A method for measuring intra-cell inter-subband cross-link interference

Abstract

The invention relates to a method for measuring intra-cell inter-subband cross-link interference (CLI) between user equipment (UEs) (10) in Subband Full-Duplex (SBFD) networks (30). The method includes configuring UEs (10) by a network entity (20) to transmit Sounding Reference Signals (SRS) using frequency / code division multiplexing, and determining whether the transmission channel exhibits reciprocity. If reciprocity is absent, CLI measurements are performed using a binary splitting method, and results are reported to the network entity (20). UEs (10) are grouped based on interference values within a reference range, and full bandwidth time-division multiplexed SRS transmissions are configured such that one UE (10) transmits while others measure interference. The method further includes determining if a URLLC UE (60) has a pending transmission; if none is present, CLI values of each group are identified, and UEs (10) exceeding an aggressor reference value are reported to the network entity (20).

Description

[0001] DESCRIPTION

[0002] A METHOD FOR MEASURING INTRA-CELL INTER-SUBBAND CROSS-LINK INTERFERENCE

[0003] TECHNICAL FIELD

[0004] The invention relates to a method for measuring intra-cell inter-sub-band cross-link interference in Sub-band Full-Duplex (SBFD) networks.

[0005] PRIOR ART

[0006] In current communication systems, especially in Subband Full-Duplex (SBFD) and Dynamic Time Division Duplexing (D-TDD) networks, cross-link interference (CLI) emerges as a significant technical issue. CLI occurs due to signal interactions between user equipment (UE), resulting in unwanted signal transmission between devices sharing the same frequency band. This situation leads to performance losses, especially in applications requiring ultra-reliable low-latency communication (URLLC). Different techniques have been developed to effectively measure and manage CLI. However, current solutions are not sufficient in terms of detecting the interference source with precision, providing low-latency communication and increasing energy efficiency.

[0007] Most of the methods developed for CLI measurement are based on single-step processes. In these methods, user equipment performs CLI measurement in accordance with the SRS configurations determined by the base station and reports the obtained data. However, this technique is time and resource in-efficient. Especially in dynamic network conditions, it is not possible to quickly detect aggressive interference sources with single-step measurement processes.

[0008] Another method frequently used in existing techniques is bitmap-based resource allocation. In this method, which user equipment will transmit SRS and which will perform CLI measurement is determined by a central controller. However, this approach fails to adapt quickly to dynamic network conditions and negatively impactsenergy efficiency due to unnecessary resource allocation. In scenarios with increased network density, solutions based on static resource allocation become insufficient, necessitating more flexible methods.

[0009] In some existing techniques, user equipment is provided to perform CLI measurements by sharing common SRS resources. This method aims to increase the overall efficiency of the system. However, it is seen that this approach reduces measurement accuracy and leads to incorrect estimates in high-interference environments. Accurate determination of interference levels is of great importance, especially in dense cellular networks.

[0010] In previous techniques, there is no specific mechanism for prioritizing user equipment to meet ultra-reliable low-latency communication requirements. Existing solutions require all user equipment to undergo the same measurement processes. This leads to unexpected delays and reliability problems in communication scenarios that require low latency. Optimizations are required to perform CLI measurements faster and more accurately for URLLC services.

[0011] When evaluated in terms of energy efficiency, it is seen that most of the existing methods are insufficient to prevent unnecessary signal transmissions. In CLI measurements, all user equipment is generally required to transmit SRS at certain times. User equipment that does not cause interference also makes unnecessary transmissions during this process. This increases the total energy consumption of the system and reduces the efficiency of the communication infrastructure in the long term. Therefore, more effective mechanisms are needed to ensure that only devices that cause interference transmit SRS.

[0012] There are also certain limitations in measurement accuracy in existing techniques. It is of great importance to correctly identify the source of interference and to perform the measurement process with high accuracy. However, commonly used methods only perform a general CLI assessment and do not provide a detailed interference analysis. Most systems do not have a layered or two-stage measurement mechanism, which makes it difficult to perform precise interference management.Application document US20240162972 discloses a method for inter-user equipment CLI management, focusing on reducing the complexity and overhead associated with managing interference in wireless networks. The invention introduces joint SRS transmission and CLI measurement configurations for multiple UEs, which helps manage CLI more efficiently. Specifically, it addresses both intra-cell and inter-cell CLI by allocating resources dynamically for SRS transmissions and performing CLI measurements across subsets of UEs. The method involves the use of coordinated scheduling between neighboring cells, as well as joint SRS configurations, to reduce the overhead and ensure efficient CLI measurement. In this method, detailed prioritization and layered CLI measurement approach are not mentioned.

[0013] All the problems mentioned above have made it necessary to make an innovation in the relevant technical field as a result.

[0014] BRIEF DESCRIPTION OF THE INVENTION

[0015] The present invention relates to a method to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field.

[0016] An object of the invention is to provide a method for measuring and managing intra-cell sub-band cross-link interference (CLI) in Sub-band Full-Duplex (SBFD) networks to optimize network performance.

[0017] To achieve all the objects mentioned above and that will emerge from the following detailed description, a method for measuring intra-cell inter-subband cross-link interference (CLI) occurring between user equipment (UEs) in Subband Full-Duplex (SBFD) networks. Accordingly, it comprises the steps of configuring the UEs by the network entity to transmit Sounding Reference Signal (SRS) using frequency / code division multiplexing, evaluating whether the transmission channel exhibits reciprocity characteristics, in case it is determined that the transmission channel does not exhibit reciprocity characteristics, performing CLI measurements among the UEs in the network using a binary splitting method, reporting the CLI measurements to thenetwork entity, grouping all UEs in the network by the network entity in such a manner that UEs with interference values close to each other within a reference value range are placed in the same group, configuring full bandwidth time-division multiplexing Sounding Reference Signal transmissions in each group such that only one UE transmits and the others measure interference, determining whether there exists a URLLC User Equipment (URLLC UE) with a pending transmission in the network, in case it is determined that no URLLC UE is present in the network, identifying the CLI values of the UEs within each group, reporting to the network entity those UEs in the group whose CLI values exceed an aggressor reference value.

[0018] A possible embodiment of the invention is characterized comprising the steps of; configuring the UEs by the network entity to transmit Sounding Reference Signal using frequency / code division multiplexing is performed as periodic, semi-persistent, or aperiodic.

[0019] Another possible embodiment of the invention is characterized comprising the steps of performing CLI measurements using a binary splitting method among the UEs in the network, in case it is determined that the transmission channel does not exhibit reciprocity characteristics, the following sub-steps are followed to perform CLI measurement based on the binary splitting method:

[0020] calculating a total time interval according to the total number of UEs in the network and the number of sub-time intervals constituting the total time interval, dividing each of the sub-time intervals into a first time interval and a second time interval, dividing the UEs grouped together into a first UE group and a second UE group, at the initial time of each sub-time interval, transmitting the Sounding Reference Signal by the first UE group and measuring the interference values of the UEs in the second UE group based on the Sounding Reference Signal received from the first UE group, in the first time interval of the sub-time interval, transmitting the Sounding Reference Signal by the second UE group and measuring the interference values of the UEs in the first UE group based on the Sounding Reference Signal received from the second UE group, in the second time interval of the sub-time interval, obtaining the interference measurements of all UEs in the network by repeating the above steps for the number of sub-time intervals.Another possible embodiment of the invention is characterized comprising that in case the transmission channel is determined to exhibit reciprocity characteristics after evaluating whether it exhibits reciprocity characteristics, performing the CLI measurement using a reciprocity-based method.

[0021] Another possible embodiment of the invention is characterized comprising the steps of performing CLI measurement using a reciprocity-based method, in case the transmission channel is determined to exhibit reciprocity characteristics, the following sub-steps are followed to perform CLI measurement based on the reciprocity method: calculating a total time interval according to the total number of UEs in the network and the number of sub-time intervals constituting the total time interval, dividing each of the sub-time intervals into a first time interval and a second time interval, dividing the active UEs into a first UE group and a second UE group, at the initial time of each sub-time interval, transmitting the Sounding Reference Signal by the first UE group and measuring the CLI values of the UEs in the second UE group according to the Sounding Reference Signal received from the first UE group, in the first time interval, estimating the CLI values of the UEs in the first UE group by inference, based on the signals received by the UEs in the second UE group during the first time interval, in the second time interval, obtaining the interference measurements of all UEs in the network by repeating the above steps for the number of sub-time intervals.

[0022] Another possible embodiment of the invention is characterized comprising the steps of reporting the CLI measurements to the network entity, the following sub-steps are followed to perform the reporting: collecting the CLI measurements by the receiving UEs, generating the reports by organizing the collected CLI measurements either as CLI matrices or as a limited data set including the identities of aggressor UEs whose values exceed an aggressor reference value.

[0023] Another possible embodiment of the invention is characterized comprising the steps of grouping all UEs in the network by the network entity such that UEs with interference values close to each other within a reference value range are placed in the same group,location-based information or relative signal characteristics information can also be used.

[0024] Another possible embodiment of the invention is characterized comprising the steps of prioritizing the URLLC transmission by disabling Sounding Reference Signal transmission for all UEs in the group in which a URLLC User Equipment (URLLC UE) is determined to be present in the network.

[0025] BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a drawing illustrating schematic view of the dividing sub-groups user equipment groups in sub-time interval

[0027] Figure 2 is a drawing illustrating schematic view of the network.

[0028] Figure 3 is a drawing illustrating schematic view of the proposed method under the existence of a URLLC user equipment.

[0029] Figure 4 is a drawing illustrating a schematic view of the operational flow of the proposed method.

[0030] REFERENCE NUMBERS GIVEN IN THE FIGURE

[0031] 10 User equipment

[0032] 20 Network entity

[0033] 30 Network

[0034] 40 Total number of user equipment

[0035] 50 Aggressor user equipment

[0036] 60 URLLC user equipment

[0037] t Sub-time interval

[0038] tO Initial time

[0039] t1 First time interval

[0040] t2 Second time intervalSRS Sounding Reference Signal

[0041] DETAILED DESCRIPTION OF THE INVENTION

[0042] In this detailed description, the subject matter is explained with references to examples without forming any restrictive effect only in order to make the subject more understandable.

[0043] The invention relates to a method for measuring intra-cell intra-subband cross-link interference (CLI) occurring between user equipment (UEs) (10) in Subband Full Duplex (SBFD) systems. The method aims to improve measurement accuracy, enhance energy efficiency by minimizing measurement duration and resource consumption, and provide low-latency and prioritized measurement capability for URLLC UEs (60). The CLI measurement method is performed in two steps, comprising dynamic UE (10) grouping and URLLC-oriented prioritization. Thus, the overall performance of the system is improved.

[0044] As the first step of the method, the CLI measurement process can be initiated centrally by the network entity (20), or the process can also be triggered by the user equipment (10) itself. In particular, when a predefined event occurs in the network (30), such as a sudden drop in the signal strength of a specific UE (10), the relevant UE (10) can detect this condition and initiate the CLI measurement process. For example, if the signal level received by a UE (10) falls below a certain threshold, this may indicate that the condition is caused by CLI. Thus, the measurement mechanism is activated. Thanks to this flexible initiation mechanism, both reactive and proactive CLI management becomes possible. The method can adapt not only based on centralized decisions but also in accordance with real-time network (30) conditions. This allows rapid action to be taken to mitigate the effects of interference while ensuring continuity in network (30) performance. The network entity (20) described herein may be a base station, a gNB, a central controller, etc. The examples given should not be limited to these.

[0045] In the second step of the method, the network entity (20) configures all UEs (10) or a specific subset of UEs (10) to transmit Sounding Reference Signals (SRS) usingfrequency or code division multiplexing. Through this configuration allows each UE (10) to transmit the Sounding Reference Signal (SRS) in the same time interval without overlapping. For example, in a frequency division structure, different frequency segments within the bandwidth are allocated to each UE (10), enabling simultaneous transmission. This configuration process is designed to be compatible with different timing strategies. Sounding Reference Signals (SRS) transmission can be set as periodic, semi-persistent, or aperiodic. This flexibility allows for optimal scheduling according to network (30) traffic load and application scenarios. For instance, in low traffic conditions, periodic Sounding Reference Signals (SRS) configuration may be preferred, while in environments where sudden changes are expected, aperiodic transmission can be used to enable a more flexible response.

[0046] In this step, UEs (10) can perform Sounding Reference Signals (SRS) transmission using their most up-to-date downlink (DL) and uplink (UL) beam directions according to the current channel conditions. Alternatively, the network entity (20) can configure UEs (10) with multiple beams, enabling the UEs (10) to perform beam sweeping in order to detect CLI levels from different directions. Especially in multi-antenna systems, this beam sweeping process helps to understand the directional characteristics of interference and improves measurement accuracy. Thus, it becomes possible for UEs (10) to create a more comprehensive interference map by receiving and transmitting signals from multiple directions, not only from fixed directions This detailed measurement infrastructure lays the groundwork for the aggressor detection and grouping operations to be explained in the next steps.

[0047] With the configuration of the UEs (10), the reciprocity property of the transmission channel is evaluated. Reciprocity refers to the symmetry of the uplink (UL) and downlink (DL) paths. In order to perform interference measurements between user equipment (10) more effectively, the binary splitting method is used. This method divides the UEs (10) into two subsets at each iteration of the measurement process. While the first subset performs Sounding Reference Signals (SRS) transmission, the second subset receives these transmissions and performs CLI measurement. In this way, the interference effect of each UE (10) on others can be measured systematicallyand in a balanced manner. However, this step is implemented in two different ways depending on whether the transmission channel exhibits the reciprocity property or not.

[0048] If the transmission channel does not exhibit reciprocity, i.e. if the characteristics of the UL and DL channels are different, the UEs (10) are divided into two groups in each sub-time interval (t) and separate measurements are performed in each sub-time interval (t).

[0049] For this purpose firstly, a total time interval is calculated from the total number of UEs (40) in the network (30) and the number of sub-time intervals (t) forming the total time interval is calculated. In a preferred embodiment of the invention, a mathematical equation is used for this calculation. For example, if there are 8 user equipment (10) in the network (30) and the total time interval is 6 milliseconds, the number of sub-time intervals (t) is determined as 3. Each sub-time interval (t) is divided into a first time interval (t1) and a second time interval (t2). Thus, each sub-time interval (t) is divided into two different time periods so that the user equipment (10) transmits and receives in different time periods. At time tO of each sub-time interval (t), the user equipment (10) in a group is divided into two user equipment (10) groups as a first user equipment (10) group and a second user equipment (10) group. Here, as shown in Figure 1, at the beginning of the first sub-time interval (t), all user equipment (10) in the network (30) are divided into two groups. Then, at the beginning of the second sub-time interval (t), the user equipment (10) previously divided into two groups are further divided into two separate groups. Then, at the beginning of the third sub-time interval (t), each of these four separate groups is divided into two sub-groups. This process of dividing the user equipment (10) into two continues until each user equipment (10) is individually separated. In other words, this process is applied as many times as the number of subtime intervals (t).

[0050] In the first time interval (t1) of the sub-time interval (t), the first user equipment (10) group transmits the Sounding Reference Signal (SRS), and the second user equipment (10) group measures the interference values of the user equipment (10) in the first user equipment (10) group based on the Sounding Reference Signal (SRS) received from the first user equipment (10) group. That is, while the first userequipment (10) group transmits frequency / code division multiplexed Sounding Reference Signals (SRS), the second user equipment (10) group receives these orthogonal Sounding Reference Signals (SRS). In the second time interval (t2) of the sub-time interval (t), the second user equipment (10) group transmits the Sounding Reference Signal (SRS), and the first user equipment (10) group measures the interference values of the user equipment (10) in the second user equipment (10) group based on the Sounding Reference Signal (SRS) received from the second user equipment (10) group. These operations continue until the interference value of each user equipment (10) is obtained, that is, for the number of sub-time intervals (t). In this way, each UE (10) performs CLI measurement both as a receiver and as a transmitter, and all possible interference combinations are evaluated.

[0051] In the first time interval (t1) of the sub-time interval (t), the first user equipment (10) group transmits the Sounding Reference Signal (SRS), and the second user equipment (10) group measures the interference values of the user equipment (10) in the first user equipment (10) group according to the Sounding Reference Signal (SRS) received from the first user equipment (10) group. That is, while the first user equipment (10) group transmits frequency / code division multiplexed SRS, the second user equipment (10) group receives these orthogonal Sounding Reference Signals (SRS) signals. In the second time interval (t2) of the sub-time interval (t), the second user equipment (10) group transmits the Sounding Reference Signal (SRS), and the first user equipment (10) group measures the interference values of the user equipment (10) in the second user equipment (10) group according to the Sounding Reference Signal (SRS) received from the second user equipment (10) group. This process continues until the interference value of each user equipment (10) is obtained that is, for the number of sub-time intervals (t). Thus, each UE (10) performs CLI measurements in both transmitter and receiver roles and all possible interference combinations are evaluated.

[0052] On the other hand, in cases where the channel exhibits the reciprocity property, the process becomes simpler. In this scenario, it is sufficient for only one group of UEs (10) to perform Sounding Reference Signals (SRS) transmission in each iteration. This is because the other UEs (10) receiving these signals can estimate the interferencethat the opposite group (in t2 time interval) would receive when they transmit their own Sounding Reference Signals (SRS), due to reciprocity. In other words, it is not necessary for both groups to transmit separately; even if the measurement is performed unidirectionally, bidirectional information is obtained. This situation provides significant savings in both time and transmission resources. The different operating conditions explained above based on reciprocity allow the system to be flexibly configured according to the current channel conditions and make the interference measurement process both comprehensive and efficient.

[0053] Following the CLI measurement process, the CLI data obtained by the receiving user equipment (10) (UEs) are systematically collected and processed for reporting to the network entity (20). In this step, each receiving UE (10) compiles its measured CLI values and generates a report. While generating the reports, two different methods can be used as preparing CLI matrices or reporting the UEs (10) detected based on an agressor threshold value. The CLI matrix structure presents all mutual interference relationships between UEs (10) in detail to the network entity (20). In the thresholdbased UE (10) reporting method, only a limited data set is presented in which the identities of UEs (10) with CLI levels above an aggressor reference value are reported. In the method, each UE (10) determines a threshold value and reports only the interference sources — i.e., the aggressor UEs (50) — that exceed this value. For example, a UE with a CLI value exceeding a specified reference threshold of -80 dBm is marked as an aggressor, and only these identities are reported to the network entity (20). This method minimizes the communication load over the control channel by reducing report volume without compromising measurement accuracy. The network entity (20) collects the reports of all UEs (10) by scheduling them. Thus, the reports are collected regularly in the system without overlapping.

[0054] Following the reporting of CLI measurements, the network entity (20) groups all user equipment (UE) (10) into groups. This grouping process is carried out based on the measured CLI values between each UE (10) and other UEs (10). The main principle is that UEs (10) with interference levels as close to each other as a certain reference value are placed in the same group. In this way, UEs (10) with similar interference environments are evaluated together, and resource planning becomes more efficient.During the grouping process, not only the measured CLI values but also additional side information can be taken into consideration. These additional parameters may include the physical locations of the UEs (10), relative signal strength differences, and channel characteristics. These parameters should not be limited to what is written here. For example, UEs (10) located in the same geographical region and having similar channel conditions may be evaluated under the same group even if their measured CLI levels are not very close to each other. In this way, the method can achieve a more holistic interference analysis without relying only on numerical measurement data. This grouping is the basis for the next step of time-division multiplexing Sounding Reference Signals (SRS) transmission. Thus, simultaneous transmission between groups is enabled, and the system’s resource utilization is optimized.

[0055] Referring to Figure 2, following the grouping process, full bandwidth time-division multiplexing SRS transmission is configured for each group. In this step, only one UE (10) within each group performs Sounding Reference Signals (SRS) transmission during a specific time interval, while the other UEs (10) in the group receive this signal and perform interference measurement. This structure prevents interference between the UEs (10) in the same group and enables more precise and discriminable CLI measurements.

[0056] For example, if there are three UEs (10) in a group, in the first time interval (t1), only UE1 performs Sounding Reference Signals (SRS) transmission, while UE2 and UE3 listen to this signal and measure CLI. In the next time interval, UE2 transmits, and the others perform measurement, and this cycle is completed for all group members. In this way, each UE (10) accurately evaluates the mutual CLI impact with all other UEs (10) within the group.

[0057] This configuration also allows different groups to perform simultaneous SRS transmission based on low interference levels between the groups. While a timedivision multiplexing sequence is applied among UEs (10) within a group, different groups can transmit Sounding Reference Signals (SRS) simultaneously. This is because previous CLI measurements have shown that there is no significantinterference between these groups. Thus, the system achieves high-accuracy measurement while also reducing the total measurement duration, thereby providing time and resource efficiency. Moreover, inter-group simultaneity enables parallelism in spectrum usage, increasing network (30) capacity.

[0058] Following the full bandwidth time-division multiplexing Sounding Reference Signals (SRS) transmission step, the method enables the determination of whether there is a URLLC UE (60) with a pending transmission in the network (30). This check supports the system's structure that prioritizes URLLC services in order to meet low-latency and high-reliability communication requirements. If a UE (10) with URLLC capability and a pending transmission exists in the network (30), all Sounding Reference Signals (SRS) transmission and measurement configurations of the other UEs (10) in the same group as this UE (10) are cancelled. That is, only the URLLC UE (60) remains active in this group, and the measurement process is terminated. This ensures that the URLLC UE (60) can proceed to data transmission without being affected by the measurement process delay. In this way, the system supports the low-latency objective critical for URLLC services and ensures service continuity in mission-critical applications.

[0059] If it is determined that there is no URLLC UE (60) in the network (30), the UEs (10) within the groups continue the CLI measurement process in a time-division multiplexing manner. In this scenario, each of the previously grouped UEs (10) transmits SRS in turn within its group, and the other group members perform CLI measurement using these signals. This structure is based on the temporal sequencing previously described, where one UE (10) in each group transmits while the others perform measurement. In addition, since inter-group interference is kept at a minimum level, different groups can perform Sounding Reference Signals (SRS) transmission simultaneously. This simultaneity reduces the total measurement duration and enables more efficient use of system resources.

[0060] In Figure 3, how the CLI measurement process differs according to the grouping of the user equipment (UE) (10) in the network and the presence of the URLLC user equipment (URLLC UE) (60) is visually presented. According to Figure 3, based on the CLI measurement results by the network entity (20), the user equipment (UE) is dividedinto two separate groups: The first group (Group 1) is the one that includes a UE (60) with URLLC capability and active transmission. The second group (Group 2) consists only of standard UEs (10) and does not include any URLLC UE. Within the first group, in order to ensure timely and delay-free data transmission by the URLLC UE (60), the Sounding Reference Signal (SRS) transmissions and measurement activities of all other UEs in this group have been suspended. Thus, only the URLLC UE (60) remains active and directly proceeds to data transmission. This indicates that the system dynamically adapts to meet the low latency and high reliability requirements of URLLC services. Since the second group does not include any URLLC UE, the user equipment in this group continues the CLI measurement process using the time division multiplexing method. That is, while each UE (10) sequentially transmits an SRS, the other UEs in the same group perform CLI measurement using these signals. At the same time, since no significant interference is detected between different groups, these groups can perform measurements in parallel without affecting each other. This simultaneity both shortens the measurement time and enables more efficient use of system resources.

[0061] After the completion of this measurement process, the CLI values obtained by the UEs (10) within each group are analyzed. If the CLI value measured by a UE (10) exceeds a predefined aggressor reference value, that UE (10) is identified as an aggressor. That is, the system detects only those UEs (10) that cause high levels of interference and reports their identities to the network entity (20). In this way, the measurement data is simplified, and only the elements that directly affect network (30) performance are transmitted.

[0062] This method for measuring intra-cell inter-subband cross-link interference (CLI) is carried out jointly by the network entity (20) (e.g., base station, gNB, or central controller) and the user equipments (10) (UEs). In the implementation of the method, the network entity (20) assumes a central role; it is responsible for configuring the user equipments (10) to transmit Sounding Reference Signals (SRS), evaluating the reciprocity characteristic of the transmission channel, arranging the time-division multiplexing sequences, grouping the UEs (10) based on interference data, and prioritizing URLLC communications. The user equipments (10) (UEs) activelyparticipate in the process by triggering the CLI measurement procedure under certain conditions, transmitting Sounding Reference Signals (SRS), and performing interference measurements based on the received signals. Each UE (10) processes the measurement results and reports them to the network entity (20).

[0063] Furthermore, all of the process steps described above are executed by at least one processor included within both the network entity (20) and the user equipments (10) (UEs). These processors perform the operations within the scope of the method by executing software instructions stored in a memory. Since this processor-based architecture and software-controlled structure is a technically known and commonly used implementation in the field of communication systems, detailed hardware or software descriptions related to the relevant processors or software are not additionally provided in this document. Accordingly, the execution of the method steps is ensured through processors operating on the hardware and software components of the network entity (20) and the user equipments (10).

[0064] The above describes a flexible and scalable measurement method that enables high-precision and low-resource cross-link interference (CLI) measurement between user equipment (10) in SBFD systems. Thanks to its two-step structure, the method first performs a low-time-cost, wide-scope scanning in the first step to preliminarily identify potential aggressor UEs (50), and then, in the second step, confirms this preliminary identification with high accuracy through narrowband time division multiplexing full bandwidth measurements. In this way, both processing efficiency and measurement accuracy are achieved in interference characterization. Thus, measurement duration and time-frequency resource usage are minimized. Activating network (30) resources only when necessary increases the overall spectral efficiency of the system, improves interference-sensitive user experience, and also reduces energy consumption across the network (30). The prioritization mechanism developed specifically for URLLC users adapts the CLI measurement process to the critical service needs of these users, ensuring the continuity of low-latency and high-reliability communication. In addition, through flexible reporting and dynamic grouping, the system can maintain control even in high-density UE (10) scenarios and can adapt itself to complex network (30) conditions.The scope of protection of the invention is specified in the attached claims and cannot be limited to those explained for sampling purposes in this detailed description. It is evident that a person skilled in the art may exhibit similar embodiments in light of the above-mentioned facts without drifting apart from the main theme of the invention.

Claims

CLAIMS1. A method for measuring intra-cell inter-subband cross-link interference (CLI) occurring between user equipment (10) (UEs) in Subband Full-Duplex (SBFD) networks (30) characterized in that it comprises the steps of- configuring the UEs (10) by the network entity (20) to transmit Sounding Reference Signal (SRS) using frequency / code division multiplexing,- evaluating whether the transmission channel exhibits reciprocity characteristics,- in case it is determined that the transmission channel does not exhibit reciprocity characteristics, performing CLI measurements among the UEs (10) in the network (30) using a binary splitting method,- reporting the CLI measurements to the network entity (20),- grouping all UEs (10) in the network (30) by the network entity (20) in such a manner that UEs (10) with interference values close to each other within a reference value range are placed in the same group,- configuring full bandwidth time-division multiplexing Sounding Reference Signal (SRS) transmissions in each group such that only one UE (10) transmits and the others measure interference,- determining whether there exists a URLLC user equipment (60) (URLLC UE) with a pending transmission in the network (30);- in case it is determined that no URLLC UE (60) is present in the network (30), identifying the CLI values of the UEs (10) within each group;- reporting to the network entity (20) those UEs (10) in the group whose CLI values exceed an aggressor reference value.

2. The method according to claim 1 , is characterized in that the method further comprises the step of configuring the UEs (10) by the network entity (20) to transmit Sounding Reference Signal (SRS) using frequency / code division multiplexing is performed as periodic, semi-persistent, or aperiodic.

3. The method according to claim 1 , is characterized in that the method further comprises that, in the step of performing CLI measurements using a binary splitting method among the UEs (10) in the network (30), in case it is determined that thetransmission channel does not exhibit reciprocity characteristics, the following substeps are followed to perform CLI measurement based on the binary splitting method:- calculating a total time interval according to the total number of UEs (40) in the network (30) and the number of sub-time intervals (t) constituting the total time interval,- dividing each of the sub-time intervals (t) into a first time interval (t1 ) and a second time interval (t2),- dividing the UEs (10) grouped together into a first UE (10) group and a second UE (10) group, at the initial time (tO) of each sub-time interval (t),- transmitting the Sounding Reference Signal (SRS) by the first UE (10) group and measuring the interference values of the UEs (10) in the second UE (10) group based on the SRS received from the first UE (10) group, in the first time interval (t1) of the sub-time interval (t),- transmitting the Sounding Reference Signal (SRS) by the second UE (10) group and measuring the interference values of the UEs (10) in the first UE (10) group based on the SRS received from the second UE (10) group, in the second time interval (t2) of the sub-time interval (t),- obtaining the interference measurements of all UEs (10) in the network (30) by repeating the above steps for the number of sub-time intervals (t).

4. The method according to claim 1 , is characterized in that the method further comprises that in case the transmission channel is determined to exhibit reciprocity characteristics after evaluating whether it exhibits reciprocity characteristics, performing the CLI measurement using a reciprocity-based method.

5. The method according to claim 4, is characterized in that the method further comprises that, in the step of performing CLI measurement using a reciprocitybased method, in case the transmission channel is determined to exhibit reciprocity characteristics, the following sub-steps are followed to perform CLI measurement based on the reciprocity method:- calculating a total time interval according to the total number of UEs (40) in the network (30) and the number of sub-time intervals (t) constituting the total time interval,- dividing each of the sub-time intervals (t) into a first time interval (t1) and a second time interval (t2),- dividing the active UEs (10) into a first UE (10) group and a second UE (10) group, at the initial time (tO) of each sub-time interval (t),- transmitting the Sounding Reference Signal (SRS) by the first UE (10) group and measuring the CLI values of the UEs (10) in the second UE (10) group according to the SRS received from the first UE (10) group, in the first time interval (t1),- estimating the CLI values of the UEs (10) in the first UE (10) group by inference, based on the signals received by the UEs (10) in the second UE (10) group during the first time interval (t1), in the second time interval (t2), - obtaining the interference measurements of all UEs (10) in the network (30) by repeating the above steps for the number of sub-time intervals (t).

6. The method according to claim 1 , is characterized in that the method further comprises that in the step of reporting the CLI measurements to the network entity (20), the following sub-steps are followed to perform the reporting:- collecting the CLI measurements by the receiving UEs (10),- generating the reports by organizing the collected CLI measurements either as CLI matrices or as a limited data set including the identities of aggressor UEs (50) whose values exceed an aggressor reference value.

7. The method according to claim 1 , is characterized in that the method further comprises that in the step of grouping all UEs (10) in the network (30) by the network entity (20) such that UEs (10) with interference values close to each other within a reference value range are placed in the same group, location-based information or relative signal characteristics information can also be used.

8. The method according to claim 1 , is characterized in that the method further comprises the step of prioritizing the URLLC transmission by disabling SoundingReference Signal (SRS) transmission for all UEs (10) in the group in which a URLLC UE (60) is determined to be present in the network (30).

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