the above steps 2020 and 2030, in order to determine the location of the terminal (e.g., whether the terminal is located at the center of the cell or at the edge of the cell), the potential interfering base station may compare the measurement value (e.g., CQI, RSRP of CSI-RS, or timing advance (TA)) received from the potential interfering terminal with a specific threshold (e.g., CQI, RSRP of CSI-RS, or threshold of TA). For example, if the CQI measured by the potential interfering terminal is greater than a specific threshold (e.g., CQI threshold) included in the information about the resources used for cell-level SRS transmission, the potential interfering base station may determine that the potential interfering terminal is located at the center of the cell. Alternatively, if the CQI measured by the potential interfering terminal is equal to or less than a specific threshold (e.g., CQI threshold) included in the information about the resources used for cell-level SRS transmission, the potential interfering base station may determine that the potential interfering terminal is located at the edge of the cell.

[0178] However, in addition to the location of the potential interfering terminal, the potential interfering base station may also additionally consider the downlink beam index. For example, as long as the potential interfering terminal receives a downlink signal with a specific downlink beam index, the potential interfering base station may instruct the potential interfering terminal (even if located at the cell edge) not to send a cell-level SRS.

[0179] Fig.21 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0180] refer to Fig.21 , the potential interfering base station may send a cell-level SRS only to the potential interfering terminals located at the cell edge (as the interfered terminals), thereby saving resources for cell-level SRS transmission.

[0181] In step 2110, the potential interfering base station may configure information on resources used for cell-level SRS transmission for the potential interfering terminal.

[0182] In step 2120, the potential interfering base station may configure the potential interfering terminal with information including an index (eg, CQI, RSRP of CSI-RS, or TA threshold) used by the potential interfering terminal to determine whether to send a cell-level SRS according to its location.

[0183] In step 2130, if the potential interfering terminal enters the cell edge, the potential interfering terminal may send a cell-level SRS to the potential interfering base station.

[0184] In step 2140, if the potential interfering terminal enters the cell center, the potential interfering terminal may instruct the potential interfering base station not to send a cell-level SRS.

[0185] For example, in the above steps 2120 and 2130, if the CQI measured by the potential interference terminal is greater than a specific threshold (e.g., CQI threshold) included in the information about the resources for cell-level SRS transmission, the potential interference terminal may be considered to be located at the center of the cell. Alternatively, if the CQI measured by the potential interference terminal is equal to or less than a specific threshold (e.g., CQI threshold) included in the information about the resources for cell-level SRS transmission, the potential interference terminal may be considered to be located at the edge of the cell.

[0186] However, in addition to the location of the potential interfering terminal, the potential interfering terminal may additionally consider the downlink beam index. For example, as long as the potential interfering terminal receives a downlink signal with a specific downlink beam index, the potential interfering base station may not send a cell-level SRS to the potential interfering terminal, even if the potential interfering terminal is located at the cell edge.

[0187] Fig. 22 A table showing mapping between cell IDs and SRS resources according to various embodiments of the present disclosure.

[0188] refer to Fig. 22 , a cell-level SRS transmission method can be described by a table of mappings between cell IDs and cell-level and SRS resources preconfigured for potential interfering terminals. The potential interfering base station can configure a table of mappings between cell IDs and SRS resources for the potential interfering terminal in advance. Therefore, even if the potential interfering base station only sends cell ID-related information to the potential interfering terminal, the potential interfering terminal can also send a cell-level SRS to the interfered terminal based on the preconfigured mapping table. That is, even if the interfered base station only sends the cell ID of the neighboring cell to the interfered terminal, the interfered terminal can also measure the RSRP of the cell-level SRS sent by the potential interfering terminal included in the neighboring cell corresponding to the cell ID.

[0189] Therefore, with the reference above Fig. 9 Unlike the non-dynamic cell-level SRS resource configuration method described above, the adjustment process between the interfered base station and the potential interfering base station (e.g., step 1210) and the signaling process from the potential interfering base station to the potential interfering terminal (e.g., step 1220) may be unnecessary. Fig. 22According to the scheme proposed in , it may be necessary to distribute physical cell IDs (PCIs) so that the resources used for cell-level SRS transmission do not overlap between neighboring cells.

[0190] Fig.23 A method for measuring RSRP with respect to a cell-level SRS according to various embodiments of the present disclosure is illustrated.

[0191] refer to Fig.23 , which can be described by combining Figure 7 In step (1-2) of the method, the interfered base station preconfigures information about the measurement object instead of sending it to the interfered terminal every time CLI measurement is required, so that the interfered terminal can determine whether to measure CLI by itself. Fig.23 The left flow chart in Fig.15 In the process of step (2-2) in FIG. 1 , the interfered base station may send information about the measurement object so that the interfered terminal measures the RSRP about the cell-level SRS. Meanwhile, in another embodiment, referring to Fig.23 As shown in the right flow chart in FIG. 1 , the potentially interfered base station can preconfigure information about the measurement object so that the potentially interfered terminal can determine the CLI measurement by itself without its transmission.

[0192] Specifically, the potentially interfered base station can pre-configure cell-level SRS resource configuration information for the potentially interfered terminal through upper layer signaling (e.g., "measObjectCLI" in the information element (IE) of the RRC message). The cell-level SRS resource configuration information may include information about the configuration of cell-level SRS resources for all cells. The potentially interfered terminal can self-trigger whether to measure CLI based on CSI-RS related feedback information (e.g., CQI). If the potentially interfered terminal determines CLI measurement, the potentially interfered terminal can be considered as an interfered terminal. Therefore, the interfered base station may not perform a process for sending information about the measurement object used for CLI measurement to the terminal considered to be the interfered terminal. Therefore, the overhead caused by signaling (e.g., transmission of measurement object related information) between the interfered base station and the interfered terminal can be reduced.

[0193] Fig.24 A method for measuring RSRP with respect to a cell-level SRS according to various embodiments of the present disclosure is illustrated.

[0194] In the following, references to Fig.23 The descriptions made overlap the descriptions.

[0195] refer to Fig.24, the interfered base station that has determined the CLI measurement can send a message including a CLI measurement notification to the interfered base station before measuring the RSRP for the cell-level SRS. The interfered terminal cannot send and / or receive signals with the interfered base station when measuring the CLI, and the interfered base station can therefore be notified of the CLI measurement in advance before measuring the RSRP for the cell-level SRS so that the interfered base station can adjust the scheduling for the interfered terminal. Upon receiving the cell-level RSRP report from the interfered terminal, the interfered base station can determine that the CLI measurement is completed.

[0196] Fig.25 It is shown how RSRP measurement error (underestimation) occurs according to various embodiments of the present disclosure.

[0197] refer to Fig.25 , when the victim terminal uses the cell-level SRS for intra-cell CLI measurement, the victim terminal may only receive the cell-level SRS of the potential interfering terminal located in the neighboring cell without transmitting the cell-level SRS. Therefore, when multiple terminals simultaneously measure the cell-level CLI in a multi-cell environment, RSRP measurement errors may occur due to the terminals that do not transmit the cell-level SRS. A scheme for compensating for such errors is necessary to improve the accuracy of the CLI measurement results, and will now be referred to Fig.26 Describes a detailed scheme for compensating for errors through measurement performance improvement.

[0198] Fig.26 A method for resolving RSRP measurement errors according to various embodiments of the present disclosure is shown.

[0199] refer to Fig.26 , which can be described to solve Fig.25 A cell-level SRS resource configuration method for RSRP measurement errors in the cell. The potentially interfered base station can configure the cell-level SRS resources for intra-cell CLI measurement separately from the cell-level SRS resources for inter-cell CLI measurement. Therefore, each terminal can send the cell-level SRS resources for inter-cell CLI measurement regardless of the intra-cell CLI measurement, and the measurement error problem will not occur in the cell-level SRS resource area for inter-cell CLI measurement. However, when multiple terminals in a single cell measure intra-cell CLI by using cell-level SRS at the same time, the measurement error problem may still occur in the cell-level SRS resource area for intra-cell CLI measurement.

[0200] Fig. 27 A method for resolving RSRP measurement errors according to various embodiments of the present disclosure is shown.

[0201] refer to Fig. 27, assuming that the intra-cell CLI is measured by using the cell-level SRS simultaneously in a single cell, the number of terminals measuring the intra-cell CLI can be limited. For example, if the number of terminals measuring the intra-cell CLI is limited to one, the base station can adjust the measurement order of the terminals that simultaneously receive the cell-level SRS, thereby configuring the SRS resources so that two or more terminals cannot measure the intra-cell CLI by using the cell-level SRS simultaneously. Through the above method, even if the intra-cell CLI is measured by using the cell-level SRS, the measurement error problem will not occur. However, it may be difficult for the terminal to determine the cell-specific cell-level CLI measurement order.

[0202] For inter-base station adjustment, it may be necessary to exchange information about the configuration of cell-level SRS resources for intra-cell CLI measurement. Therefore, the information about the configuration of cell-level SRS resources may also include a flag (e.g., a binary flag) for distinguishing cell-level SRS resources for inter-cell CLI measurement and cell-level SRS resources for intra-cell CLI measurement. For example, a flag value of 0 may indicate a cell-level SRS resource for inter-cell CLI measurement, and a flag value of 1 may indicate a cell-level SRS resource for intra-cell CLI measurement.

[0203] Fig.28 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0204] refer to Fig.28 For intra-cell CLI measurement, terminals other than terminals located at the cell edge may need to send cell-level SRS. However, terminals located at the cell center are not affected by inter-cell CLI, and therefore intra-cell CLI measurement can be performed by using UE-level SRS of intra-cell terminals instead of measuring inter-cell CLI by using cell-level SRS. In addition, terminals located at the cell center do not interfere with terminals located at the cell edge in the cell, and cell-level SRS may not be sent.

[0205] Fig.29 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0206] refer to Fig.29 , can be used to distinguish the above reference Fig.28The method described is that the cell-level SRS transmission is unnecessary for the area. A specific cell may be divided into a first area (e.g., cell edge), a second area (e.g., cell middle), and a third area (e.g., cell center), and the criterion for division may be at least one of CQI, RSRP of CSI-RS, or TA. Considering the intra-cell CLI, the first area, the second area, and the third area may cause interference with each other, but the first area and the third area may hardly cause interference with each other. Therefore, the terminal in the first area may send a cell-level SRS, but the terminal in the third area may not send a cell-level SRS. At the same time, the terminal in the second area may cause the intra-cell CLI in the first area, the terminal in the first area may need a cell-level CLI measurement, and the terminal in the second area may therefore need to send a cell-level SRA for intra-cell CLI measurement. However, the terminal in the second area may not send a cell-level SRS for inter-cell CLI measurement. In short, the terminal in the third area may not send a cell-level SRS, and the overhead caused by the cell-level SRS transmission may be reduced by not sending a cell-level SRS.

[0207] Fig.30 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0208] refer to Fig.30 , a method for triggering cell-level SRS transmission in an aperiodic (or dynamic) manner may be described, assuming that the area within the cell is divided into a first area to a third area, as described above with reference to Fig.29 described.

[0209] In step 3010, the cell-level SRS resource configuration information may be configured for the potential interfering base station by exchanging the cell-level SRS resource configuration information between the potential interfered base station and the potential interfering base station.

[0210] In step 3020, if the potential interfering terminal enters the first area, the potential interfering base station may trigger transmission of a cell-level SRS (eg, a cell-level SRS for intra-cell CLI measurement and a cell-level SRS for inter-cell CLI measurement) from the potential interfering terminal.

[0211] In step 3030, if the potential interfering terminal enters the second area, the potential interfering base station may trigger transmission of a cell-level SRS (eg, a cell-level SRS for intra-cell CLI measurement) from the potential interfering terminal.

[0212] In step 3040, if the potential interfering terminal enters the third area, the potential interfering base station may instruct the potential interfering terminal not to send a cell-level SRS.

[0213] Fig.31 A method for transmitting a cell-level SRS in consideration of a location of a terminal according to various embodiments of the present disclosure is illustrated.

[0214] refer to Fig.31 , a method for triggering cell-level SRS transmission in a periodic or semi-periodic (or non-dynamic) manner may be described, assuming that the area within the cell is divided into a first area to a third area, as described above with reference to Fig.29 described.

[0215] In step 3110, the cell-level SRS resource configuration information may be configured for the potential interfering base station by exchanging the cell-level SRS resource configuration information between the potential interfered base station and the potential interfering base station.

[0216] In step 3120, the potentially interfering base station may configure

[0217] Includes information used by the potential interfering terminal to determine whether to send a cell-level SRS index (eg, CQI, RSRP of CSI-RS, or TA threshold) according to its location through upper layer signaling (eg, RRC message).

[0218] In step 3130, if the potential interfering terminal enters the first area, the potential interfering terminal may send a cell-level SRS (eg, a cell-level SRS for intra-cell CLI measurement and a cell-level SRS for inter-cell CLI measurement) to the potential interfering terminal.

[0219] In step 3140, if the potential interfering terminal enters the second area, the potential interfering terminal may send a cell-level SRS (eg, a cell-level SRS for intra-cell CLI measurement) to the potential interfering terminal.

[0220] In step 3150, if the potential interfering terminal enters the third area, the potential interfering terminal may not send a cell-level SRS to the potential interfering base station.

[0221] Fig.32 A mapping table of SRS resources for intra-cell and inter-cell CLI measurements according to various embodiments of the present disclosure is shown.

[0222] This can be omitted and referenced Fig. 22 The descriptions made overlap the descriptions.

[0223] refer to Fig.32 , can be described according to the above reference Fig.26 or Fig. 27The method for configuring cell-level SRS resources for intra-cell measurement and cell-level SRS resources for inter-cell measurement in the described embodiments. The potential interfering terminal can send a cell-level SRS (e.g., cell-level SRS resources for intra-cell measurement and cell-level SRS resources for inter-cell measurement) to the interfered terminal based on a pre-configured table of mappings between cell IDs and cell-level SRS resources.

[0224] Fig.33 An intra-cell CLI measurement method according to various embodiments of the present disclosure is illustrated.

[0225] refer to Fig.33 , which can describe the operation of a potentially interfered terminal determining measurements within a cell.

[0226] In step 3310, for intra-cell CLI measurement, the interfered base station may pre-configure information of the interfered terminal so that the interfered terminal can determine whether to measure CLI by itself.

[0227] In step 3320, the potential interfered terminal may determine whether to measure CLI based on feedback information (eg, CQI) about the CSI-RS. If the potential interfered terminal determines to measure CLI, the potential interfered terminal may be considered as an interfered terminal.

[0228] In step 3330, the victim terminal may determine to measure the intra-cell CLI. In step 3340, the victim terminal may send a message including an intra-cell CLI measurement request to the victim base station.

[0229] In step 3350, the interfered base station may refer to a specific threshold value to determine whether to send authorization for intra-cell CLI measurement. Specifically, if the count of the interfered terminal is less than the specific threshold value, the interfered base station may send authorization for intra-cell CLI measurement to the interfered terminal. Alternatively, if the count of the interfered terminal is equal to the above-mentioned specific threshold value, the interfered base station may not send authorization for intra-cell CLI measurement to the interfered terminal. The interfered terminal may again send a message including an intra-cell CLI measurement request to the interfered base station, and the interfered base station may again refer to the specific threshold value to determine whether to send authorization for intra-cell CLI measurement.

[0230] In step 3360, the victim terminal may measure the intra-cell CLI according to the intra-cell CLI measurement grant (eg, receive a cell-level SRS from an intra-cell potential interfering terminal and measure RSRP with respect to the cell-level SRS). The victim base station may increase the count of the victim terminal by 1.

[0231] In step 3370, the interfered terminal may send a cell-level RSRP report to the interfered base station.

[0232] In step 3380, the interfered base station may reduce the count of total interfered terminals by 1 upon receiving the measurement result from the interfered terminal.

[0233] Fig.34 An intra-cell CLI measurement method according to various embodiments of the present disclosure is illustrated.

[0234] refer to Fig.34 , which can describe the operation of a potentially interfered terminal determining measurements within a cell.

[0235] In step 3410, for intra-cell CLI measurement, the interfered base station may pre-configure information of the interfered terminal so that the interfered terminal can determine whether to measure CLI by itself.

[0236] In step 3420, the potential victim terminal may determine whether to measure CLI based on feedback information (eg, CQI) about the CSI-RS. If the potential victim terminal determines to measure CLI, the potential victim terminal may be considered as an interfered terminal.

[0237] In step 3430, the interfered terminal may determine the CLI in the measurement cell.

[0238] In step 3440, the interfered terminal may send a message including an intra-cell CLI measurement request to the interfered base station.

[0239] In step 3450, instead of sending the authorization for intra-cell CLI measurement to the victim terminal, the victim base station may send a flag (e.g., a binary flag). For example, if the count of the victim terminal is less than a specific threshold, the victim base station may send a flag value configured as 0 to the victim terminal. Alternatively, if the count of the victim terminal is equal to the above-mentioned specific threshold, the victim base station may send a flag value configured as 1 to the victim terminal. When the victim terminal again sends a message including an intra-cell CLI measurement request to the victim base station, the victim base station may again perform an operation for determining the flag value with reference to the specific threshold.

[0240] In step 3460, the victim terminal may measure the intra-cell CLI according to the intra-cell CLI measurement grant (eg, receive a cell-level SRS from an intra-cell potential interfering terminal and measure RSRP with respect to the cell-level SRS). The victim base station may increase the count of the victim terminal by 1.

[0241] In step 3470, the interfered terminal may send a cell-level RSRP report to the interfered base station.

[0242] In step 3480, the interfered base station may reduce the count of total interfered terminals by 1 upon receiving the measurement result from the interfered terminal.

[0243] Fig.35 A method for addressing ADC saturation according to various embodiments of the present disclosure is shown.

[0244] refer to Fig.35 , the cell-level SRS transmitted from a potential interfering terminal located on one neighboring cell has the same sequence in the same time and frequency resources, and the received power in the interfered terminal may be increased compared with the UE-level SRS.

[0245] In an embodiment, if there is one potential interfering terminal among the potential interfering terminals that has a dominant impact on the interfered terminal, the impact on the received power from the remaining potential interfering terminals may be insignificant. Therefore, there may be a negligible difference in received power between the cell-level SRS and the UE-level SRS.

[0246] In an embodiment, if there are a plurality of potential interfering terminals having a dominant influence on the interfered terminal among the potential interfering terminals, the cell-level SRS may have a large difference in received power compared to the UE-level SRS.

[0247] Therefore, assuming that the interfered terminal has a reception gain according to the reception configuration of the UE-level SRS, if the cell-level SRS is received without changing the reception gain, ADC saturation may occur.

[0248] If a cell-level SRS is periodically transmitted from a potential interference terminal, the victim terminal may measure RSRP with respect to the cell-level SRS. If ADC saturation occurs in this case, the victim terminal may adjust the reception gain (e.g., reduce the reception gain). The victim terminal may repeat the operation of adjusting the reception gain according to RSRP measurement with respect to the cell-level SRS until ADC saturation does not occur.

[0249] Fig.36 A method for addressing ADC saturation according to various embodiments of the present disclosure is shown.

[0250] This can be omitted and referenced Fig.35 The descriptions made overlap the descriptions.

[0251] refer to Fig.36 If ADC saturation occurs, the victim terminal may send an ADC saturation report to the victim base station. The victim base station may then consider that CLI occurs in the cell that causes ADC saturation (e.g., consider that the cell that causes ADC saturation is an interfering cell), and may perform a UE-level CLI measurement procedure with the victim terminal (e.g., Fig.15in the regulations).

[0252] Fig.37 An interfering cell detection method according to various embodiments of the present disclosure is shown.

[0253] refer to Fig.37 , the interfered terminal may measure only the cell-level CLI for some of the neighboring cells, and may measure only the UE-level CLI for the remaining neighboring cells without measuring the cell-level CLI. For example, the interfered terminal may immediately measure the RSRP for the UE-level SRS for the cell most adjacent to the interfered terminal (e.g., the cell with the highest probability that UE-to-UE CLI will occur) without measuring the RSRP for the cell-level SRS, and may measure the RSRP for the cell-level SRS for other neighboring cells. Therefore, the number of times the RSRP is measured for the cell-level SRS can be reduced, and the delay can be reduced during the entire RSRP measurement process because the number of times the RSRP is measured for the cell-level SRS is reduced.

[0254] As described above, the method for operating a terminal in a wireless communication system according to various embodiments disclosed herein may include: a step of receiving information indicating that a cross link interference (CLI) measurement is triggered by selecting the terminal as an interfered terminal from a base station, after the CLI measurement is triggered, a step of receiving one or more cell-level reference signals (RS) from one or more terminals in a second cell adjacent to a first cell where the terminal is located, a cell-level measurement report, the cell-level measurement report including a result of measuring a reference signal received power (RSRP) of the received one or more cell-level RSs. The one or more cell-level RSs may be received in the same sequence on the same radio resource.

[0255] According to various embodiments disclosed herein, the method for operating a terminal may also include the following steps: in a case where a second cell is selected as an interfering cell based on a cell-level measurement report, receiving one or more UE-level RSs from one or more terminals in the second cell, and sending a UE-level measurement report to a base station, the UE-level measurement report including the result of measuring the RSRP of the received one or more UE-level RSs.

[0256] According to various embodiments disclosed herein, the method for operating a terminal may also include the following steps: in a case where one or more interfering terminals are selected from one or more terminals in a second cell based on a UE-level measurement report, receiving scheduling information from a base station in view of a CLI configuration with the one or more interfering terminals, and performing uplink transmission to the base station based on the scheduling information.

[0257] According to various embodiments disclosed herein, cell-level RSs received from a plurality of cells adjacent to a first cell may be different from each other with respect to the plurality of cells, respectively.

[0258] According to various embodiments disclosed herein, the information indicating that the CLI measurement is triggered may include a measurement object message, and the measurement object messages may respectively include information on transmission resources of a cell-level RS.

[0259] As described above, the method for operating a base station in a wireless communication system according to various embodiments disclosed herein may include the following steps: in a case where channel quality information included in a channel state information (CSI) report received from the terminal is less than a first threshold, selecting the terminal as an interfered terminal, sending information indicating that CLI measurement is triggered to the interfered terminal, receiving a cell-level measurement report from the terminal, the cell-level measurement report including a result of measuring the reference signal received power (RSRP) of multiple cell-level reference signals (RS) of multiple cells adjacent to a first cell where the terminal is located after the CLI measurement is triggered, and selecting a cell corresponding to an RSRP equal to / higher than a second threshold as an interfering cell based on the cell-level measurement report. Multiple cell-level RSs may be sent in the same sequence on the same radio resource, and the first threshold and the second threshold may be different from each other.

[0260] According to various embodiments disclosed herein, the method for operating a base station may further include the step of receiving a UE-level measurement report from a terminal including the result of measuring the RSRP of one or more UE-level RSs of an interfering cell, and the step of selecting a terminal corresponding to an RSRP equal to / higher than a third threshold as an interfering terminal based on the UE-level measurement report.

[0261] According to various embodiments disclosed herein, the method for operating a base station may also include the following steps: in a case where one or more interfering terminals are selected based on a UE-level measurement report, sending scheduling information to the terminal in view of the CLI configuration with the one or more interfering terminals, and receiving uplink data from the terminal based on the scheduling information.

[0262] According to various embodiments disclosed herein, cell-level RSs received from a plurality of cells adjacent to a first cell may be different from each other with respect to the plurality of cells, respectively.

[0263] According to various embodiments disclosed herein, the information indicating that the CLI measurement is triggered may include a measurement object message, and the measurement object messages may respectively include information on transmission resources of a cell-level RS.

[0264] As described above, a terminal device in a wireless communication system according to various embodiments disclosed herein may include a transceiver, a memory, and a controller. The controller may receive information indicating that a cross-link interference (CLI) measurement is triggered by selecting a terminal as an interfered terminal from a base station, may receive one or more cell-level reference signals (RS) from one or more terminals in a second cell adjacent to a first cell where the terminal is located after the CLI measurement is triggered, and may send a cell-level measurement report to the base station, the cell-level measurement report including a result of measuring a reference signal received power (RSRP) of one or more received cell-level RSs. One or more cell-level RSs may be received in the same sequence on the same radio resource.

[0265] According to various embodiments disclosed herein, the controller may receive one or more UE-level RSs from one or more terminals in the first cell, and may send a UE-level measurement report including a result of measuring the RSRP of the received one or more UE-level RSs to the base station. The one or more terminals in the first cell may be the remaining terminals other than the terminal in the first cell.

[0266] According to various embodiments disclosed herein, in the case where a second cell is selected as an interfering cell, the controller may receive scheduling information based on a cell-level measurement report from a base station in view of a CLI configuration with one or more terminals located in the second cell, and may perform uplink transmission to the base station based on the scheduling information.

[0267] According to various embodiments disclosed herein, cell-level RSs received from a plurality of cells adjacent to a first cell may be different from each other with respect to the plurality of cells, respectively.

[0268] According to various embodiments disclosed herein, the information indicating that the CLI measurement is triggered may include a measurement object message, and the measurement object messages may respectively include information on transmission resources of a cell-level RS.

[0269] As described above, a base station device in a wireless communication system according to various embodiments disclosed herein may include a transceiver, a memory, and a controller. In the case where the channel quality information included in the channel state information (CSI) report received from the terminal is less than the first threshold, the controller may select the terminal as an interfered terminal, may send information indicating that the CLI measurement is triggered to the interfered terminal, may receive a cell-level measurement report from the terminal, the cell-level measurement report including the result of measuring the reference signal received power (RSRP) of multiple cell-level reference signals (RS) of multiple cells adjacent to the first cell where the terminal is located after the CLI measurement is triggered, and may select a cell corresponding to an RSRP equal to / higher than the second threshold as an interfering cell based on the cell-level measurement report. Multiple cell-level RSs may be sent in the same sequence on the same radio resource, and the first threshold and the second threshold may be different from each other.

[0270] According to various embodiments disclosed herein, the controller may receive a UE-level measurement report including the results of measuring the RSRP of one or more UE-level RSs of an interfering cell from a terminal, and may select a terminal corresponding to an RSRP equal to / higher than a third threshold as an interfering terminal based on the UE-level measurement report.

[0271] According to various embodiments disclosed herein, in the case of selecting one or more interfering terminals based on UE-level measurement reports, the controller may send scheduling information to the terminal in view of the CLI configuration with the one or more interfering terminals, and may receive uplink data from the terminal based on the scheduling information.

[0272] According to various embodiments disclosed herein, cell-level RSs received from a plurality of cells adjacent to a first cell may be different from each other with respect to the plurality of cells, respectively.

[0273] According to various embodiments disclosed herein, the information indicating that the CLI measurement is triggered may include a measurement object message, and the measurement object messages may respectively include information on transmission resources of a cell-level RS.

[0274] The methods according to the embodiments described in the claims or specification of the present disclosure may be implemented in software, hardware, or a combination of hardware and software.

[0275] As for software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors of an electronic device. One or more programs may include instructions for controlling an electronic device to perform a method according to an embodiment described in the claims or specification of the present disclosure.

[0276] Such a program (software module, software) may be stored in a random access memory, a non-volatile memory including flash memory, a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), a magnetic disk storage device, a compact disk (CD)-ROM, a digital versatile disk (DVD) or other optical storage device, and a magnetic tape cassette. Alternatively, it may be stored in a memory combining part or all of those recording media. A plurality of memories may be included.

[0277] In addition, the program may be stored in an attachable storage device that is accessible via a communication network such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN), or a storage area network (SAN), or a communication network that combines these networks. Such a storage device may access the device that performs the embodiments of the present disclosure through an external port. In addition, a separate storage device on a communication network may access the device that performs the embodiments of the present disclosure.

[0278] In the specific embodiments of the present disclosure, the components included in the present disclosure are expressed in singular or plural form. However, for ease of explanation, singular or plural expression is appropriately selected according to the situation presented, and the present disclosure is not limited to a single component or multiple components, and a component expressed in plural form can be configured as a single component, and a component expressed in singular form can be configured as multiple components.

[0279] Meanwhile, although specific embodiments have been described in the explanation of the present disclosure, it should be noted that various changes may be made therein without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure is not limited or defined by the described embodiments, and is limited not only by the scope of the following claims, but also by their equivalents.

[0280] Although the present disclosure has been described with various embodiments, various changes and modifications may be suggested to one skilled in the art. The present disclosure is intended to encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: receiving, from a base station, information indicating that a cross-link interference (CLI) measurement is triggered when the UE is identified as an interfered UE; After the CLI measurement is triggered, receiving one or more cell-level reference signals (RS) from one or more UEs in a second cell adjacent to a first cell where the UE is located; as well as sending a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of one or more received cell-level RSs to a base station, Therein, one or more cell-level RSs are received in the same sequence on the same radio resource.

2. The method according to claim 1, further comprising: receiving one or more UE-level RSs from one or more UEs in the second cell in a case where the second cell is identified as an interfering cell based on the cell-level measurement report; as well as A UE-level measurement report including a result of measuring the RSRP of the received one or more UE-level RSs is transmitted to the base station.

3. The method according to claim 2, further comprising: receiving, from the base station, scheduling information in view of the CLI configuration with the one or more interfering UEs in a case where one or more interfering UEs are identified from the one or more UEs in the second cell based on the UE-level measurement report; as well as Uplink transmission to the base station is performed based on the scheduling information.

4. The method according to claim 1, wherein: The cell-level RSs received from a plurality of cells adjacent to the first cell are different from each other with respect to the plurality of cells, respectively.

5. A method performed by a base station in a wireless communication system, the method comprising: In a case where channel quality information included in a channel state information (CSI) report received from a user equipment (UE) is less than a first threshold, identifying the UE as an interfered UE; Sending information indicating that CLI measurement is triggered to the interfered UE; After the CLI measurement is triggered, receiving, from the UE, a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of a plurality of cell-level reference signals (RSs) of a plurality of cells adjacent to a first cell in which the UE is located; as well as identifying a cell corresponding to an RSRP greater than or equal to a second threshold as an interfering cell based on the cell-level measurement report, Wherein, a plurality of cell-level RSs are transmitted in the same sequence on the same radio resource, and the first threshold and the second threshold are different from each other.

6. The method according to claim 5, further comprising: receiving, from the UE, a UE-level measurement report including a result of measuring RSRP of one or more UE-level RSs of an interfering cell; as well as A UE corresponding to an RSRP greater than or equal to a third threshold is identified as an interfering UE based on the UE-level measurement report.

7. The method according to claim 6, further comprising: In a case where one or more interfering UEs are identified based on the UE-level measurement report, sending scheduling information to the UE in view of the CLI configuration with the one or more interfering UEs; as well as Uplink data is received from the UE based on the scheduling information.

8. The method according to claim 5, wherein: The cell-level RSs received from a plurality of cells adjacent to the first cell are different from each other with respect to the plurality of cells, respectively.

9. A user equipment (UE) in a wireless communication system, the UE comprising: Transceiver; as well as At least one processor is coupled to the transceiver and is configured to: receiving, from a base station, information indicating that a cross-link interference (CLI) measurement is triggered when the UE is identified as an interfered UE; After the CLI measurement is triggered, receiving one or more cell-level reference signals (RS) from one or more UEs in a second cell adjacent to a first cell where the UE is located; and transmitting a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of one or more received cell-level RSs to a base station, and Therein, one or more cell-level RSs are received in the same sequence on the same radio resource.

10. The UE according to claim 9, wherein: The at least one processor is further configured to: receiving one or more UE-level RSs from one or more UEs in the second cell in a case where the second cell is identified as an interfering cell based on the cell-level measurement report; and A UE-level measurement report including a result of measuring the RSRP of the received one or more UE-level RSs is transmitted to the base station.

11. The UE according to claim 10, wherein: The at least one processor is configured to: receiving, from the base station, scheduling information in view of the CLI configuration with the one or more interfering UEs in a case where one or more interfering UEs are identified from the one or more UEs in the second cell based on the UE-level measurement report; and Uplink transmission to the base station is performed based on the scheduling information.

12. The UE according to claim 9, wherein: The cell-level RSs received from a plurality of cells adjacent to the first cell are different from each other with respect to the plurality of cells, respectively.

13. A base station in a wireless communication system, the base station comprising: Transceiver; as well as At least one processor is coupled to the transceiver and is configured to: In a case where channel quality information included in a channel state information (CSI) report received from a user equipment (UE) is less than a first threshold, identifying the UE as an interfered UE; Sending information indicating that CLI measurement is triggered to the interfered UE; After the CLI measurement is triggered, receiving, from the UE, a cell-level measurement report including a result of measuring a reference signal received power (RSRP) of a plurality of cell-level reference signals (RSs) of a plurality of cells adjacent to a first cell in which the UE is located; and identifying a cell corresponding to an RSRP greater than or equal to a second threshold as an interfering cell based on the cell-level measurement report, and Wherein, a plurality of cell-level RSs are transmitted in the same sequence on the same radio resource, and the first threshold and the second threshold are different from each other.

14. The base station according to claim 13, wherein: The at least one processor is configured to: receiving, from the UE, a UE-level measurement report including a result of measuring RSRP of one or more UE-level RSs of an interfering cell; and A UE corresponding to an RSRP greater than or equal to a third threshold is identified as an interfering UE based on the UE-level measurement report.

15. The base station according to claim 14, wherein: The at least one processor is configured to: In a case where one or more interfering UEs are identified based on the UE-level measurement report, sending scheduling information to the UE in view of the CLI configuration with the one or more interfering UEs; and Uplink data is received from the UE based on the scheduling information.

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