Method and radio access network node

Abstract

A system is disclosed in which a victim base station configures at least one resource for measuring cross-link interference (CLI) caused by wireless transmission from a remote aggressor base station. The victim base station determines the level of CLI based on the received signal strength value of the CLI reference signal from the remote aggressor base station. The received signal strength value may be a CLI channel state information reference signal received power value or a base station-specific CLI received signal strength indicator value.

Description

Technical Field

[0001] The present disclosure relates to a communication system.

Background Art

[0002] The present disclosure relates to a communication system. The present disclosure is particularly relevant, but not limited, to wireless communication systems and devices operating in accordance with 3rd Generation Partnership Project (3GPP (registered trademark)) standards or their equivalents or derivatives, including LTE-Advanced, next generation or 5G networks, future generations, and beyond. The present disclosure has a particular relevance, but not an exclusive relevance, to improved apparatus and methods for managing interference such as cross-link interference and remote interference in a time division duplex (TDD) communication band.

[0003] The recent developments of 3GPP specifications are called Long Term Evolution (LTE) of the Evolved Packet Core (EPC) network and the Evolved UMTS Terrestrial Radio Access Network (E-UTRAN), and are also generally referred to as "4G". Furthermore, the terms "5G" and new radio (NR) refer to the developing communication technologies that are expected to support various applications and services. Various details of the 5G network are described, for example, in the "NGMN 5G White Paper" V1.0 by the Next Generation Mobile Networks (NGMN) Alliance, and the document is available from https: / / www.ngmn.org / 5g-white-paper.html. 3GPP intends to support 5G with the so-called 3GPP Next Generation (NextGen) Radio Access Network (RAN) and 3GPP Next Gen core (NGC) networks.

[0004] Under 3GPP specifications, NodeB (or "eNB" in LTE and "gNB" in 5G) is a base station through which a communication device (User Equipment, i.e., "UE") connects to the core network and communicates with other communication devices or remote servers. For simplicity, this application uses the terms RAN node or base station to refer to such access nodes.

[0005] For simplicity, in this application, the terms mobile device, user device, or UE are used to refer to any communication device that can be connected to a core network via one or more base stations. Although this application may refer to mobile devices in the description, it will be understood that the technology described can be implemented on any communication device (mobile and / or generally fixed) that can be connected to a communication network to send and receive data, whether controlled by human input or by software instructions stored in memory.

[0006] Simultaneous transmission and reception between a base station and a user equipment (UE) is usually performed using different resources for the uplink and the downlink. The different resources may be different frequencies in the case of the Frequency Division Duplex (FDD) scheme, or may be time resources in the case of the Time Division Duplex (TDD) scheme. While an FDD network uses separate uplink and downlink frequency bands, a TDD network uses the same bandwidth and assigns different time slots to the uplink and the downlink. That is, in FDD, the resources in the frequency domain are divided between the downlink (DL) and the uplink (UL), whereas in TDD, the resources in the time domain are divided between DL and UL.

[0007] An appropriate duplexing scheme used in a certain scenario, although there is also an overlapping part, highly depends on the spectrum. When a lower frequency band is used for communication, usually the paired spectrum is allocated to UL and DL resources, so FDD is used. In contrast, in a higher frequency band, the use of unpaired spectrum, that is, TDD, is becoming increasingly popular. Therefore, TDD is widely used in commercial NR deployments. Considering that the carrier frequencies supported in 5G and in future communication generations (such as 6G and beyond) are particularly high compared to previous communication generations, improved technologies for efficiently using unpaired spectrum are becoming increasingly important and will continue to be important in the future.

[0008] In a TDD network, so-called cross-link interference such as cross-link interference between base stations (e.g., between gNBs) or between UEs (within a UE) may occur.

[0009] Cross-link interference between gNBs may occur when base stations transmit and receive in the same frequency band, and depending on the deployment scenario, it may take the form of, for example, adjacent channel cross-link interference, co-channel cross-link interference (or both).

[0010] The CLI between UEs includes, for example, the CLI (intra-cell CLI) that occurs between UEs in the same cell as a result of both DL and UL transmissions being able to occur in parallel. In this scenario, interference from adjacent sub-bands used for UL transmissions from other UEs in the same cell may be observed by a UE in the DL. Such interference can occur, for example, due to non-linear distortion or frequency errors (e.g., Doppler spread in DL reception). The interference is expected to manifest particularly in DL frequency resources close to UL resource elements (REs). This can be a serious problem that may reduce system efficiency if interference occurs in the reception of DL reference signals (e.g., the reception of channel state information RS (CSI-RS)).

[0011] For FD operation where sub-bands do not overlap, both intra-subband and inter-subband CLI may be particularly relevant.

[0012] Another form of CLI is referred to as remote interference. Remote interference occurs when radio waves from a transmitter (base station) propagate through the troposphere (which can be 300 - 400 km away) to a remote location due to atmospheric conditions, and these radio waves can interfere with local transmissions. 3GPP has introduced a so-called remote interference management reference signal (RIM-RS) to mitigate interference from the downlink signals of remote base stations in cases of atmospheric conditions suitable for the occurrence of tropospheric bending of radio waves.

[0013] The normal transmission range of a gNB (base station) is several kilometers. However, when tropospheric deflection of radio waves occurs, even if the victim gNB and the aggressor gNB are synchronized, the long transmission delay (up to 1.3 ms) of signals from the aggressor gNB propagating hundreds of kilometers is very likely to interfere with the UL reception of the victim gNB. This can potentially affect hundreds of base stations.

[0014] In the design of the frame structure in NR, a flexible Guard Period (GP) has already been considered to leave a large margin for avoiding remote interference. However, it is necessary to study a mechanism for specifying when and for how long a GP of sufficient length should be set.

[0015] 3GPP Technical Report (TR) 38.828 V16.1.0 discusses cross-link interference handling and Remote Interference Management (RIM) in NR. This document explains in Release 15 that synchronized TDD is expected to support the coexistence of different networks operating on adjacent carriers in the same band. As long as all networks apply uplink and downlink at the same opportunity, interference between adjacent carriers is mitigated.

[0016] Dynamic TDD represents an operating mode in which the network adapts the DL / UL subframe pattern according to traffic conditions. When different nodes in the same network apply DL and UL at different times, interference occurs between different UEs and different base stations. 3GPP has defined measurement values to mitigate cross-link interference (CLI) of the common channel in the same network. Dynamic TDD also causes interference between adjacent-channel networks. Different from the case of the common channel, the interference between adjacent-channel networks cannot be adjusted. Instead, since analog filtering is usually not feasible within the operating band, the interference is mitigated by the selectivity of the transmitter and receiver (adjacent channel leakage power ratio (ACLR) and adjacent channel selectivity (ACS)).

[0017] The recent Release 16 work item (3GPP RP-193190) discusses further details of cross-link interference handling and NR remote interference management. A new cell-specific reference signal for RIM (referred to as RIM-RS) has been introduced that implicitly indexes the cell ID using a triple of {time, frequency, sequence}. There are two types of RIM-RS, the first type is transmitted by the victim node, and the second type is transmitted by the aggressor (by correlation). An additional guard period is also provided for RIM.

[0018] Regarding CLI management between UEs, the currently proposed approach relies on the Sounding Reference Signal (SRS) for inter-UE CLI measurement. The so-called SRS Reference Signal Received Power (SRS-RSRP) is defined to enhance UE measurements for supporting CLI management. However, SRS-RSRP depends on the manufacturer's implementation, and it is not clear how to use it to mitigate interference via scheduling or what adjustments to make between two base stations.

[0019] Other 3GPP Release 16 work items (3GPP RP-213557) include research on the evolution of NR's duplex operation. This document is related to the sub-band non-overlapping duplexing scheme and potential enhancements of dynamic / flexible TDD. It also identifies possible schemes and evaluates their feasibility and performance. The purpose of this work item includes, in particular, considering intra-sub-band and inter-sub-band CLI in the case of sub-band non-overlapping full duplex, researching the handling of CLI between gNBs and UEs, and identifying solutions for managing them. It also includes researching the performance of the identified schemes as well as the impact on legacy operations where coexistence on the co-channel and adjacent channels is expected. Summary of the Invention Problems to be Solved by the Invention

[0020] However, an important issue not addressed in previous releases or the above-mentioned 3GPP work items is the CLI between gNBs. Specifically, there is still no agreement regarding CLI measurement and reporting, gNB adjustment mechanisms, and interference mitigation schemes.

[0021] Therefore, in order to enable efficient dynamic / flexible TDD in a communication network, there is a need for an extension to provide improved CLI handling between base stations and / or between UEs (of the same or different operators).

[0022] The present disclosure aims to provide an apparatus and a method that at least partially address the above needs and / or problems.

Means for Solving the Problems

[0023] According to one aspect, the present disclosure provides a method performed by a radio access network node, the method comprising identifying, for a plurality of other radio access network nodes, an aggressor node as a source of CLI within a cell of the radio access network node outside the serving area of the aggressor node, based on respective configuration information for determining Cross Link Interference (CLI).

[0024] According to one aspect, the present disclosure provides a method performed by a radio access network node, the method comprising transmitting at least one reference signal for measuring Cross Link Interference (CLI) caused outside the serving area of the radio access network node by a radio transmission from the radio access network node.

[0025] According to one aspect, the present disclosure provides a method performed by a radio access network node, the method comprising configuring at least one resource for measuring Cross Link Interference (CLI) caused outside the serving area of a transmitter by a radio transmission from the transmitter, and determining a level of the CLI based on a received signal strength value of a CLI reference signal received from the transmitter through the at least one resource.

[0026] According to one aspect, the present disclosure provides a method performed by a radio access network node, the method comprising detecting, based on a related reference signal, the occurrence of Cross Link Interference (CLI) caused outside the serving area of another radio access network node by a radio transmission from another radio access network node, and transmitting information indicating the occurrence of the CLI to a node in charge of CLI management.

[0027] According to one aspect, the present disclosure provides a method performed by a User Equipment (UE), the method comprising transmitting an uplink signal such that the arrival time of the uplink signal at a radio access network node coincides with the arrival time of a reference signal from another radio access network node for measuring Cross Link Interference (CLI).

[0028] According to one aspect, the present disclosure provides a radio access network node including means (e.g., a memory, a controller, and a transceiver) for identifying, based on respective configuration information for determining Cross Link Interference (CLI) regarding a plurality of other radio access network nodes, an aggressor node as a source of CLI within a cell of the radio access network node outside the serving area of the aggressor node.

[0029] According to one aspect, the present disclosure provides a radio access network node including means (e.g., a memory, a controller, and a transceiver) for transmitting at least one reference signal for measuring Cross Link Interference (CLI) caused outside the serving area of the radio access network node by a radio transmission from the radio access network node.

[0030] According to one aspect, the present disclosure provides a wireless access network node comprising means (e.g., memory, controller, and transceiver) for configuring at least one resource for measuring Cross Link Interference (CLI) caused outside the serving area of a transmitter by wireless transmission from the transmitter, and means for determining the level of CLI based on the received signal strength value of a CLI reference signal received from the transmitter through the at least one resource.

[0031] According to one aspect, the present disclosure provides a wireless access network node comprising means (e.g., memory, controller, and transceiver) for detecting, based on a related reference signal, the occurrence of Cross Link Interference (CLI) caused outside the serving area of another wireless access network node by wireless transmission from the other wireless access network node, and means for transmitting information indicating the occurrence of CLI to a node in charge of CLI management.

[0032] According to one aspect, the present disclosure provides a User Equipment (UE) comprising means (e.g., memory, controller, and transceiver) for transmitting an uplink signal such that the arrival time of the uplink signal at a wireless access network node coincides with the arrival time of a reference signal from another wireless access network node for measuring Cross Link Interference (CLI).

[0033] Aspects of the present disclosure extend to corresponding systems, apparatuses, and computer program products such as a computer-readable storage medium having computer-executable instructions operable to program a programmable processor to execute the methods described in the above aspects and possibilities or as claimed, and / or to program a computer appropriately adapted to provide an apparatus as claimed in any of the claims.

[0034] To facilitate the understanding of those skilled in the art, although the present disclosure is described in detail in the context of 3GPP systems (5G networks), the principles of the present disclosure can also be applied to other systems.

[0035] The present disclosure is defined by the claims appended hereto. Aspects of the present disclosure are as set forth in the independent claims. Some optional features are set forth in the dependent claims.

[0036] However, each feature disclosed and / or illustrated in this specification (which term includes the claims) may be incorporated into the present disclosure independently of (or in combination with) other disclosed and / or illustrated features. Without limitation, the features of claims dependent on a particular independent claim may be introduced into that independent claim in any combination or individually.

Advantages of the Invention

[0037] It is an object of the present disclosure to provide an apparatus and method that at least partially address the above needs and / or problems.

Brief Description of the Drawings

[0038] Next, exemplary embodiments of the present disclosure are described by way of example with reference to the accompanying drawings.

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[0039] Overview FIG. 1 schematically shows a (cellular or wireless) mobile telecommunications system 1 to which exemplary embodiments of the present disclosure may be applied.

[0040] In this system 1, a user of a mobile device 3 (UE) can communicate with each other and with other users via a base station 5 (and other access network nodes) and a core network 7 using a suitable 3GPP Radio Access Technology (RAT), e.g., Evolved Universal Terrestrial Radio Access (E-UTRA) and / or 5G RAT. It will be appreciated that several base stations 5 form a ((Radio) Access Network), i.e., (R)AN. As will be understood by those skilled in the art, for illustrative purposes, one mobile device 3 and two base stations 5A / 5B are shown in FIG. 1, but the system will typically include other base stations / (R)AN nodes and mobile devices (UEs) when implemented.

[0041] Each base station 5 controls one or more associated cells (either directly or via other nodes such as home base stations, relays, remote radio heads, distributed units, etc.). Base stations 5 that support next-generation / 5G protocols may be referred to as "gNBs". It will be understood that some base stations 5 may be configured to support both 4G and 5G communication protocols, and / or any other 3GPP or non-3GPP communication protocols.

[0042] The mobile device 3 and its serving base station 5 are connected via an appropriate radio interface (e.g., a so-called "NR" radio interface, "Uu" interface, etc.). Adjacent base stations 5 may be connected to each other via an appropriate inter-base station interface (e.g., a so-called "Xn" interface, "X2" interface, etc.). The base station 5 is also connected to the core network node via an appropriate interface (e.g., a so-called "NG-U" interface for the user plane, a so-called "NG-C" interface for the control plane, etc.).

[0043] The core network 7 (e.g., EPC in the case of LTE or NGC in the case of NR / 5G) typically includes logical nodes (or "functions") for subscriber management, mobility management, charging, security, and call / session management in order to support communication in the telecommunications system 1. For example, the core network 7 of a "next-generation" / 5G system includes user plane entities and control plane entities such as one or more Control Plane Functions (CPF) 10 and one or more User Plane Functions (UPF) 11. For example, the so-called Access and Mobility Management Function (AMF) 9 in 5G or the Mobility Management Entity (MME) in 4G is responsible for handling connection and mobility management tasks for the mobile device 3. The so-called Session Management Function (SMF) is responsible for handling communication sessions for the mobile device 3 such as session establishment, modification, and release. The core network 7 can typically also include, among others, an Authentication Server Function (AUSF), a Unified Data Management (UDM) entity, a Policy Control Function (PCF), and an Application Function (AF). It will be understood that nodes or functions may have different names in different systems. The core network 7 is connected to a Data Network (DN) such as the Internet or a similar Internet Protocol (IP)-based network (via the UPF 11). The core network 7 may be connected to an Operations and Maintenance (OAM) function (not shown).

[0044] In this system 1, cross-link interference (CLI) may occur in the form of remote interference. Such remote interference occurs when atmospheric conditions permit the propagation of radio waves from a transmitter (in this case, base station 5A) to a remote location (in this case, the location of base station 5B), and these radio waves can interfere with local transmissions. As shown in Figure 1, remote interference can occur over distances of just a few kilometers, well beyond the normal transmission range of a base station (gNB). In this scenario, the following definitions may be used: Aggressor gNB: The base station that transmits in the downlink and causes (or may cause) interference. Victim gNB: The base station that receives in the uplink and is affected by the interference. CLI between gNBs: Interference caused by downlink transmissions from an aggressor gNB to a victim gNB that performs uplink reception. Victim UE: The UE that performs an uplink transmission to a victim gNB and is affected by the CLI between gNBs.

[0045] Therefore, in the example shown in Figure 1, the first base station 5A is the aggressor of the CLI, and the second base station 5B and UE3 are the victims of the CLI.

[0046] To mitigate or reduce the impact of such remote interference, the nodes of system 1 are configured to perform one or more of the following procedures.

[0047] In the first procedure, the victim base station 5B identifies the aggressor base station 5A from among a plurality of potential aggressors based on configuration information regarding CLI for each of the potential aggressors.

[0048] In the second procedure, the aggressor base station 5A transmits at least one reference signal for measuring CLI caused outside the serving area of the aggressor base station 5A by wireless transmissions from the aggressor base station 5A.

[0049] In the third procedure, the base stations 5A and 5B configure at least one resource for measuring CLIs outside the serving area of the transmitter of the aggressor base station 5A. The level of the CLI is determined based on the received signal strength value of the CLI reference signal from the transmitter of the aggressor base station 5A through at least one resource.

[0050] In the fourth procedure, the victim base station 5B detects the occurrence of CLIs generated outside the serving area (cell) of the aggressor base station 5A based on the relevant reference signals. The victim base station 5B transmits information indicating the occurrence of the CLIs to a node (which may be another base station or an OAM function) responsible for CLI management.

[0051] In the fifth procedure, the UE3 and the aggressor base station 5A are configured to transmit such that the arrival time of the uplink signal from the UE3 at the victim base station 5B coincides with the arrival time of the CLI reference signal from the aggressor base station 5A.

[0052] Advantageously, using one or more of the following procedures, the nodes of this system 1 can mitigate or reduce harmful remote interference.

[0053] User Equipment (UE) Figure 2 is a block diagram showing the main components of the mobile device (UE) 3 shown in Figure 1. As shown, UE 3 includes a transceiver circuit 31 operable to transmit signals to and receive signals from at least one connected node via one or more antennas 33. Although not necessarily shown in Figure 2, UE 3 of course has all the normal functions of a conventional mobile device (such as user interface 35), which may be provided by any one of hardware, software, and firmware or any combination thereof as required. The controller 37 controls the operation of UE 3 according to software stored in the memory 39. The software may be pre-installed in the memory 39 and / or downloaded, for example, via the telecommunications network 1 or from a Removable Data storage Device (RMD). The software includes, among other things, an operating system 41, a communication control module 43, and an interference (e.g., CLI) management module 45.

[0054] The communication control module 43 is responsible for processing (generating / sending / receiving) signaling messages and uplink / downlink data packets between UE 3 and other nodes including the (R)AN node 5 and core network nodes. The signaling may include control signaling related to CLI management, such as the configuration of resources for CLI reference signals and measurements. The communication control module 43 is also responsible for determining and applying an appropriate TDD and / or FDD configuration.

[0055] The interference / CLI management module 45 is responsible for CLI management, such as receiving and applying relevant reference signal configurations (via the communication control module 43).

[0056] Access network node (base station) Figure 3 is a block diagram showing the main components of the base station 5 (or a similar access network node) shown in Figure 1. As shown, the base station 5 is operable to transmit signals to at least one connected UE 3 and receive signals from at least one connected UE via one or more antennas 53, and to transmit signals to (directly or indirectly) other network nodes and receive signals from other network nodes via a network interface 55, including a transceiver circuit 51. The network interface 55 typically includes appropriate inter-base station interfaces (such as the X2 / Xn interface) and appropriate base station-core network interfaces (such as the S1 / N1 / N2 / N3 interface). A controller 57 controls the operation of the base station 5 according to software stored in a memory 59. The software may be pre-installed in the memory 59 and / or may be downloaded, for example, via the telecommunications network 1 or from a Removable Data storage Device (RMD). The software includes, among other things, an operating system 61, a communication control module 63, and an interference (e.g., CLI) management module 65.

[0057] The communication control module 63 is responsible for handling (generating / transmitting / receiving) signaling between the base station 5 and other nodes such as the UE 3 and core network nodes. The signaling may include control signaling related to CLI management, such as CLI reference signals and configuration of resources for measurements. The communication control module 63 is also responsible for controlling and applying appropriate TDD and / or FDD configurations.

[0058] The interference / CLI management module 65 is responsible for CLI management in the radio access network portion to which the access network node belongs and for exchanging CLI-related assistance information with other access network nodes (directly or via the core network 7).

[0059] Core Network Function FIG. 4 is a block diagram showing the main components of a general core network function, such as the CPF10 or UPF11 shown in FIG. 1. As shown, the core network function includes a transceiver circuit 71 operable to transmit signals to and receive signals from other nodes (including UE3, base station 5, and other core network nodes) via network interface 75. A controller 77 controls the operation of the core network function according to software stored in a memory 79. The software may be pre-installed in the memory 79 and / or downloaded, for example, via communication network 1 or from a Removable Data storage Device (RMD). The software includes, among other things, an operating system 81, a communication control module 83, and an interference (e.g., CLI) management module 85.

[0060] The communication control module 83 is responsible for processing (generating / sending / receiving) signaling between the core network function and other nodes such as UE3, base station 5, and other core network nodes. The signaling may include control signaling related to CLI management, such as CLI reference signals and configuration of resources for measurements.

[0061] The interference / CLI management module 85 is responsible for assisting in CLI management in the radio access network portion served by the core network node.

[0062] Detailed Description In the present disclosure, the following definitions are used. Aggressor gNB: A base station (gNB) that transmits in DL Victim gNB: A base station (gNB) that receives in UL gNB - to - gNB CLI: Interference caused by DL transmission from an aggressor gNB to a victim gNB that receives UL Victim UE: A UE that performs UL transmission to the victim gNB and is affected by CLI between gNBs

[0063] The above nodes and their relationships are schematically shown in FIG. 8.

[0064] Method for identifying the aggressor FIG. 9 schematically shows an exemplary scenario in which an aggressor base station 5A (denoted by "gNB 5A") generates CLI to a victim base station 5B (denoted by "gNB 5B"). Specifically, the transmitter (Tx) beam #1 of base station 5A causes interference to the receiver (Rx) beam #1 of base station 5B.

[0065] In this scenario, the victim base station 5B needs to identify the interference source (in this example, base station 5A) in order to mitigate the interference from that specific aggressor. In the case of beamforming, as shown in FIG. 9, not only the aggressor node, e.g., gNB 5A, but also the aggressor beam, e.g., the Tx beam #1 of gNB 5A, should be identified. Once the aggressor base station / beam is identified, for example, during the period when the aggressor base station 5A transmits in the downlink, more specifically, during one or more specific symbols / slots corresponding to the period when the signal transmitted by the aggressor base station 5A arrives at the cell of the victim base station 5B (with a delay depending on the distance between the two base stations 5A and 5B), the interference can be mitigated by not scheduling UE3 covered by the aggressing beam.

[0066] In the case of remote interference, since the aggressor and victim nodes may be located at a relatively large distance from each other, they are not considered adjacent for mobility, load balancing, dual connectivity, and / or similar normal network operations.

[0067] In this example, the base stations 5 have an inter-base station interface (e.g., Xn interface, and / or the like) between them. Advantageously, the base stations 5A and 5B may be configured to exchange information suitable for assisting other base stations in the mitigation of CLI through the Xn interface (or other inter-base station interfaces). Specifically, the base station 5 (at least the aggressor 5A) may be configured to transmit configuration information related to CLI management (including TDD configuration, beam configuration, and reference signal configuration, and / or the like) to other base stations 5. The base stations 5 can exchange this information once (e.g., upon establishment or connection between them) or periodically (on demand, periodically, or in response to changes in their configuration) to support their mutual dynamic TDD operation.

[0068] It will be appreciated that if a direct inter-base station interface (e.g., Xn interface) is not available for information exchange, RRC containers may be used to exchange relevant information between two base stations via the Ng interface and / or the like. For example, the aggressor base station 5A can transmit this information to the core network 7 (via the Ng interface using one or more appropriate RRC containers), and the core network 7 can transfer the information (at least one RRC container) to one or more other base stations 5B, where the other base stations 5B can be one or more victims of CLI caused by the transmission from the base station 5A.

[0069] FIG. 10 schematically shows an exemplary procedure for identifying an aggressor base station (indicated by "gNB 5A") by a victim base station (indicated by "gNB 5B") using the approach described above. In this case, the base stations 5 exchange appropriate assistance information through the inter-base station interface (e.g., Xn and / or the like) between them.

[0070] In this example, there are five base stations 5, among which gNB 5B is the victim base station and gNB 5A is the aggressor. The Rx beam #1 of gNB 5B receives the CLI from gNB 5A (its beam).

[0071] In this approach, the victim base station 5B identifies the aggressor 5A based on the applicable TDD configuration, beam configuration, and gNB location information exchanged via the base station - to - base station interface (or via the core network 7). In other words, at least some of the base stations shown in FIG. 10 are configured to support such information exchange to assist in CLI management.

[0072] The procedure includes the following steps.

[0073] Step 1: The victim base station 5B exchanges TDD configuration information with the surrounding base stations 5, and based on such information, knows which at least one base station 5 performs DL transmission when performing UL reception in one or more specific symbols / slots. Accordingly, a list of potential aggressors is created.

[0074] The information to be exchanged can include, for example, common or dedicated uplink / downlink configurations (which can be included in the so - called tdd - UL - DL - ConfigurationCommon and tdd - UL - DL - ConfigurationDedicated information elements respectively), downlink control information (DCI) formats (e.g., DCI format 2_0), and any additional parameters related to sub - band non - overlapping full - duplex operation such as one or more symbols / slots / frequency bands used for UL and / or DL.

[0075] The exact type of information to be exchanged and the frequency of information exchange may depend on the performance of the interface used between the base stations 5. It will be understood that a subset of the above - mentioned parameters may be exchanged.

[0076] In this example, after step 1, the victim base station 5B may narrow down potential aggressors to an initial set (or list) of potential aggressor nodes including base stations 5A, 5C, 5D, and 5E that have exchanged relevant TDD (or CLI) related information with the victim base station 5B, based on the exchanged information.

[0077] Step 2: The victim base station 5B may further derive potential aggressors based on information related to its own position and Rx beam (e.g., beam direction, beam width, etc.) based on the positions of other base stations, and reduce the size of the initial list. In this example, after step 2, the victim base station 5B may narrow down the initial set (list) of potential aggressor nodes to base stations 5A and 5C (i.e., remove base stations 5D and 5E from the list of potential aggressors).

[0078] Step 3: The victim base station 5B and the surrounding base stations 5 exchange transmission beam configuration information (e.g., configuration of related reference signals such as beam direction, beam width, NZP-CSI-RS, SSB, etc.). It will be understood that this information may be exchanged as part of the information exchanged in step 2. Based on this information, the victim base station 5B may be able to identify one or more potential aggressing beams. In this example, the victim base station 5B may be able to narrow down the potential aggressor to base station 5A and a specific beam of that base station 5A.

[0079] (Optional) Step 4: Each base station 5 may be configured to share its aggressor list and / or aggressor beam list with the central controller. The central controller may be, for example, an Operations Administration and Maintenance (OAM) function, or one of the base stations, depending on whether a centralized or distributed CLI management mechanism is being used. Alternatively, the victim base station 5B may indicate to the central controller that it is experiencing CLI, and the central controller may execute Steps 1 - 3 to derive a list of aggressor nodes and / or beams (at least one aggressor node and / or beam) for the victim base station 5B and send this list to the victim base station 5B.

[0080] It will be understood that there may be one or more aggressors (and / or one or more beams or cells may receive CLI), in which case the procedure may be applied separately to each aggressor or beam / cell. Alternatively, if appropriate, a single procedure may identify one or more aggressors or beams.

[0081] It will be understood that the process may stop at any step between Steps 1 - 3 and provide a different level or granularity of aggressor identification. Thus, the following alternatives are envisioned. Alternative 1: By executing only Step 1, an aggressor gNB list {5A, 5C, 5D, 5E} becomes available. Alternative 2: By executing Steps 1 and 2, a more specific, reduced - size aggressor gNB list {5A, 5C} becomes available. Alternative 3: By executing Steps 1, 2, and 3, an even more reduced - size (or, in this example, of a specific aggressor) aggressor gNB list {gNB 5A} becomes available.

[0082] Advantageously, the victim base station 5B can identify the aggressor node (at least a list of potential aggressor nodes) based on the available information and perform appropriate actions to mitigate the CLI caused by one or more aggressor nodes.

[0083] To ensure effective CLI management, it may be necessary to update the aggressor gNB / beam list. This may be updated on demand (e.g., when the CLI is detected again), exchanged when one TDD / beam configuration of the base station is changed, or updated periodically (e.g., based on a related timer), depending on the performance of the Xn interface.

[0084] Also, it will be appreciated that when the aggressor base station 5A is identified, the aggressor base station 5A may indicate its transmission power to the victim base station 5B. Alternatively, the transmission power information may be provided by each potential aggressor node and this information may be used in any of steps 1 to 3.

[0085] The transmission power information may be used by the victim base station 5B to determine whether the transmission of the (potential) aggressor base station interferes with the victim base station 5B.

[0086] Figures 11 and 12 schematically show exemplary other procedures for identifying an aggressor base station without having (or using) an inter-base station interface between base stations. In this case, a beam sweep (Figure 11) or a nulling beam sweep (Figure 12) is used to identify the aggressor.

[0087] More specifically, one or more aggressor nodes may be identified based on the relevant TDD configuration and location information (exchanged via the Xn interface) without exchanging (or having the ability to exchange) beam information between base stations 5.

[0088] In this scenario, steps 1 and 2 may be the same as those described above with reference to FIG. 10.

[0089] However, in step 3, each potential aggressor base station 5 performs a beam sweep or nulling beam sweep operation to assist the victim base station 5B in measuring the CLI level (or change in CLI level) used to identify which beam causes a CLI for that particular victim base station 5B. The measured CLI level (or change in CLI level) may be reported to the associated potential aggressor node. Based on this report, the potential aggressor node (gNB) can determine whether it is an aggressor towards other nodes and identify which Tx beam is the aggressor beam (or aggressor beams).

[0090] In the case of a beam sweep, the (aggressor) base station 5A turns on its beams one by one (in other words, schedules downlink communication via different beams in sequence), and the victim base station 5B reports the measured CLI level to the base station 5A. Based on this report, the base station 5A can identify the beam that causes a high level of CLI (e.g., CLI exceeding the associated threshold).

[0091] In the case of a nulling beam sweep, the (aggressor) base station 5A turns off its beams one by one (in other words, does not schedule downlink communication via different beams in sequence), and the victim base station 5B reports the change in the measured CLI level to the base station 5A. In this case, the aggressing beam causes the largest change in the CLI level. Based on this report, the base station 5A can identify the aggressor beam.

[0092] It will be appreciated that beam sweeping may be performed in an active or passive manner. When active beam sweeping is used, aggressor base station 5A may actively configure an appropriate reference signal for beam sweeping (e.g., the CSI-RS / SSB reference signal described later). In this case, the beam does not necessarily have to be the beam used for actual data transmission within the cell of base station 5A. This approach can beneficially reduce the interruptions caused by the transmission of base station 5A due to the beam sweeping operation. Furthermore, it can be used to identify additional potential aggressing beams (which will cause CLI to other base stations in the future). For each Tx beam, victim base station 5B reports its respective measurement results to base station 5A.

[0093] When passive beam sweeping is used, aggressor base station 5A performs beam sweeping only for the beams currently in use (or expected to be used shortly). For the currently used beam, even the demodulation reference signal (DMRS) or even data may be used for CLI measurement by victim base station 5B. For other beams, CSI-RS / SSB may be used. For each Tx beam, victim base station 5B reports its respective measurement results to base station 5A.

[0094] The method of nulling beam sweeping may be applied only to the beam currently used for data transmission.

[0095] What to measure? It will be appreciated that any of the following approaches may be used for CLI management. -Alt1: Measure reference signals, e.g., Channel State Information-Reference Signal (CSI-RS), Synchronization Signal Block (SSB), Demodulation Reference Signal (DMRS): In this case, the configuration of the applied reference signals needs to be exchanged between base stations; -Alt2: Measure data transmission from the aggressor; and -Alt3: Perform blind measurements.

[0096] To support CLI-specific measurements, the following measurement functions are proposed for base station 5: -(For Alt1) Measurement of CLI CSI-RS RSRP; -(For Alt2) Measurement of gNB CLI-RSSI.

[0097] In the case of Alt1, the CLI CSI reference signal received power (CLI CSI-RSRP) is defined as the linear average of the power contributions ([in W]) of the resource elements of one or more antenna ports that transmit the CSI reference signal indicated for CLI RSRP measurement within the measured frequency bandwidth considered in the indicated CSI-RS opportunity.

[0098] Regarding the determination of CSI CSI-RSRP, it is assumed that it is indicated which antenna port the CSI reference signal is transmitted from, and it is expected that base station 5 can measure one or more CLI CSI-RS resources outside the active downlink bandwidth part.

[0099] Specifically, the reference point of CLI CSI-RSRP is -For type 1-C base stations: Rx antenna connector, -For type 1-O or 2-O base stations: Based on the combined signal from the antenna elements corresponding to a specific receiver branch - For Type 1-H base stations: The Rx transceiver array boundary connector.

[0100] In the above list, the Type 1-C, Type 1-O, Type 2-O, and Type 1-H base stations correspond to their respective definitions described in 3GPP TS 38.104.

[0101] For frequency ranges 1 and 2, when receiver diversity is used by base station 5, the reported CLI CSI-RSRP value shall not be lower than the corresponding CLI CSI-RSRP of any of the individual receiver branches.

[0102] It should be noted that Alt1 can be extended to other reference signals such as SSB, DMRS, etc. depending on the selection of the base station.

[0103] Now, regarding Alt2, the gNB-specific CLI Received Signal Strength Indicator (CLI-RSSI) is defined as the linear average of the total received power (in [W]) observed only in the indicated OFDM symbols of the indicated one or more measurement time resources, and is observed over the indicated measurement bandwidth from all sources including the co-channel serving cell and non-serving cells, adjacent channel interference, self-interference, thermal noise, etc.

[0104] Base station 5 is expected to be able to measure one or more resources outside the active downlink bandwidth part.

[0105] The reference point of the gNB CLI RSSI is - For Type 1-C base stations: The Rx antenna connector, - For Type 1-O or 2-O base stations: Based on the combined signal from the antenna elements corresponding to a specific receiver branch, - For Type 1-H base stations: The Rx transceiver array boundary connector.

[0106] For frequency ranges 1 and 2, when receiver diversity is being used by base station 5, the reported gNB CLI RSSI value must not be lower than the gNB CLI RSSI corresponding to any of the individual receiver branches.

[0107] When to measure? Regarding the question of when to trigger the CLI measurement, two main cases and some related solutions can be identified.

[0108] Case 1: When the so-called complete Xn interface is used between base stations, both the victim base station 5B and the aggressor base station 5A know when and where the CLI occurs based on the TDD-related configuration information exchanged between them. In this case, the following solutions can be used. Solution 1: Since it is possible that the CLI level is not high enough to affect UL transmission, when a gNB-gNB CLI occurs, UE UL transmission is permitted. The CLI measurement may be performed during UL transmission from the first symbol / slot when the gNB CLI occurred. Solution 2: When gNB-gNB CLI measurement is performed, UE UL transmission is not permitted, and the victim base station 5B may need to perform the CLI measurement before UL transmission.

[0109] Case 2: When an incomplete Xn interface is used between base stations, the victim base station 5B and the aggressor base station 5A may not have sufficient knowledge of when and where the CLI occurs because they may not be exchanging all (or any) of the TDD-related configuration information. Solution: In this case, the CLI measurement may be performed when the performance of UL transmission is affected, which can be indicated, for example, by a higher value of the related Block Error Rate (BLER) or a lower value of the related Signal-To-Interference-Plus-Noise Ratio (SINR).

[0110] (For either Case 1 or Case 2) Other solutions allow the victim base station 5B to periodically measure the CLI without a related trigger. Alternatively, all solutions may be flexibly combined.

[0111] For both cases, the parameter T delta (T Δ ) may be defined and configured to indicate the time difference between the time of CLI measurement and the time when relaxation of the CLI is expected to be applied. This parameter may be communicated to the UE3 so that the UE3 knows when the CLI can be relaxed.

[0112] FIG. 13 schematically shows an exemplary method of defining T based on a value (T0) representing the time when CLI measurement starts and another value (T1) representing the time when application of CLI relaxation is expected. Δ

[0113] Note that the operation of the above Xn interface may also be applicable to the Ng interface when the Xn interface is not available.

[0114] Measurement method FIG. 14 schematically shows an exemplary approach for performing measurements for CLI relaxation in the system of FIG. 1. In this case, the following definitions apply (in addition to those given with reference to FIG. 8). Aggressor gNB: The base station (gNB) that configures and transmits non-zero power (NZP) reference signals such as CSI-RS, DMRS, SSB, etc. to indicate the gNB-gNB CLI level Victim gNB: The base station (gNB) that configures one or more time-frequency resources as CLI measurement reference signals / resources and measures the signal strength received on those resources, e.g., by receiving CSI-RS from the Aggressor gNB gNB-gNB CLI: The signal strength of NZP RS from the aggressor gNB indicating the interference level of the gNB-gNB CLI. Victim UE: A UE composed of a set of one or more time-frequency resources for CLI measurement by the victim gNB

[0115] For the details of the problems of the CLI measurement method, refer to FIGS. 15 to 17 for explanation.

[0116] FIG. 15 shows a first alternative. In this case, a new RS type, for example, Zero Power (ZP) SRS, is configured for the victim UE 3. The victim base station 5B measures the CLI in one or more ZP SRS resources. It will be understood that the ZP SRS can be configured according to the same (or identical) configuration rules as the SRS for one or more resources / resource sets for one or more beams / gNBs. In the example shown in FIG. 15, the ZP SRS (for CLI) is configured for one or more symbols following the normal SRS symbol. The number of ZP SRS may be up to n_max OFDM symbols, where n_max is an integer having a value of 12 or less.

[0117] The comb coefficient of the ZP SRS may be selected from the set {1, 2, 4, 8, 16} depending on the maximum number of aggressors (e.g., comb coefficient 1 in FIG. 15). Thus, the number of measurable aggressors is given by n_max * comb_factor * n_code, where n_code is the number of orthogonal codes in the code domain.

[0118] FIG. 16 shows a second alternative. In this case, an appropriate (CLI-specific) puncturing pattern is configured for the victim UE 3. The UL data and / or SRS may be punctured for the time and frequency resources shown in the relevant pattern configuration. It will be understood that when the data is punctured, the actual coding rate of the UL increases.

[0119] Figure 17 shows the third alternative. In this case, a ZP CLI management RS is configured for the victim UE3. Compared with the second alternative described above, the actual coding rate and the sounding performance of the UL channel remain unchanged.

[0120] It will be understood that there may be cases where multiple resources and resource sets are configured for each base station 5. Each resource may correspond to each of its respective aggressive beams, for example, CLI IM RS#1 for Tx beam #1 of aggressor base station 5A, CLI IM RS#2 for Tx beam #2 of (the same) aggressor base station 5A, and CLI IM RS#3 for Tx beam 3. Each resource set may correspond to a specific aggressor base station 5A. For example, CLI IM RS#1, #2, and #3 may belong to the same resource set corresponding to one aggressor base station 5A.

[0121] In a fourth alternative, ZP CSI-RS resources may be configured. These resources may be configured for the UE3 served by the victim base station 5B for rate matching / puncturing when a CSI-RS type of resource configuration is used by the CLI.

[0122] Compared with the configuration of ZP CSI-RS resources for DL rate matching / puncturing currently supported in NR, in this system 1, the resources may also be used for UL rate matching / puncturing. Similar to the DCI-based indication for the Physical Downlink Shared Channel (PDSCH), the DCI for the Physical Uplink Shared Channel (PUSCH) may also be adapted to indicate which ZP CSI-RS resources to activate.

[0123] Figure 18 schematically shows potential timing problems in the case of CLI, that is, the problem of transmission deviation by the aggressor and the victim (UE in this case).

[0124] Thus, the arrival time of the UL signal from the victim UE3 and the arrival time of the interference signal from the aggressor base station 5A may not match due to the relationship of the distance between the two. The UL signal from the victim UE3 arrives at time T0, and the interference signal from the aggressor arrives at time T1 (at the victim base station 5B).

[0125] Timing difference T Δ1 = T1 - T0 depends on the propagation delay and may be greater than the period of the applicable cyclic prefix (CP), so the CLI measurement may be affected. In Figure 18, the following definitions are applied. T0: Arrival timing of the UL signal from the victim UE3 T1: Arrival timing of the interference signal from the aggressor node (gNB 5A)

[0126] In this example, the DL transmission of the entire network 1 is synchronized. That is, T_DL indicates the DL timing of both base station 5A and base station 5B. Since T_DL may also include the UL / DL or Tx / Rx transition time, it is assumed to be equal to or (substantially) close to T0.

[0127] UE3 is composed of relevant Timing Advance (TA) values [in ms] given by the formula TA = N TA + N TA,offset Therefore, as shown in Figure 19, UE3 transmits TA ms earlier than T0.

[0128] To support efficient CLI management, the following solutions are proposed. Alt1: The aggressor base station 5A is at T rather than T0 Δ2=T0 - T3 [ms] Transmit its own reference signal earlier (where T0 represents the corresponding DL timing of the victim base station 5B). In the synchronous network, T_DL is applied to both the aggressor base station 5A and the victim base station 5B. Since T_DL may also include the UL / DL or Tx / Rx transition time, it is assumed to be (substantially) equal to or close to T0.

[0129] An example of this solution is shown in Figure 20.

[0130] In this case, T Δ2 is less than or equal to the value obtained by dividing the distance between the aggressor base station 5A and the victim base station 5B by c (the speed of light, or the speed of radio waves in this case). This makes the arrival times of the UL signal from the victim UE and the interference signal from the aggressor base station 5A coincide. In this context, coincidence means that T Δ1 =T1 - T0 is less than the period of the CP used in the cell of the victim base station 5B.

[0131] There is no need to change the operation of UE3. Therefore, Alt1 may depend on the implementation of the base station (gNB).

[0132] Alt2: In this case, since the aggressor base station 5A may affect its own DL transmission timing, it does not transmit its own reference signal earlier. However, the victim UE3 is configured to delay its transmission by an amount that aligns the UL transmission of the UE with the downlink signal from the aggressor base station 5A (shown by T Δ3 ).

[0133] An example of this solution is shown in Figure 21, where T_DL = T3 represents the DL timing of both the aggressor base station 5A and the victim base station 5B (assuming a synchronous network).

[0134] T Δ3 is such that the arrival times of the UL signal from the victim UE3 and the interference signal from the aggressor base station 5A coincide (i.e., TΔ1 =(T1 - T0) is configured to be smaller than the period of the CP used in the cell of the victim base station 5B. T Δ3 It should be understood that may be absorbed into the Timing Advance (TA) value of the UE. In this case, a negative TA value may be required.

[0135] In Alt2, since the UL transmission of the victim UE 3 is delayed, the UL / DL of the UE itself may become inconsistent. This problem may be addressed by introducing an additional GP (between the UL resource and the DL resource).

[0136] Measurement report Referring to FIGS. 22 and 23, the following is a discussion of some exemplary ways in which measurement results can be reported to perform appropriate CLI management actions. Alt1 (FIG. 22): In the case of centralized CLI management, report the measurement results to a centralized controller (e.g., OAM). Alt2 (FIG. 23): In the case of distributed CLI management, report the measurement results to the aggressor node (e.g., via the Xn interface).

[0137] The reporting may be performed periodically, semi - persistently, and / or aperiodically (on - demand).

[0138] In the cases of semi - persistent and on - demand aperiodic reporting, the reporting may be performed (in response) based on a request from the OAM or the aggressor. Also, the reporting may be initiated by the victim base station 5B when the detected / measured interference exceeds a relevant threshold. The threshold may be predefined or may be configured based on the signal power received in the UL.

[0139] CLI - RS resource configuration The following is an explanation of some exemplary ways to configure the CLI - specific reference signal (CLI - RS) and an explanation of when to transmit the CLI - RS.

[0140] The CLI-RS resource may have a persistent / semi-persistent period or may be an aperiodic CLI-RS resource.

[0141] In the case of a persistently allocated resource, cell-specific legacy RSs (such as CSI-RS and SSB) may be used for measurement.

[0142] In the case of semi-persistent / aperiodic resources, the base station 5 may exchange information regarding the time opportunities for their RS transmissions. This exchange may be triggered, for example, when a TDD collision is identified by one of the base stations 5.

[0143] In one alternative, the victim base station 5B may request the aggressor base station 5A to transmit CLI-RS, and the aggressor base station 5A may indicate applicable resource reservations and transmit CLI-RS accordingly.

[0144] In another alternative, the aggressor base station 5A transmits its CLI-RS and provides information regarding the used CLI-RS resource configuration to the victim base station 5B (by itself, i.e., without a request from the victim base station 5B).

[0145] Regarding the issue of when to transmit the CLI-RS, the time resources for the CLI-RS may be defined at the slot / symbol level. The slot / symbol type used for CLI-RS transmission may be selected as follows: 1) The victim base station 5B can measure and receive the RS. This means that during the victim UL slot / symbol or when the victim base station 5B is not performing transmission, the CLI-RS transmission should be carried out. 2) The CLI-RS transmission is carried out during the DL slot or when there is no transmission so that the DL RS does not interfere with the UL reception.

[0146] According to the above point 2, the RS should be transmitted as follows: Option 1: Transmit CSI-RS in one or more DL slots / symbols of the aggressor base station that overlap with one or more UL slots / symbols of the victim base station (this means that the CLI-RS is transmitted only in the conflicting slots). Option 2: Transmit CSI-RS in one or more UL slots / symbols of the victim base station that overlap with any flexible slot of the aggressor base station. Option 3: Transmit CSI-RS in DL slots / symbols of the aggressor base station that overlap with the flexible slot of the victim base station. Option 4: Transmit CSI-RS in a flexible slot that overlaps in both the victim base station and the aggressor base station.

[0147] To implement Options 2 to 4, the base stations may need to share information about flexible time opportunities with each other.

[0148] The type of CLI-RS resources used may also depend on the respective slot / symbol types of the aggressor base station and the victim base station. For example, if the UL slot / symbol of the victim base station is used for CLI-RS transmission, an SRS type of resource configuration may be used. Otherwise, a CSI-RS type of resource configuration may be used.

[0149] It will be understood that additional restrictions may be applied to CLI-RS transmission so that the CLI-RS is transmitted for at least a certain period before the start of the conflicting slot. Such additional restrictions regarding CLI-RS timing may be implemented using fixed values (defined, for example, in the relevant 3GPP specifications), or values determined by the victim base station and indicated to the aggressor base station.

[0150] When CSI-RS is transmitted to avoid contention in DL+UL slots, CLI-RS can be transmitted only on frequency resources and beams where contention is expected to occur (i.e., on the DL of the aggressor base station and the UL of the victim base station). It will be understood that this information (i.e., frequency resource / beam information) may need to be exchanged between base stations.

[0151] Modifications and alternatives Detailed embodiments have been described above. As will be understood by those skilled in the art, many modifications and alternatives may be applied to the above embodiments while enjoying the benefits of the disclosure embodied therein.

[0152] For example, for clarity, terms specific to cellular communication generations (such as 2G, 3G, 4G, 5G, 6G, etc.) may be used to refer to specific communication entities, but it will be understood that the technical features described for a given entity are not limited to devices of that specific communication generation. The technical features may be implemented in any functionally equivalent communication entity, regardless of any differences in the terms used to refer to them.

[0153] When sub-band full-duplex (SBFD) operation is used, it should be understood that the CLI-RS or puncturing pattern may be configured within one or more sub-bands. The CLI-RS or puncturing pattern may be configured in a periodic, semi-persistent, or dynamic manner. In the case of periodic and semi-persistent configurations, radio resource control (RRC) signaling (e.g., one or more appropriately formatted information elements) may be used for the configuration of the CLI-RS or puncturing pattern, and medium access control (MAC) signaling (e.g., MAC control elements) may be used for the activation / deactivation of the CLI-RS or puncturing pattern. In the case of dynamic configuration, appropriately formatted downlink control information (DCI) may be used for configuration / activation / deactivation, or RRC may be used for configuration and DCI may be used for activation / deactivation.

[0154] The type of CLI-RS or puncturing resources may depend on the CLI-RS resource configuration type. For example, if the CLI-RS resource configuration is of the SRS type, the first alternative means (ZP SRS, Figure 15) described above may be used, and if the CLI-RS resource configuration is of the CSI-RS type, the fourth alternative means (ZP CSI-RS resources) described above may be used.

[0155] Multiple CLI measurement RS resources / resource sets may be configured at different times and frequency resources for a single aggressor base station so as to be able to measure multiple Tx beams simultaneously. One or more identical CLI measurement RS resources / resource sets may be configured for multiple beams as long as the sequences of one or more RSs associated with these beams are orthogonal to each other.

[0156] Regarding one or more frame structures that may be used in the above communication system, it will be understood that the base station and the UE communicate with each other using resources organized into frames of length 10 ms in the time domain. Each frame includes 10 equal-sized subframes of length 1 ms. Each subframe is divided into one or more slots containing 14 orthogonal frequency-division multiplexing (OFDM) symbols of the same length. For example, each column in FIGS. 15 to 17 may represent one OFDM symbol, and in this case, 14 consecutive symbols in FIGS. 15 to 17 may represent one subframe.

[0157] However, the communication system supports multiple different numerologies (subcarrier spacing (SCS), slot length, and thus OFDM symbol length). Specifically, each numerology is identified by the parameter μ, and μ = 0 represents 15 kHz (corresponding to LTE SCS). Currently, the SCS for other values of μ can be derived by effectively scaling up from μ = 0 by a power of 2 (i.e., SCS = 15x2 μ kHz). The relationship between the parameter μ and the SCS (Δf) is shown in Table 1. [Table 1]

[0158] In the above description, the UE, access network node (base station), and core network functions have been described as having a number of individual functional components or modules for ease of understanding. These modules may be provided in this way for a particular application, for example, when an existing system is modified to implement the present disclosure, but in other applications, for example, in a system designed from the outset with the features of the present invention in mind, these modules may be incorporated into the overall operating system or code, and thus may not be distinguishable as individual entities.

[0159] In the above embodiment examples, a number of software modules have been described. As will be understood by those skilled in the art, software modules may be supplied to the UE, access network node (base station), or core network functions, in compiled or uncompiled form, as a signal via a computer network, or on a recording medium. Further, the functions performed by some or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred as it facilitates updating the UE, access network node (base station), or core network functions to update their functions.

[0160] Each controller may include a processing circuit in any suitable form, including (but not limited to), for example, one or more hardware-implemented computer processors, microprocessors, central processing units (CPUs), arithmetic logic units (ALUs), input / output (IO) circuits, internal memory / cache (program and / or data), processing registers, communication buses (e.g., control bus, data bus, and / or address bus), direct memory access (DMA) functions, hardware- or software-implemented counters, pointers, and / or timers, etc. Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

[0161] The base station may include a "distributed" base station having a central unit "CU" and one or more separate distributed units (DUs). For example, a gNB may be split into a CU and one or more DUs connected by a so-called F1 interface. This enables the use of a "split" architecture, whereby typically a "higher" CU layer (not necessarily or exclusively, e.g., PDCP) and typically a "lower" DU layer (not necessarily or exclusively, e.g., RLC / MAC / PHY) are implemented separately. Thus, for example, while the DU function of the lower layer is locally maintained in each gNB, the CU function of the higher layer of multiple gNBs may be implemented centrally (e.g., by a single processing unit or in a cloud-based or virtualized system).

[0162] User Equipment (i.e., "UE", "mobile station", "mobile device", or "wireless device") in the present disclosure is an entity connected to a network via a wireless interface.

[0163] Note that the present disclosure is not limited to dedicated communication devices and can be applied to any device having a communication function as described in the following paragraphs.

[0164] The terms "User Equipment" (i.e., "UE"), "mobile station", "mobile device", and "wireless device" when used by 3GPP are generally intended to be synonymous with each other and include stand-alone mobile stations such as terminals, cell phones, smartphones, tablets, cellular IoT devices, IoT devices, and machines. It will be understood that the terms "mobile station" and "mobile device" also include devices that remain stationary for long periods of time.

[0165] A UE can be, for example, an item of equipment for production or manufacturing and / or an item of energy-related machinery (such as boilers; engines; turbines; solar panels; wind turbines; hydroelectric generators; thermal power generators; nuclear power generators; batteries; nuclear systems and / or related equipment; heavy electrical machinery; pumps including vacuum pumps; compressors; fans; blowers; hydraulic equipment; pneumatic equipment; metalworking machines; manipulators; robots and / or their application systems; tools; molds or dies; rolls; conveying equipment; elevators; material handling equipment; textile machines; sewing machines; printing and / or related machines; paper processing machines; chemical machines; mining machines and / or construction machines and / or related equipment; machinery and / or appliances for agriculture, forestry, and / or fisheries; safety and / or environmental protection equipment; tractors; precision bearings; chains; gears; power transmission equipment; lubrication equipment; valves; pipe fittings; and / or application systems for any of the aforementioned equipment or machinery).

[0166] A UE can be, for example, an item of transportation equipment (such as transportation equipment like rolled materials; automobiles; motorcycles; bicycles; trains; buses; carts; human-powered vehicles; ships and other watercraft; aircraft; rockets; satellites; drones; balloons, etc.).

[0167] The UE can be an item of information and communication equipment (such as information and communication equipment like electronic computers and related devices; communication and related devices; electronic components, etc.).

[0168] The UE can be, for example, an item of a refrigerator, a refrigerator - applied product, a commodity and / or service - industry equipment, a vending machine, an automatic service machine, an office machine or equipment, a consumer - oriented electronic device, and an electronic device (such as audio equipment; video equipment; loudspeakers; radios; televisions; microwave ovens; rice cookers; coffee machines; dishwashers; washing machines; dryers; electronic fans or related devices; vacuum cleaners, etc. among consumer - oriented electronic devices).

[0169] The UE can be, for example, an electrical - application system or equipment (such as an X - ray system; a particle accelerator; a radioisotope device; a sound - wave device; an electromagnetic - application device; an electric - application device, etc. among electrical - application systems or equipment).

[0170] The UE can be, for example, an electronic lamp, a lighting fixture, a measuring device, an analyzer, a tester, or a surveying or detecting device (such as a smoke alarm; a human - presence sensor; a motion sensor; a wireless tag, etc.), a wristwatch or clock, an inspection device, an optical device, a medical device and / or system, an item of a weapon, a cutting tool, a hand tool, etc.

[0171] The UE can be a portable information terminal or related equipment of wireless equipment (such as a wireless card or module designed to be attached to or inserted into another electronic device (such as a personal computer, an electrical measuring instrument)).

[0172] The UE can be part of a device or system that uses various wired and / or wireless communication technologies to provide applications, services, and solutions described later regarding the Internet of Things (IoT).

[0173] Internet of Things devices (or "things") can be equipped with appropriate electronic devices, software, sensors, network connections, etc. that enable these devices to collect and exchange data with each other and with other communication devices. IoT devices may include automated devices that follow software instructions stored in internal memory. IoT devices can operate without the need for human supervision or interaction. IoT devices may also remain stationary and / or inactive for long periods of time. IoT devices may (generally) be implemented as part of a fixed installation. IoT devices may also be incorporated into non-fixed devices (e.g., vehicles) or attached to animals or people being monitored / tracked.

[0174] It will be understood that IoT technology can be implemented on any communication device that can be connected to a communication network to send / receive data, whether or not such communication devices are controlled by human input or software instructions stored in memory.

[0175] It will be understood that IoT devices are sometimes also referred to as Machine Type Communication (MTC) devices or Machine-to-Machine (M2M) communication devices. It will be understood that a UE can support one or more IoT or MTC applications. Some examples of MTC applications are listed in Table 1 below. This list is not exhaustive and is intended to show some examples of machine type communication applications.

Table 2

[0176] Applications, services, and solutions can be, for example, Mobile Virtual Network Operator (MVNO) services, emergency wireless communication systems, Private Branch eXchange (PBX) systems, PHS / digital cordless communication systems, Point of Sale (POS) systems, advertising call systems, Multimedia Broadcast and Multicast Service (MBMS), Vehicle to Everything (V2X) systems, train wireless systems, location-related services, disaster / emergency wireless communication services, community services, video streaming services, femtocell application services, Voice over LTE (VoLTE) services, charging services, wireless on-demand services, roaming services, activity monitoring services, telecommunications carrier / communication network selection services, feature-limited services, Proof of Concept (PoC) services, personal information management services, ad-hoc network / Delay Tolerant Networking (DTN) services, and the like.

[0177] Furthermore, the UE categories described above are only examples of the application examples of the technical ideas and exemplary embodiments described in this document. Needless to say, these technical ideas and exemplary embodiments are not limited to the UEs described above, and various modifications can be made thereto.

[0178] The method performed by the radio access network node may further include receiving respective configuration information and, based on the respective configuration information, including at least one of a plurality of other radio access network nodes in a list including a plurality of candidate aggressor nodes. In this case, identifying the aggressor node may include identifying the aggressor node from the list.

[0179] Including may be performed based on at least one of location information related to a radio access network node, respective location information related to a transmitter of a candidate aggressor node, and beam characteristics related to the transmitter of the candidate aggressor node.

[0180] The method performed by a radio access network node may further include receiving beam configuration information of at least one other radio access network node. In this case, including at least one of a plurality of other radio access network nodes in the list may be performed based on the beam configuration information.

[0181] The method performed by a radio access network node may further include sending a list to at least one other node for managing the CLI.

[0182] The method performed by a radio access network node may further include receiving a further list including information identifying at least one candidate aggressor node as a source of the CLI of a cell of a further radio access network node, and managing the list based on the further list.

[0183] The method performed by a radio access network node may further include receiving information identifying transmission power related to an aggressor node.

[0184] The configuration information may include at least one of a time-division duplex configuration, a beam configuration, and location information associated with transmitters of a plurality of remote radio access network nodes.

[0185] Identifying an aggressor node may include measuring a CLI or a change in the CLI associated with at least one candidate aggressor node among a plurality of candidate aggressor nodes while the at least one candidate aggressor node is performing a beam sweep operation or a nulling beam sweep operation. The method performed by a radio access network node may further include identifying the beam of the aggressor node as a source of the CLI based on the beam sweep operation or the nulling beam sweep operation.

[0186] Identifying an aggressor node may further include causing at least one candidate aggressor node to report a CLI or a change in the CLI associated with the at least one candidate aggressor node.

[0187] The beam sweep operation may be performed on at least one of a first set of at least one beam currently used by at least one candidate aggressor node for data transmission, a second set of at least one beam expected to be used by at least one candidate aggressor node for data transmission, and a third set of at least one beam not used by at least one candidate aggressor node for data transmission.

[0188] The method performed by a radio access network node may further include configuring at least one resource for measuring the CLI and determining the level of the CLI within a cell of the radio access network node based on the received signal strength of a CLI reference signal received from the aggressor node through the at least one resource.

[0189] The method performed by a radio access network node may further include transmitting beam configuration information of at least one beam of the radio access network node to other radio access network nodes for identifying a source beam of the CLI by the other access network nodes.

[0190] The timing for transmitting at least one reference signal for measuring the CLI may be set such that the arrival time of an uplink signal from a user equipment (UE) to another radio access network node coincides with the arrival time of a radio transmission from the radio access network node.

[0191] In a case where downlink transmissions by a radio access network node and another radio access network node are synchronized, the timing may be set based on a first value representing the arrival time of an uplink signal from the UE and a second value derived based on the distance between the radio access network node and another radio access network node.

[0192] The method performed by the radio access network node may further include receiving information indicating the occurrence of CLI outside the serving area of the radio access network node based on the at least one transmitted reference signal.

[0193] The received signal strength value may include at least one of a CLI Channel State Information - Reference Signal Received Power (CLI CSI - RSRP) value and a base station - specific CLI received signal strength indicator (CLI - RSSI) value.

[0194] The CLI CSI - RSRP value may represent a linear average of the power contributions of at least one resource element of at least one antenna port that transmits a CSI reference signal related to CLI RSRP measurement within a related measurement frequency bandwidth in at least one related CSI - RS opportunity.

[0195] The base station-specific CLI-RSSI value may represent a linear average of the total received power observed in at least one OFDM symbol of at least one associated measurement time resource in an associated measurement bandwidth from at least one source.

[0196] The at least one source may include at least one of a co-channel serving cell, a non-serving cell, a source of adjacent channel interference, a source of self-interference, and thermal noise.

[0197] The at least one resource may include at least one of at least one resource for a Zero Power (ZP) Sounding Reference Signal (SRS), at least one punctured resource, at least one ZP CLI management resource, and at least one ZP Channel State Information - Reference Signal (CSI-RS) resource.

[0198] Configuring may include configuring a plurality of ZP SRS resources for measuring respective CLIs caused by wireless transmissions from a plurality of transmitters. The coaming coefficient of the plurality of ZP SRS resources may be selected based on the maximum number of the plurality of transmitters, and determining may be performed for each of the plurality of transmitters based on the coaming coefficient and a plurality of orthogonal codes in the code domain.

[0199] The at least one resource may include a plurality of ZP SRSs or CSI-RS resources each associated with a different beam, and determining may include determining, for each of the different beams, each level of the CLI based on the corresponding received signal strength value of the CLI reference signal received through the associated ZP SRS or CSI-RS resource.

[0200] The punctured resource may include at least one of a punctured uplink data resource and a punctured SRS resource, and the punctured resource may be configured in at least one of the time and frequency domains.

[0201] At least one resource may be configured in at least one of a periodic, semi-persistent, and dynamic manner.

[0202] The radio access network node may be configured to operate in Sub-Band Full Duplex (SBFD), and at least one resource may be configured in at least one sub-band.

[0203] The information indicating the occurrence of a CLI may include at least one of a CLI Channel State Information - Reference Signal Received Power (CLI CSI-RSRP) value and a CLI received signal strength indicator (CLI-RSSI) value.

[0204] The information indicating the occurrence of a CLI may be transmitted in at least one of a periodic report, a semi-persistent report, and an aperiodic or on-demand report.

[0205] The method performed by the radio access network node may further include receiving a request for transmitting a report regarding the CLI from another radio access network node or an operation management node functioning as a node for managing the CLI, and transmitting a report including the information indicating the occurrence of the CLI to another radio access network node or the operation management node.

[0206] Information indicating the occurrence of CLI may be sent to the node in charge of CLI management in cases where the level of CLI exceeds the associated threshold value.

[0207] Downlink transmissions by a radio access network node and other radio access network nodes may be synchronized. In this case, the timing for transmitting an uplink signal may be set based on a first value representing the arrival time of a downlink signal from another radio access network node and a second value derived based on the distance between the radio access network node and the other radio access network node.

[0208] The timing may be based on the timing advance value of the UE. The timing advance value may be a negative number.

[0209] The method performed by the UE may further include configuring a guard period based on the timing.

[0210] Various other modifications will be apparent to those skilled in the art and are not described in further detail here.

[0211] All or part of the embodiments disclosed above can be described as the following appendices, but are not limited thereto. (Appendix 1) A method performed by a radio access network node, receiving respective configuration information for determining Cross Link Interference (CLI) from at least one other radio access network node, identifying an aggressor node as the source of the CLI within the cell of the radio access network node outside the serving area of the aggressor node based on the respective configuration information and including the method. (Appendix 2) Said identifying is performed by updating a list including information for identifying at least one candidate aggressor node based on said respective configuration information, by including or deleting information for identifying said at least one other radio access network node. Said identifying the aggressor node is performed by identifying the aggressor node from said list. The method according to Appendix 1. (Appendix 3) Said updating is performed based on at least one of position information corresponding to said radio access network node, respective position information corresponding to transmitters of said at least one candidate aggressor node, and characteristics of beams corresponding to transmitters of said at least one candidate aggressor node. The method according to Appendix 2. (Appendix 4) further including receiving respective beam configuration information of said at least one other radio access network node, and said updating is performed based on said respective beam configuration information. The method according to Appendix 2 or 3. (Appendix 5) further including transmitting said list to at least one other node managing said CLI. The method according to any one of Appendices 2 to 4. (Appendix 6) further including receiving a further list including information for identifying at least one candidate aggressor node as a source of a CLI of a cell of a further radio access network node, and updating said list based on said further list. The method according to any one of Appendices 2 to 5 further including the above. (Appendix 7) further including receiving information for identifying transmission power corresponding to said aggressor node, Identifying whether the transmission of the aggressor node interferes with the access network node The method according to any one of Appendices 1 to 6, further comprising the above. (Appendix 8) Each of the configuration information includes Time division duplex configuration, Beam configuration, and Location information corresponding to the transmitter of the at least one other radio access network node including at least one of The method according to any one of Appendices 1 to 7. (Appendix 9) Identifying the aggressor node includes measuring a CLI or a change in the CLI corresponding to the at least one candidate aggressor node while the at least one candidate aggressor node is performing a beam sweep operation or a nulling beam sweep operation The method according to any one of Appendices 2 to 8. (Appendix 10) Identifying the beam of the aggressor node as the source of the CLI based on the beam sweep operation or the nulling beam sweep operation The method according to Appendix 9, further comprising the above. (Appendix 11) Identifying the aggressor node further includes reporting the CLI or the change in the CLI corresponding to the at least one candidate aggressor node to the at least one candidate aggressor node The method according to Appendix 9 or 10. (Appendix 12) The beam sweep operation is a first set of at least one beam currently used for data transmission by the at least one candidate aggressor node, a second set of at least one beam expected to be used for data transmission by the at least one candidate aggressor node, and A third set of at least one beam not used for data transmission by the at least one candidate aggressor node performed for at least one of The method according to any one of Appendices 9 to 11. (Appendix 13) Configuring at least one resource for measuring the CLI, Determining the level of the CLI in the cell of the radio access network node based on the received signal strength of the CLI reference signal received from the aggressor node through the at least one resource The method according to any one of Appendices 1 to 12, further comprising. (Appendix 14) A method performed by a radio access network node, Detecting, based on a reference signal, the occurrence of cross-link interference (CLI) caused by wireless transmission from another radio access network node outside the serving area of the other radio access network node, Transmitting information indicating the occurrence of the CLI to at least one other node that manages the CLI A method comprising. (Appendix 15) The information indicating the occurrence of the CLI is CLI Channel State Information - Reference Signal Received Power (CLI CSI-RSRP) value, and CLI Received Signal Strength Indicator (CLI-RSSI) value including at least one of The method according to Appendix 14. (Appendix 16) The information indicating the occurrence of the CLI is A periodic report, Semi-persistent reports, and Aperiodic or on-demand reports Are transmitted by at least one of The method described in Appendix 14 or 15. (Appendix 17) Receiving, from the other radio access network node, or an operation management node operating as one of the at least one other node managing the CLI, a request to transmit a report including the information indicating the occurrence of the CLI; Transmitting the report to the other radio access network node or the operation management node The method according to any one of Appendices 14 to 16, further comprising. (Appendix 18) The information indicating the occurrence of the CLI is transmitted to the at least one other node managing the CLI in a case where the level of the CLI exceeds a threshold value. The method according to any one of Appendices 14 to 17. (Appendix 19) A method executed by a radio access network node, comprising: Configuring at least one resource for measuring cross-link interference (CLI) caused by wireless transmission from the transmitter outside the serving area of the transmitter of the radio access network node; Determining the level of the CLI based on a received signal strength value of a CLI reference signal received from the transmitter through the at least one resource A method including. (Appendix 20) The received signal strength value is CLI channel state information reference signal received power (CLI CSI-RSRP) value, and Base station specific CLI Received Signal Strength Indicator (CLI-RSSI) value including at least one of the method described in Appendix 19 (Appendix 21) The CLI CSI-RSRP value represents the linear average of the power contributions of at least one resource element of one or more antenna ports that transmit CSI reference signals related to CLI RSRP measurement within the related measurement frequency bandwidth in at least one related CSI-RS opportunity the method described in Appendix 20 (Appendix 22) The base station specific CLI-RSSI value represents the linear average of the total received power observed in at least one orthogonal frequency division multiplexing (OFDM) symbol of at least one related measurement time resource within the related measurement bandwidth from at least one source the method described in Appendix 20 or 21 (Appendix 23) The at least one source includes a co-channel serving cell a non-serving cell a source of adjacent channel interference a source of self-interference, and thermal noise including at least one of the method described in Appendix 22 (Appendix 24) The at least one resource includes at least one resource for a zero power (ZP) sounding reference signal (SRS) at least one punctured resource at least one ZP-CLI management resource, and ​At least one ZP channel state information reference signal (CSI-RS) resource including at least one of them The method according to any one of Appendices 19 to 23 (Appendix 25) Said configuring includes configuring a plurality of ZP SRS resources for measuring respective CLIs caused by wireless transmissions from a plurality of transmitters, The coaming coefficient of the plurality of ZP SRS resources is selected based on the maximum number of the plurality of transmitters, Said determining is performed for each of the plurality of transmitters based on the coaming coefficient and a plurality of orthogonal codes within the code domain The method according to Appendix 24 (Appendix 26) Said at least one resource includes a plurality of ZP SRS or CSI-RS resources respectively associated with different beams, Said determining includes, for each of the different beams, determining the respective level of the CLI based on the corresponding received signal strength value of the CLI reference signal received through the associated ZP SRS or CSI-RS resource The method according to Appendix 24 (Appendix 27) Said punctured resource includes at least one of a punctured uplink data resource and a punctured SRS resource, and said punctured resource is configured in at least one of the time and frequency domains The method according to Appendix 24 (Appendix 28) Said at least one resource is configured in at least one of a periodic, semi-persistent, and dynamic manner, The method according to any one of Appendices 19 to 27 (Appendix 29) The wireless access network node is configured to operate in Sub-Band Full Duplex (SBFD) mode, The at least one resource is configured in at least one sub-band. The method according to appendix 24 or 27. (Appendix 30) A method performed by a wireless access network node, Transmitting a reference signal for measuring Cross Link Interference (CLI) caused by a wireless transmission from the wireless access network node outside the serving area of the wireless access network node A method including this. (Appendix 31) Transmitting beam configuration information of at least one beam of the wireless access network node to another wireless access network node for use in identifying a source beam of the CLI by the other wireless access network node The method according to appendix 30 further including this. (Appendix 32) The timing of transmitting the reference signal for measuring CLI is set such that the arrival time of an uplink signal from a User Equipment (UE) at another wireless access network node coincides with the arrival time of the wireless transmission from the wireless access network node The method according to appendix 30 or 31. (Appendix 33) The downlink transmissions by the wireless access network node and the other wireless access network node are synchronized, The timing is set based on a first value representing the arrival time of the uplink signal from the UE and a second value derived based on the distance between the wireless access network node and the other wireless access network node The method according to appendix 32. (Appendix 34) Receiving information indicating the occurrence of CLI outside the serving area of the radio access network node based on the reference signal The method according to any one of appendices 30 to 33 further comprising this (Appendix 35) A method performed by a User Equipment (UE), comprising: Transmitting an uplink signal such that an arrival time of the uplink signal at a radio access network node matches an arrival time of a reference signal from another radio access network node for measuring Cross Link Interference (CLI) A method comprising this (Appendix 36) Downlink transmissions by the radio access network node and the other radio access network node are synchronized, and a timing for transmitting the uplink signal is set based on a first value representing the arrival time of a downlink signal from the other radio access network node and a second value derived based on a distance between the radio access network node and the other radio access network node The method according to appendix 35 (Appendix 37) The timing is based on a timing advance value of the UE The method according to appendix 35 or 36 (Appendix 38) The timing advance value is a negative number The method according to appendix 37 (Appendix 39) Configuring a guard period based on the timing The method according to any one of appendices 36 to 38 further comprising this (Appendix 40) A radio access network node, means for receiving respective configuration information for determining Cross Link Interference (CLI) from at least one other radio access network node; means for identifying an aggressor node as the source of the CLI within a cell of the radio access network node outside the serving area of the aggressor node based on the respective configuration information; A radio access network node comprising the above. (Appendix 41) A radio access network node, means for detecting, based on a reference signal, the occurrence of Cross Link Interference (CLI) caused by a wireless transmission from another radio access network node outside the serving area of the other radio access network node; means for transmitting information indicating the occurrence of the CLI to at least one other node that manages the CLI; A radio access network node comprising the above. (Appendix 42) A radio access network node, means for configuring at least one resource for measuring Cross Link Interference (CLI) caused by a wireless transmission from a transmitter of the radio access network node outside the serving area of the transmitter; means for determining the level of the CLI based on a received signal strength value of a CLI reference signal received from the transmitter through the at least one resource; A radio access network node comprising the above. (Appendix 43) A radio access network node, means for transmitting a reference signal for measuring Cross Link Interference (CLI) caused by a wireless transmission from the radio access network node outside the serving area of the radio access network node; A radio access network node comprising (Appendix 44) A user equipment (UE) comprising means for transmitting an uplink signal such that an arrival time of the uplink signal at the radio access network node coincides with an arrival time of a reference signal for measuring cross link interference (CLI) from another radio access network node A user equipment comprising

[0212] As is widely described, it will be understood by those skilled in the art that many variations and / or modifications can be made to the present disclosure without departing from the spirit or scope of the present disclosure, as shown in the specific embodiments. Therefore, this embodiment is considered to be illustrative in all respects and not restrictive.

[0213] This application claims the benefit of priority based on UK Patent Application No. 2209320.7 filed on Jun. 24, 2022, the entire content of which is incorporated herein by reference.

Explanation of Signs

[0214] 1 Telecommunication system 3, 3A, 3B Mobile device 5, 5A, 5B, 5C, 5D, 5E Base station 7 Core network 31 Transceiver circuit 33 Antenna 35 User interface 37 Controller 39 Memory 41 Operating system 43 Communication control module 45 CLI management module 51 Transceiver circuit 53 Antenna 55 Network interface 57 Controller 59 Memory 61 Operating System 63 Communication Control Module 65 CLI Management Module 71 Transceiver Circuit 75 Network Interface 77 Controller 79 Memory 81 Operating System 83 Communication Control Module 85 CLI Management Module

Claims

1. A method performed by a radio access network node, comprising: receiving respective configuration information for determining cross link interference (CLIs) from at least one other radio access network node; identifying an aggressor node based on the respective configuration information as a source of the CLI within a cell of the radio access network node outside a serving area of the aggressor node; and a method including the above.

2. The identifying is performed by updating a list including information for identifying at least one candidate aggressor node based on the respective configuration information, including or deleting information for identifying the at least one other radio access network node, and the identifying the aggressor node is performed by identifying the aggressor node from the list. The method according to claim 1.

3. The updating is performed based on at least one of position information corresponding to the radio access network node, respective position information corresponding to a transmitter of the at least one candidate aggressor node, and beam characteristics corresponding to a transmitter of the at least one candidate aggressor node. The method according to claim 2.

4. The method further includes receiving respective beam configuration information of the at least one other radio access network node, and the updating is performed based on the respective beam configuration information. The method according to claim 2 or 3.

5. The method further includes transmitting the list to at least one other node for managing the CLI. The method according to any one of claims 2 to 4.

6. The method further includes receiving a further list including information for identifying at least one candidate aggressor node as a source of a CLI in a cell of a further radio access network node, and updating the list based on the further list. The method according to any one of claims 2 to 5.

7. The method further includes receiving information for identifying transmission power corresponding to the aggressor node, and identifying whether transmission of the aggressor node interferes with the access network node. The method according to any one of claims 1 to 6. ​

8. each of the respective configuration information is time-division duplex configuration, beam configuration, and position information corresponding to a transmitter of the at least one other radio access network node including at least one of The method according to any one of claims 1 to 7.

9. Identifying the aggressor node includes measuring a CLI or a change in the CLI corresponding to the at least one candidate aggressor node while the at least one candidate aggressor node is performing a beam sweep operation or a nulling beam sweep operation The method according to any one of claims 2 to 8.

10. further comprising identifying the beam of the aggressor node as a source of the CLI based on the beam sweep operation or the nulling beam sweep operation The method according to claim 9.

11. Identifying the aggressor node further includes reporting the CLI or the change in the CLI corresponding to the at least one candidate aggressor node to the at least one candidate aggressor node The method according to claim 9 or 10.

12. The beam sweep operation is a first set of at least one beam currently used for data transmission by the at least one candidate aggressor node, a second set of at least one beam expected to be used for data transmission by the at least one candidate aggressor node, and a third set of at least one beam not used for data transmission by the at least one candidate aggressor node performed for at least one of The method according to any one of claims 9 to 11.

13. configuring at least one resource for measuring the CLI, and determining a level of the CLI within the cell of the radio access network node based on a received signal strength of a CLI reference signal received from the aggressor node through the at least one resource The method according to any one of claims 1 to 12, further comprising.

14. A method performed by a radio access network node, comprising Outside the serving area of other radio access network nodes, detecting the occurrence of cross-link interference (Cross Link Interference: CLI) caused by wireless transmissions from said other radio access network nodes based on reference signals; transmitting information indicating said occurrence of said CLI to at least one other node that manages said CLI; A method comprising.

15. The information indicating the occurrence of said CLI is CLI Channel State Information - Reference Signal Received Power (CLI CSI-RSRP) value, and CLI Received Signal Strength Indicator (CLI-RSSI) value including at least one of The method according to claim 14.

16. The information indicating the occurrence of said CLI is periodic report, semi-persistent report, and aperiodic or on-demand report transmitted in at least one of The method according to claim 14 or 15.

17. Receiving a request to transmit a report including the information indicating the occurrence of said CLI from the other radio access network node or an operation management node operating as one of said at least one other node that manages said CLI; transmitting said report to said other radio access network node or said operation management node; The method according to any one of claims 14 to 16, further comprising.

18. The information indicating the occurrence of said CLI is transmitted to said at least one other node that manages said CLI in cases where the level of said CLI exceeds a threshold value. The method according to any one of claims 14 to 17.

19. A method performed by a radio access network node, comprising: configuring at least one resource for measuring cross-link interference (Cross Link Interference: CLI) caused by wireless transmissions from a transmitter of said radio access network node outside the serving area of said transmitter; Determining the level of the CLI based on the received signal strength value of the CLI reference signal received from the transmitter through the at least one resource A method comprising.

20. The received signal strength value is CLI Channel State Information - Reference Signal Received Power (CLI CSI-RSRP) value, and CLI Received Signal Strength Indicator (CLI-RSSI) value specific to the base station including at least one of The method according to claim 19.

21. The CLI CSI-RSRP value represents a linear average of the power contributions of at least one resource element of at least one antenna port that transmits a CSI reference signal related to CLI RSRP measurement within a related measurement frequency bandwidth in at least one related CSI-RS opportunity The method according to claim 20.

22. The CLI-RSSI value specific to the base station represents a linear average of the total received power observed in at least one orthogonal frequency division multiplexing (OFDM) symbol of at least one related measurement time resource within a related measurement bandwidth from at least one source The method according to claim 20 or 21.

23. The at least one source is a co-channel serving cell, a non-serving cell, a source of adjacent channel interference, a source of self-interference, and thermal noise including at least one of The method according to claim 22.

24. The at least one resource is at least one resource for a Zero Power (ZP) sounding reference signal (Sounding Reference Signal: SRS), at least one punctured resource, at least one ZP-CLI management resource, and at least one ZP Channel State Information - Reference Signal (CSI-RS) resource including at least one of The method according to any one of claims 19 to 23.

25. Said constituting includes constituting a plurality of ZP SRS resources for measuring respective CLIs caused by wireless transmissions from a plurality of transmitters, The coaming coefficient of the plurality of ZP SRS resources is selected based on the maximum number of the plurality of transmitters, Said determining is performed for each of the plurality of transmitters based on the coaming coefficient and a plurality of orthogonal codes within the code domain The method according to claim 24.

26. The at least one resource includes a plurality of ZP SRS or CSI-RS resources respectively associated with different beams, Said determining includes, for each of the different beams, determining each level of the CLI based on a corresponding received signal strength value of a CLI reference signal received through the associated ZP SRS or CSI-RS resource The method according to claim 24.

27. The punctured resource includes at least one of a punctured uplink data resource and a punctured SRS resource, and the punctured resource is configured in at least one of a time and a frequency domain The method according to claim 24.

28. The at least one resource is configured in at least one of a periodic, semi-persistent, and dynamic manner, The method according to any one of claims 19 to 27.

29. The radio access network node is configured to operate in sub-band full duplex (SBFD), The at least one resource is configured in at least one sub-band The method according to claim 24 or 27.

30. A method performed by a radio access network node, Transmitting a reference signal for measuring cross link interference (CLI) caused by wireless transmission from the radio access network node outside the serving area of the radio access network node A method including.

31. transmitting, to another radio access network node, beam configuration information of at least one beam of the radio access network node for use in identifying a source beam of the CLI by the other radio access network node The method according to claim 30, further comprising **Claim 32** The timing of transmitting the reference signal for measuring the CLI is set such that the arrival time of an uplink signal from a user equipment (UE) at another radio access network node coincides with the arrival time of the radio transmission from the radio access network node The method according to claim 30 or 31 **Claim 33** downlink transmissions by the radio access network node and the other radio access network node are synchronized the timing is set based on a first value representing the arrival time of the uplink signal from the UE and a second value derived based on the distance between the radio access network node and the other radio access network node The method according to claim 32 **Claim 34** receiving, based on the reference signal, information indicating the occurrence of CLI outside the serving area of the radio access network node The method according to any one of claims 30 to 33, further comprising **Claim 35** A method performed by a user equipment (UE), comprising transmitting an uplink signal such that the arrival time of the uplink signal at a radio access network node coincides with the arrival time of a reference signal for measuring cross link interference (CLI) from another radio access network node A method comprising **Claim 36** downlink transmissions by the radio access network node and the other radio access network node are synchronized the timing of transmitting the uplink signal is set based on a first value representing the arrival time of a downlink signal from the other radio access network node and a second value derived based on the distance between the radio access network node and the other radio access network node The method according to claim 35 **Claim 37** The timing is based on the timing advance value of the UE The method according to claim 35 or 36 **Claim 38** The timing advance value is a negative number The method according to claim 37 **Claim 39** Configuring a guard period based on the timing The method according to any one of claims 36 to 38, further comprising **Claim 40** A radio access network node, comprising means for receiving respective configuration information from at least one other radio access network node for determining cross link interference (CLIs); means for identifying an aggressor node as a source of the CLIs within a cell of the radio access network node outside a serving area of the aggressor node, based on the respective configuration information A radio access network node comprising the above **Claim 41** A radio access network node, comprising means for detecting, outside a serving area of another radio access network node, an occurrence of cross link interference (CLIs) caused by a wireless transmission from the other radio access network node, based on a reference signal; means for transmitting information indicating the occurrence of the CLIs to at least one other node that manages the CLIs A radio access network node comprising the above **Claim 42** A radio access network node, comprising means for configuring at least one resource for measuring cross link interference (CLIs) caused by a wireless transmission from a transmitter of the radio access network node, outside a serving area of the transmitter; means for determining a level of the CLIs based on a received signal strength value of a CLI reference signal received from the transmitter through the at least one resource A radio access network node comprising the above **Claim 43** A radio access network node, comprising means for transmitting a reference signal for measuring cross link interference (CLIs) caused by a wireless transmission from the radio access network node, outside a serving area of the radio access network node A radio access network node comprising the above

44. A user equipment (UE), means for transmitting an uplink signal such that the arrival time of the uplink signal at a radio access network node coincides with the arrival time of a reference signal for measuring cross link interference (CLIs) from another radio access network node A user equipment comprising the same.

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