Cell control device and cell control method performed by same

Abstract

The present invention provides specific cell control technology whereby an optimal cell shape (and tilt) can be reselected / applied adaptively to adjacent cells and dynamic environmental changes in operation in a multi-cell environment in which different cell shapes are mixed / used.

Description

CELL control device and CELL control method performed in the device

[0001] The present invention relates to Open RAN (Radio Access Network, O-RAN) technology.

[0002] This application claims the benefit of Korean Application No. 10-2024-0119166, filed September 3, 2024, the entire contents of which are incorporated herein by reference for all purposes.

[0003] In a mobile network that provides mobile communications services, the RAN (Radio Access Network) supports wireless connection between terminals and the network.

[0004] With the advent of 5G, the need for increased wireless speeds, increased fronthaul capacity due to the introduction of MIMO, and additional infrastructure expansion such as optical lines has increased, leading to increased base station installation and operating costs for communication service operators. To address this, Open RAN (Radio Access Network, O-RAN) technology has emerged.

[0005] Simply put, O-RAN is a technology that standardizes the interface that connects the equipment required to implement base station devices so that they can be interconnected. Based on O-RAN, it enables interoperability between RUs (Radio Units, hereinafter O-RUs) and DUs (Distributed Units, hereinafter O-DUs) from different manufacturers / vendors.

[0006] In an O-RAN system based on O-RAN, each piece of equipment developed by different manufacturers / vendors, namely CU (Centralized Unit, hereinafter referred to as O-CU), O-DU, O-RU, and an intelligent base station control device (e.g. SMO, RIC, etc.) for controlling the base station device (O-CU / O-DU / O-RU) composed of these pieces of equipment, has a structure in which the equipment operates in conjunction with each other.

[0007] Meanwhile, in the O-RAN standard, there is no separate specification for the Cell Shape to be used in O-RU.

[0008] For this reason, in the O-RAN system, since each base station device's cell interoperates / operates with heterogeneous (multi-vendor) O-RU equipment developed by different manufacturers / vendors, different cell shapes are used in multiple overlapping / mixed cells.

[0009] Due to this, in the existing O-RAN system, in a multi-cell environment where multiple cells overlap / mix, there is a problem that network optimization is difficult because different cell shapes are being used in a mixed manner without knowing which cell shape is being used between adjacent cells.

[0010] The problem to be solved in the present invention is to propose a new cell control technology that can apply an optimal cell shape (and tilt) by considering a multi-cell environment in which different cell shapes are mixed / used in a heterogeneous (multi-vendor) equipment (O-RU) based O-RAN system.

[0011] A cell control device according to one embodiment of the present invention comprises: a memory including a command; and a processor that, by executing the command, specifies an adjacent cell to be reflected when a cell of a serving cell is changed based on collected information collected for the cell, and re-selects at least one of a cell shape and a tilt for the serving cell by reflecting the cell shape of the specific adjacent cell.

[0012] Specifically, the adjacent Cell to be reflected can be specified as a Cell belonging to the adjacent Cell reflection area size based on the serving Cell, based on the adjacent Cell reflection area size set for the Cell change of the serving Cell, based on the construction information of each Cell in the collected information.

[0013] Specifically, the Cell shape of the specific adjacent Cell may be composed of a plurality of 3D Bins created by dividing the 3D space serviceable by the specific adjacent Cell into preset unit lengths based on the construction information and supportable Cell Shape information of each Cell in the collected information.

[0014] Specifically, the serving Cell and the adjacent Cell are formed by an RU (Radio Unit, O-RU) supporting Open RAN (Radio Access Network, O-RAN), and the processor, when the Cell of the serving Cell is changed, transmits information on the re-selected Cell Shape and Tilt for the serving Cell or the serving Cell and the adjacent Cell to the O-RU of the serving Cell or the serving Cell and the adjacent Cell, so that the information can be applied to the serving Cell or the serving Cell and the adjacent Cell.

[0015] Specifically, the processor calculates the reception signal strength of the serving Cell received in each of the plurality of 3D Bins for each combination of Cell Shape and Tilt that can be supported by the serving Cell, determines a Bin in which the calculated reception signal strength is greater than or equal to a preset threshold as a Coverage In Bin, and re-selects a combination of the Cell Shape and Tilt among the combinations of the Cell Shape and Tilt that is determined to be the Coverage In Bin and has the largest number of Bins in which a UE exists as a Cell Shape and Tilt for expanding the Coverage of the serving Cell.

[0016] Specifically, the processor calculates the reception signal strength of the serving cell and the adjacent cell received in each of the plurality of 3D bins for each combination of Cell Shape and Tilt that can be supported by the serving cell and the adjacent cell, determines a bin in which the difference between the strongest reception signal strength and the next strongest reception signal strength among the plurality of 3D bins is less than a preset threshold difference as an overlapping bin, and re-selects a combination of the Cell Shape and Tilt among the combinations of the Cell Shape and Tilt that is determined to be the overlapping bin and has the smallest number of bins in which a UE exists as a Cell Shape and Tilt for mitigating interference between the serving cell and the adjacent cell.

[0017] Specifically, the processor calculates the reception signal strength of the serving cell and the adjacent cell received in each of the plurality of 3D bins for each combination of Cell Shape and Tilt that can be supported by the serving cell and the adjacent cell, determines a bin in which the difference between the strongest reception signal strength and the next strongest reception signal strength among the plurality of 3D bins is less than a preset threshold difference as an overlapping bin, and re-selects a combination having the smallest sum of weights assigned according to the number of UEs present in each bin among the combinations of Cell Shape and Tilt for load balancing of the serving cell and the adjacent cell.

[0018] A cell control method performed in a cell control device according to one embodiment of the present invention comprises the steps of: specifying an adjacent cell to be reflected in a cell change of a serving cell based on collected information about the cell; and, when the cell of the serving cell is changed, at least one of a cell shape and a tilt for the serving cell can be re-selected by reflecting the cell shape of the specific adjacent cell.

[0019] Specifically, the Cell shape of the specific adjacent Cell may be composed of a plurality of 3D Bins created by dividing the 3D space serviceable by the specific adjacent Cell into preset unit lengths based on the construction information and supportable Cell Shape information of each Cell in the collected information.

[0020] Specifically, the re-selection step may include, for each combination of Cell Shape and Tilt that can be supported by the serving Cell and the adjacent Cell, using the received signal strength from the serving Cell and the adjacent Cell received in each of the plurality of 3D Bins and a weight assigned according to the number of UEs present in each Bin, checking at least one condition among coverage expansion of the serving Cell, interference mitigation between the serving Cell and the adjacent Cell, and load balancing, and re-selecting a combination that satisfies the checked condition among the combinations of Cell Shape and Tilt as the Cell Shape and Tilt of the serving Cell and the adjacent Cell.

[0021] A computer program according to one embodiment of the present invention may be stored in a medium to execute a step of specifying an adjacent cell to be reflected in a cell change of a serving cell based on collected information collected about the cell, in combination with hardware of a cell control device, and a step of re-selecting at least one of a cell shape and a tilt for the serving cell by reflecting the cell shape of the specific adjacent cell when the cell of the serving cell is changed.

[0022] According to embodiments of the present invention, in an O-RAN system based on heterogeneous (multi-vendor) equipment (O-RU), a specific cell control technology configuration is realized that can adaptively apply an optimal cell shape (and tilt) by considering a multi-cell environment in which different cell shapes are mixed / used.

[0023] Accordingly, according to the present invention, even in a multi-cell environment where different cell shapes are mixed / used in an O-RAN system, the optimal cell shape (and tilt) that adaptively responds to dynamic environmental changes during operation is applied, thereby optimizing the overall network performance through coverage hole improvement, interference mitigation, load balancing, etc.

[0024] Figure 1 is an example diagram showing the O-RAN system structure.

[0025] FIG. 2 is a block diagram showing the configuration of a cell control device according to one embodiment of the present invention.

[0026] Figure 3 is an example diagram of configuring the cell shape of adjacent cells to be reflected in the present invention into a three-dimensional bin.

[0027] Figures 4 to 6 are flowcharts showing examples of call flows in which the cell control method of the present invention operates.

[0028] Hereinafter, various embodiments of the present invention will be described with reference to the attached drawings.

[0029] The present invention relates to Open RAN (Radio Access Network, O-RAN) technology.

[0030] In a mobile network that provides mobile communications services, the RAN (Radio Access Network) supports wireless connection between terminals and the network.

[0031] With the advent of 5G, the need for increased wireless speeds, increased fronthaul capacity due to the introduction of MIMO, and additional infrastructure expansion such as optical lines has increased, leading to increased base station installation and operating costs for communication service operators. To address this, Open RAN (Radio Access Network, O-RAN) technology has emerged.

[0032] Simply put, O-RAN is a technology that standardizes the interface that connects the equipment required to implement base station devices so that they can be interconnected. Based on O-RAN, it enables interoperability between RUs (Radio Units, hereinafter O-RUs) and DUs (Distributed Units, hereinafter O-DUs) from different manufacturers / vendors.

[0033] In an O-RAN system based on O-RAN, each piece of equipment developed by different manufacturers / vendors, namely CU (Centralized Unit, hereinafter referred to as O-CU), O-DU, O-RU, and an intelligent base station control device (e.g. SMO, RIC, etc.) for controlling the base station device (O-CU / O-DU / O-RU) composed of these pieces of equipment, has a structure in which the equipment operates in conjunction with each other.

[0034] Figure 1 shows the structure of the O-RAN system.

[0035] As can be seen in Figure 1, the O-RAN system is designed to have a structure for implementing an open and intelligent radio access network.

[0036] These O-RAN systems can be broadly divided into base station equipment implemented separately as O-CU, O-DU, and O-RU equipment, and intelligent base station control equipment (e.g., SMO, RIC, etc.) for controlling base station equipment.

[0037] In brief, intelligent base station control devices can be defined as Service Management and Orchestration Framework (SMO) and RAN Intelligent Controller (RIC).

[0038] In particular, the RIC corresponding to the controller for the intelligent wireless access network can be divided into a Non-Real Time RIC (> 1 second) layer and a Near-Real Time RIC (0.01 second to 1 second) layer based on control latency.

[0039] The Non-Real Time RIC layer performs big data analysis and artificial intelligence-based management through machine learning, including RAN policy management, network traffic patterns, terminal mobility patterns, service types, and quality of service (QoS) prediction patterns.

[0040] The trained model generated in the Non-Real Time RIC is distributed to the Near-Real Time RIC through the A1 interface.

[0041] The Near-Real Time (RIC) layer provides near-real-time radio resource management capabilities. It handles functions such as terminal-level load balancing, resource block management, quality of service (QoS), and terminal mobility management.

[0042] The Near-Real-Time RIC layer transmits control commands (e.g., handovers, resource allocation, etc.) to the O-CU and O-DU via the E2 interface and collects measured data, providing it to the Non-Real-Time RIC. This interaction optimizes control algorithms related to load balancing, mobility management, and other aspects.

[0043] The O-CU is divided into a control plane (O-CU-CP) that conveys control information and a user plane (O-CU-UP) that conveys traffic, and executes control commands received from the Near-Real Time RIC. The O-CU supports the F1 / W1 / E1 / X2 / Xn interfaces defined in the 3GPP standard.

[0044] O-DU is responsible for real-time L2 (Layer 2) functions of the Radio Link Control and Medium Access Control layers and baseband signal processing.

[0045] O-RU performs radio signal processing.

[0046] An open fronthaul interface is defined between the O-DU and O-RU.

[0047] As illustrated in Figure 1, the O-RAN system has a structure in which equipment such as O-CU, O-DU, O-RU, SMO, and RIC developed from different manufacturers / vendors operate in conjunction with each other.

[0048] Meanwhile, in the current O-RAN standard, there is no separate specification for the Cell Shape to be used in O-RU.

[0049] For this reason, in the O-RAN system, since each base station device's cell interoperates / operates with heterogeneous (multi-vendor) O-RU equipment developed by different manufacturers / vendors, different cell shapes are used in multiple overlapping / mixed cells.

[0050] In this regard, although an O-DU can query and control the Cell Shape information supported by the O-RU it is connected to, it is limited to the O-RUs connected to the same O-DU, and it is impossible to know which Cell Shape is being used by the O-RU / Cell of another adjacent O-DU due to the lack of standards for information transmission / sharing.

[0051] Since the cell shape is involved in the call connection and mobility of the terminal (UE), in order to optimize the performance of the overall network, it is necessary to apply the optimal cell shape (and tilt) that takes into account the multi-cell environment in terms of coverage, inter-cell interference, and load balancing operation. However, due to the lack of tactical standards, it is impossible to apply the optimal cell shape (and tilt) that takes into account the multi-cell environment.

[0052] In this way, in the existing O-RAN system, in a multi-cell environment where multiple cells overlap / mix, there is a problem that network optimization is difficult because different cell shapes are being used in a mixed manner in a situation where it is not possible to know which cell shape is being used between adjacent cells.

[0053] Accordingly, in the present invention, in a heterogeneous (multi-vendor) equipment (O-RU) based O-RAN system, a specific technical configuration is intended to be realized that can apply an optimal cell shape (and tilt) that adaptively responds to dynamic environmental changes (e.g., cell add / delete, UE and traffic load changes, etc.) in consideration of a multi-cell environment in which different cell shapes are mixed / used.

[0054] FIG. 2 shows the configuration of a cell control device (100) that implements the specific technology proposed in the present invention, that is, the cell control method.

[0055] Before a specific description, the Cell control device (100) of the present invention is a device that controls a Cell formed by an O-RU in an O-RAN system, and may be an O-RAN Cell control device, and as an example, may be implemented in an intelligent base station control device (e.g., SMO, RIC, etc.).

[0056] In addition, in FIG. 2, one base station device (70) of the present invention under the control of the O-RAN Cell control device (100) is illustrated, but this is only for convenience of explanation and diagram, and multiple base station devices (70) may exist.

[0057] In addition, in FIG. 2, one wireless module (10, O-RU) connected to a base station module (50, O-CU / O-DU) in a base station device (70) is illustrated, but this is only for convenience of explanation and diagram, and multiple O-RUs (10) may exist.

[0058] However, in the following detailed description, for the sake of convenience of explanation, the description will be based on a situation in which one Cell is formed through the O-RU (10) constituting the base station device (70) as illustrated in FIG. 2, and the description will be made assuming a situation in which other O-RUs / Cells of adjacent base station devices (70) are mixed around this Cell (hereinafter, serving Cell (10)).

[0059] Specifically, an O-RAN Cell control device (100) according to an embodiment of the present invention may be configured with a memory (not shown) including a command, a processor (hereinafter, control unit (120)) that executes the command, and, based on collected information about the Cell, specifies an adjacent Cell to be reflected when the Cell of the serving Cell (10) is changed, and reflects the Cell shape of the specific adjacent Cell to re-select at least one of Cell Shape and Tilt for the serving Cell (10).

[0060] In particular, the present invention proposes a structure for managing the profile information (Cell Shape information, Cell ID, manufacturer name, equipment model name, etc.) of each cell by adding a 'Cell Shape Repository', which is not present in the O-RAN Architecture of the current O-RAN standard, to the SMO / RIC framework.

[0061] Accordingly, the present invention proposes a technical configuration in which an O-RAN Cell control device (100, e.g., SMO / RIC) existing in a centralized location can optimize Cell shape and Tilt for multiple Cells using different Cell Shapes by using a 'Cell Shape Repository'.

[0062] In relation to this, as illustrated in FIG. 2, an O-RAN Cell control device (100, e.g., SMO / RIC) according to an embodiment of the present invention includes a collection / management unit (110) that manages collected information collected for a cell, and the collection / management unit (110) can be divided into a Cell Shape Repository (113) and a Cell Database (116) depending on the type of information to be managed.

[0063] The Cell Shape Repository (113) stores / manages the profile information of each cell (cell shape information, cell ID, manufacturer name, equipment model name, etc.).

[0064] Specifically, to explain an embodiment, according to the present invention, each O-RU (10) can transmit / upload information on the Cell ID, manufacturer name, equipment model name, and supportable Cell Shape that it forms, directly or through an O-DU (53) that is linked to it.

[0065] At this time, according to the present invention, each O-RU (10) can transmit / upload the aforementioned Cell ID, manufacturer name, equipment model name, and supportable Cell Shape information to the O-RAN Cell control device (100, particularly Cell Shape Repository (113)) of the present invention at the time of Initial Setup, or at each preset period, or when a preset event occurs (e.g., Cell Add / Delete occurs, etc.).

[0066] Accordingly, in the Cell Shape Repository (113), the profile information of each cell (Cell Shape information and Cell ID, manufacturer name, equipment model name, etc.) can be stored / managed.

[0067] More specifically, for example, in the Cell Shape Repository (113), Cell Shape information that can be supported based on the manufacturer / equipment model name can be stored from the information transmitted / uploaded.

[0068] The Cell Database (116) serves to store / manage construction information (e.g., latitude and longitude, height, azimuth, elevation, etc.) and geographical UE distribution information for each cell.

[0069] To explain a specific example, in the Cell Database (116), construction information including latitude / longitude / height, azimuth / elevation tilt, etc. determined at the time of construction of each Cell (Cell ID) can be stored. Of course, if the construction status of a Cell changes, the construction information of the Cell will also be changed / updated and stored / managed.

[0070] In addition, in the Cell Database (116), geographical UE distribution information related to the number of UEs and / or traffic volume accommodated by each Cell (Cell ID) can be stored.

[0071] For example, according to the present invention, each O-RU (10) can collect geographic UE distribution information in the cell it forms in real time, directly or through an O-DU (53) connected to it, at preset intervals or when a preset event occurs (e.g., Cell Shape / Tilt change, etc.), and transmit / upload it to the O-RAN Cell control device (100, particularly Cell Database (116)) of the present invention.

[0072] Meanwhile, FIG. 2 illustrates a structure in which a Cell Shape Repository (113) and a Cell Database (116) are included in an O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention, but this is only an example.

[0073] That is, the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention will have no restrictions on its implementation structure as long as it can be linked with the Cell Shape Repository (113) and the Cell Database (116).

[0074] Accordingly, the present invention may also be applied to a structure in which at least one of the Cell Shape Repository (113) and the Cell Database (116) is implemented in a device / node separate from the O-RAN Cell control device (100, e.g., SMO / RIC).

[0075] The control unit (120) can perform cell control to optimize the cell shape and tilt of a cell (serving cell, and further, adjacent cell) by re-selecting and applying the cell shape and tilt to a serving cell (hereinafter, described as a cell (10) by an O-RU (10)) that is determined to require cell change (hereinafter, cell optimization) among the cells managed by the O-RAN cell control device (100, e.g., SMO / RIC).

[0076] At this time, according to an example, the control unit (120) can determine that a cell that has information transmission / upload to the Cell Shape Repository (113) is a serving cell (10) that requires cell optimization.

[0077] Or, according to another example, the control unit (120) may determine a Cell that has a report of a separately defined Event (e.g., occurrence of Cell Add / Delete, occurrence of deterioration above threshold in the KPI / interference level / traffic load being monitored, operator request, etc.) as a serving Cell (10) that requires Cell optimization.

[0078] Below, in the present invention, a cell control process for optimizing the cell shape / tilt of a cell (a serving cell, and further, an adjacent cell) will be specifically described.

[0079] The control unit (120) specifies an adjacent cell to be reflected in the cell change of the serving cell (10), i.e., cell optimization, based on the collected information about the cell, i.e., the cell shape repository (113) and the cell database (116).

[0080] Here, the adjacent cell to reflect the cell optimization of the serving cell (10) can be specified as a cell belonging to the adjacent cell reflection area size set for the cell change / optimization of the serving cell (10) based on the construction information of each cell in the collected information of the tactics, based on the adjacent cell reflection area size set for the cell change / optimization of the serving cell (10).

[0081] For example, in the present invention, with respect to cell control that optimizes cell shape and tilt, a policy can be preset by the operator, and such policy can include an intent for optimization (e.g., coverage expansion, interference mitigation, load balancing, etc.) and a size of an adjacent cell reflection area (e.g., XX km, etc.).

[0082] Accordingly, when the control unit (120) determines / confirms the serving Cell (10) that requires Cell optimization, it can confirm the Cell belonging to the adjacent Cell reflection area size (e.g., XX km, etc.) according to the policy based on the collected information, particularly the construction information in the Cell Database (116), and can specify the Cell confirmed in this way as the "adjacent Cell to which the Cell optimization of the serving Cell (10) will be reflected."

[0083] And, the control unit (120) can optimize the Cell Shape / Tilt by re-selecting and applying the Cell Shape and Tilt for the serving Cell (10) and further the Cell Shape and Tilt for a specific adjacent Cell, reflecting the Cell Shape of a specific adjacent Cell as described above.

[0084] At this time, the cell shape of a specific adjacent cell can be composed of a number of 3D bins created by dividing the 3D space that can be serviced by the specific adjacent cell into preset unit lengths based on the construction information and supportable cell shape information of each cell in the tactical collection information.

[0085] In relation to this, Fig. 3 illustrates an example of configuring the cell shape of adjacent cells to be reflected in the present invention into a three-dimensional bin.

[0086] As illustrated in FIG. 3, in the present invention, based on the construction information of the serving Cell (10), a serviceable three-dimensional space of another Cell (a specific adjacent Cell) belonging to the adjacent Cell reflection area size (e.g., XX km, etc.) can be configured into a number of three-dimensional Bins (e.g., Bin 1 to Bin 1000) divided by unit length.

[0087] Accordingly, the control unit (120) can configure and reflect the cell shapes of adjacent cells, i.e., multiple 3D Bins, to be reflected in the cell shape / tilt optimization as shown in FIG. 3, thereby performing cell shape / tilt optimization according to the intent for optimization (e.g., coverage expansion, interference mitigation, load balancing).

[0088] To explain an embodiment more specifically, the function of performing Cell Shape / Tilt optimization of the present invention can be implemented in a separate application (hereinafter, operation App (125)) within an O-RAN Cell control device (100, e.g., SMO / RIC).

[0089] According to this embodiment, when the control unit (120) determines / confirms a serving Cell (10) requiring Cell optimization, it can request Cell Shape / Tilt optimization while transmitting the Cell ID of the serving Cell (10), an Intent for optimization according to policy (e.g., coverage expansion, interference mitigation, load balancing, etc.), and the size of the adjacent Cell reflection area (e.g., XX km, etc.) to the operation App (125).

[0090] The operation App (125) receiving such a Cell Shape / Tilt optimization request can obtain (request / response) the construction information and geographical UE distribution information of the serving Cell (10) from the Cell Database (116) using the Cell ID and adjacent Cell reflection area size (e.g., XX km, etc.) of the serving Cell (10), and the Cell ID, construction information, and geographical UE distribution information of another Cell (a specific adjacent Cell) belonging to the adjacent Cell reflection area size (e.g., XX km, etc.) based on the serving Cell (10).

[0091] Thereafter, the operation App (125) can obtain (request / response) Cell Shape information of the serving Cell (10) and each of the specific adjacent Cells from the Cell Shape Repository (113) using the Cell ID of the serving Cell (10) and the Cell ID of the specific adjacent Cell.

[0092] After acquiring the necessary information in this way, the operation App (125) configures a number of 3D Bins, i.e., “cell shapes of adjacent cells” to be reflected in Cell Shape / Tilt optimization, as shown in Fig. 3.

[0093] In addition, the operation App (125) can perform Cell Shape / Tilt optimization according to the Intent (e.g., coverage expansion, interference mitigation, load balancing, etc.) received when requesting Cell Shape / Tilt optimization by reflecting a plurality of 3D Bins.

[0094] At this time, the unit length (e.g., 10 m) of width / length / height that constitutes a plurality of 3D Bins (e.g., 10 m X 10 m X 10 m) can be determined according to the operation / calculation performance of the operation App (125), and the better the operation / calculation performance of the operation App (125), the shorter the unit length can be, and the shorter this unit length, the better the Cell Shape / Tilt optimization performance described later will be.

[0095] Below, we will describe an embodiment in which coverage expansion is set as an intent for optimization.

[0096] The control unit (120, particularly the operation App (125)) calculates the reception signal strength (SS-RSRP, dBm) of the serving cell (10) and the reception signal strength (SS-RSRP, dBm) of each adjacent cell, which are received in each of the plurality of 3D bins configured in advance, for each combination of cell shapes and tilts that can be supported by the serving cell (10) and the adjacent cell.

[0097] Specifically, the control unit (120, particularly the operation App (125)) calculates the distance from the serving Cell (10) and each of the adjacent Cells to the center of each of the three-dimensional Bins based on the construction information of the serving Cell (10) and each of the adjacent Cells, and can calculate the azimuth angle and the elevation angle from the serving Cell (10) and each of the adjacent Cells to the center of each of the three-dimensional Bins.

[0098] Accordingly, the control unit (120, particularly the operation App (125)) can obtain beam gain information for each previously calculated Azimuth / Elevation angle for each combination of supportable Cell shape and Tilt of each Cell (serving Cell (10), adjacent Cell) from the Cell Shape Repository (113) and can calculate Pathloss up to each Bin.

[0099] Accordingly, the control unit (120, particularly the operation App (125)) can calculate the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) and the adjacent Cell received in each Bin # for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell according to the following mathematical expression 1.

[0100]

[0101] Meanwhile, the control unit (120, particularly the operation App (125)) can check the geographical UE distribution information of each cell from the Cell Database (116), and can assign a weight according to the number of UEs present in each of the plurality of 3-dimensional Bins configured in advance.

[0102] For example, if there are no UEs in the bin, a weight of 0 can be assigned, and as the number of UEs in the bin increases, a weight closer to 1 can be assigned.

[0103] When coverage expansion is set as an intent for optimization, the control unit (120, particularly the operation App (125)) determines that a bin in which the received signal strength (SS-RSRP, dBm) of the serving cell (10) calculated for each bin is greater than a preset threshold for each combination of cell shape and tilt that can be supported by the serving cell (10) is a Coverage In Bin.

[0104] That is, in the present invention, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10), the Cell shape (multiple Bins) of the adjacent Cell is reflected to determine and find a portion (Coverage In Bin) of the adjacent Cell in which the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) is significantly large (≥threshold).

[0105] Accordingly, the control unit (120, particularly the operation App (125)) can re-select, among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10), the combination that is determined to be a Coverage In Bin and has the largest number of Bins (weight!= 0) in which the UE exists, as the Cell Shape and Tilt for coverage expansion of the serving Cell (10).

[0106] The control unit (120) can perform Cell Shape / Tilt optimization for the serving Cell (10) by transmitting the Cell Shape and Tilt values ​​of the combination re-selected for coverage expansion of the serving Cell (10) to the O-RU (10) of the serving Cell (10) and applying them.

[0107] Next, we will describe an embodiment in which interference mitigation is set as an intent for optimization.

[0108] As described above, the control unit (120, particularly the operation App (125)) can calculate the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) and the adjacent Cell for each Bin, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell.

[0109] Accordingly, the control unit (120, especially the operation App (125)) determines the strongest reception signal intensity (1) among a number of 3-dimensional bins. STHighest SS-RSRP) and next highest received signal strength (2 nd A bin whose difference between the highest SS-RSRP is less than a preset threshold is considered to be an overlapping bin.

[0110] That is, in the present invention, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell, the Cell shape (multiple Bins) of the adjacent Cell is reflected so that the difference between the received signal strength (SS-RSRP, dBm) between the Cells is not large ( <threshold) 인접 Cell의 일부분(중첩 Bin)을 판단하여 찾을 수 있다.

[0111] Accordingly, the control unit (120, particularly the operation App (125)) may re-select, among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell, a combination that is judged to be an overlapping Bin and has the smallest number of Bins (weight!= 0) in which the UE exists, as the Cell Shape and Tilt for mitigating interference between the serving Cell (10) and the adjacent Cell.

[0112] The control unit (120) can perform Cell Shape / Tilt optimization for the serving Cell (10) and the adjacent Cell by transmitting and applying the Cell Shape and Tilt values ​​of the combination re-selected for interference mitigation to each O-RU (10) of the serving Cell (10) and the adjacent Cell.

[0113] Next, we will describe an example where load balancing is set as an intent for optimization.

[0114] As described above, the control unit (120, particularly the operation App (125)) can calculate the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) and the adjacent Cell for each Bin, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell.

[0115] Accordingly, the control unit (120, especially the operation App (125)) determines the strongest reception signal intensity (1) among a number of 3-dimensional bins. ST Highest SS-RSRP) and next highest received signal strength (2 nd A bin whose difference between the highest SS-RSRP is less than a preset threshold is considered to be an overlapping bin.

[0116] And the control unit (120, particularly the operation App (125)) can re-select, among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell, the combination with the smallest sum of weights assigned to each Bin judged to be an overlapping Bin, as the Cell Shape and Tilt for load balancing of the serving Cell (10) and the adjacent Cell.

[0117] That is, in the present invention, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell, the Cell shape (multiple Bins) of the adjacent Cell is reflected so that the difference between the received signal strength (SS-RSRP, dBm) between the Cells is not large ( <threshold) 인접 Cell의 일부분(중첩 Bin)을 판단하되, Load balancing의 영향에 실시간으로 놓이게 될 UE가 가능한 적은 조합을 찾을 수 있다.

[0118] The control unit (120) can perform Cell Shape / Tilt optimization for the serving Cell (10) and adjacent Cell by transmitting the Cell Shape and Tilt values ​​of the combination re-selected for load balancing to each O-RU (10) of the serving Cell (10) and adjacent Cell so that they are applied.

[0119] As can be seen from the above description, according to the present invention, a specific Cell control technology configuration is realized that adaptively re-selects the optimal Cell Shape (and Tilt) that matches the operator's intent (e.g., coverage expansion, interference mitigation, load balancing) by reflecting the construction information of each Cell, information on Cell Shapes that can be supported, and dynamic environmental changes (e.g., Cell Add / Delete, UE and Traffic load changes, etc.).

[0120] In particular, the present invention realizes a new cell control technology configuration that adaptively re-selects the optimal cell shape (and tilt) by reflecting the subdivided adjacent cell shape (multiple 3D bins) specified by the serving cell and adjacent cell reflection area size, rather than considering only the serving cell.

[0121] Accordingly, according to the present invention, even in a multi-cell environment where different cell shapes are mixed / used in an O-RAN system, the optimal cell shape (and tilt) can be re-selected / applied to adaptively respond to dynamic environmental changes during operation, thereby having the effect of optimizing overall network performance through coverage hole improvement, interference mitigation, load balancing, etc.

[0122] Hereinafter, with reference to FIGS. 4 and 6, examples of call flows in which the cell control method of the present invention operates will be described.

[0123] In the following description, for convenience of explanation, the contents illustrated in the aforementioned Figure 2 will be described. In addition, in the following description, the Cell control device (100, hereinafter referred to as the O-RAN Cell control device) will be mentioned as an operating entity in which the Cell control method of the present invention operates.

[0124] First, referring to FIG. 4, a configuration for collecting and managing information for each cell in the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention will be described.

[0125] As illustrated in FIG. 4, according to the present invention, each O-RU (10) can transmit / upload information on the Cell ID, manufacturer name, equipment model name, and supportable Cell Shape that it forms, directly or through an O-DU (53) that is linked to it (S1).

[0126] Accordingly, the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention can store / manage the profile information (Cell Shape information and Cell ID, manufacturer name, equipment model name, etc.) of each Cell in the Cell Shape Repository (113) (S2).

[0127] Specifically, the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention can store / manage Cell Shape information that can be supported based on the manufacturer / equipment model name from information transmitted / uploaded to the Cell Shape Repository (113).

[0128] Meanwhile, the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention can store / manage Cell Database (116), construction information for each Cell (e.g., latitude / longitude, height, azimuth, elevation, etc.) and geographical UE distribution information (S4).

[0129] In this regard, according to the present invention, each O-RU (10) can collect geographic UE distribution information in the cell it forms in real time, directly or through an O-DU (53) linked to it, at preset intervals or when a preset event occurs (e.g., Cell Shape / Tilt change, etc.), and transmit / upload it to the O-RAN Cell control device (100, particularly Cell Database (116)) of the present invention (S3).

[0130] Referring to the following Figure 5, the process of optimizing Cell Shape / Tilt in the O-RAN Cell control device (100, e.g., SMO / RIC) of the present invention will be described in detail.

[0131] As illustrated in FIG. 4, the O-RAN Cell control device (100, particularly the control unit (120)) of the present invention can request Cell Shape / Tilt optimization to the operation App (125) for a serving Cell (hereinafter, described as Cell (10) by O-RU (10)) that is determined to require Cell change (hereinafter, Cell optimization) among the managed Cells (S5).

[0132] For example, when the control unit (120) determines / confirms a serving Cell (10) that requires Cell optimization, it can request Cell Shape / Tilt optimization while transmitting the Cell ID of the serving Cell (10), the Intent for optimization according to policy (e.g., coverage expansion, interference mitigation, load balancing, etc.), and the size of the adjacent Cell reflection area (e.g., XX km, etc.) to the operation App (125).

[0133] The O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can obtain (request / response) the construction information and geographical UE distribution information of the serving Cell (10) from the Cell Database (116) using the Cell ID and the adjacent Cell reflection area size (e.g., XX km, etc.) of the serving Cell (10), and the Cell ID, construction information, and geographical UE distribution information of another Cell (specific adjacent Cell) belonging to the adjacent Cell reflection area size (e.g., XX km, etc.) based on the serving Cell (10) (S6, S7).

[0134] Thereafter, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can obtain (request / response) Cell Shape information of the serving Cell (10) and each of the specific adjacent Cells from the Cell Shape Repository (113) using the Cell ID of the serving Cell (10) and the Cell ID of the specific adjacent Cell (S8, S9).

[0135] After acquiring the necessary information in this way, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention configures a "cell shape of adjacent cells", i.e., a plurality of 3-dimensional bins, to be reflected in the Cell Shape / Tilt optimization as shown in FIG. 3.

[0136] In addition, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can perform Cell Shape / Tilt optimization according to the Intent (e.g., coverage expansion, interference mitigation, load balancing, etc.) received in advance when requesting Cell Shape / Tilt optimization by reflecting a plurality of 3D Bins (S10).

[0137] Figure 6 illustrates an example of a detailed call flow for performing Cell Shape / Tilt optimization when coverage expansion, interference mitigation, and load balancing are set as intents for optimization.

[0138] Referring to FIG. 6, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention calculates the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) and the reception signal strength (SS-RSRP, dBm) of each adjacent Cell, which are received in each of the plurality of 3D Bins configured in advance, for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell (S11).

[0139] Specifically, the operation App (125) can calculate the distance, azimuth angle, and elevation angle from the serving Cell (10) and each adjacent Cell to the Bin center for each 3D Bin based on the construction information of each serving Cell (10) and each adjacent Cell.

[0140] Accordingly, the operation App (125) can obtain beam gain information for each previously calculated Azimuth / Elevation angle for each combination of supportable Cell shape and Tilt of each Cell (serving Cell (10), adjacent Cell) from the Cell Shape Repository (113) and can calculate Pathloss up to each Bin.

[0141] Accordingly, the operation App (125) can calculate the reception signal strength (SS-RSRP, dBm) of the serving Cell (10) and the adjacent Cell received in each Bin # for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell according to the aforementioned mathematical expression 1 (S11).

[0142] And the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can check the geographical UE distribution information of each cell from the Cell Database (116), and can assign a weight according to the number of UEs present in each of the plurality of 3-dimensional Bins configured in advance (S12).

[0143] For example, if there are no UEs in the bin, a weight of 0 can be assigned, and as the number of UEs in the bin increases, a weight closer to 1 can be assigned.

[0144] The O-RAN Cell control device (100, particularly the operation App (125)) of the present invention, when coverage expansion is set as an intent for optimization (S13 Yes), classifies a Coverage In Bin (weight!= 0) in which a UE exists and the received signal strength (SS-RSRP, dBm) of the serving Cell (10) calculated for each Bin in advance is equal to or greater than a preset threshold (≥threshold) for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) (S13a).

[0145] Accordingly, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can re-select / determine the combination with the largest number of Coverage In Bins (weight!= 0) classified in step S13a among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10) as the Cell Shape and Tilt for coverage expansion of the serving Cell (10) this time (S13b).

[0146] The O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can perform Cell Shape / Tilt optimization for the serving Cell (10) by transmitting the Cell Shape and Tilt values ​​of a re-selected combination for coverage expansion of the serving Cell (10) to the O-RU (10) of the serving Cell (10) and applying them (S17) (S20, S21, S22 of FIG. 5).

[0147] Meanwhile, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention, when interference mitigation is set as an intent for optimization (S13 No, S14 Yes), determines the strongest received signal strength (1) among a number of 3D Bins for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell. ST Highest SS-RSRP) and next highest received signal strength (2 nd The difference between the Highest SS-RSRP is less than the preset threshold difference ( <threshold) UE가 존재하는 중첩 Bin(weight!= 0)을 분류한다(S14a).

[0148] Accordingly, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can re-select / determine the combination with the smallest number of overlapping Bins (weight!= 0) classified in step S14a among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell, as the Cell Shape and Tilt for mitigating interference between the serving Cell (10) and the adjacent Cell (S14b).

[0149] The O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can perform Cell Shape / Tilt optimization for the serving Cell (10) and the adjacent Cell by transmitting and applying the Cell Shape and Tilt values ​​of the re-selected combination for interference mitigation to each O-RU (10) of the serving Cell (10) and the adjacent Cell (S17) (S20, S21, S22 of FIG. 5).

[0150] Meanwhile, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention, when Load balancing is set as an Intent for optimization (S14 No, S15 Yes), determines the strongest reception signal strength (1) among a number of 3D Bins for each combination of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell. ST Highest SS-RSRP) and next highest received signal strength (2 nd The difference between the Highest SS-RSRP is less than the preset threshold difference ( <threshold) UE가 존재하는 중첩 Bin(weight!= 0)을 분류한다(S15a).

[0151] And the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can re-select, as the Cell Shape and Tilt for load balancing of the serving Cell (10) and the adjacent Cell, the combination with the smallest sum of weights assigned to each Bin classified as an overlapping Bin among the combinations of Cell Shape and Tilt that can be supported by the serving Cell (10) and the adjacent Cell (S15b).

[0152] The O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can perform Cell Shape / Tilt optimization for the serving Cell (10) and the adjacent Cell by transmitting the Cell Shape and Tilt values ​​of the re-selected combination for load balancing to each O-RU (10) of the serving Cell (10) and the adjacent Cell so that they are applied (S17) (S20, S21, S22 of FIG. 5).

[0153] Meanwhile, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention may apply Cell Shape and Tilt as they are to the serving Cell (10) and adjacent Cells (S16) when the Intent for optimization is not set and the setting information as an Intent is not confirmed (S15 No).

[0154] Continuing the explanation with reference to FIG. 5 again, the O-RAN Cell control device (100, particularly the operation App (125)) of the present invention can request a response and application of the Cell Shape and Tilt values ​​re-selected according to the set Intent for the serving Cell (10) or the serving Cell (10) / adjacent Cell through Cell Shape / Tilt optimization in step S10 (S20, S21), and apply them to each corresponding O-RU (10) (S22). In response, each O-RU (10) can reply with a response according to the application of the Cell Shape and Tilt values ​​(S23).

[0155] Meanwhile, in the present invention, the serving Cell (10) or the O-RU (10) of the serving Cell (10) / adjacent Cell, which has applied the Cell Shape and Tilt values ​​re-selected as optimal through the Cell Shape / Tilt optimization performed in step S10, recognizes the occurrence of an event (e.g., change in Cell Shape / Tilt, etc.) according to the application this time, and collects the geographical UE distribution information in the changed Cell (Cell Shape / Tilt) in real time (S24) and transmits / uploads it to the O-RAN Cell control device (100, particularly the Cell Database (116)) of the present invention (S25).

[0156] As can be seen from the above description, according to the present invention, a specific Cell control technology configuration is realized that adaptively re-selects the optimal Cell Shape (and Tilt) that matches the operator's intent (e.g., coverage expansion, interference mitigation, load balancing) by reflecting the construction information of each Cell, information on Cell Shapes that can be supported, and dynamic environmental changes (e.g., Cell Add / Delete, UE and Traffic load changes, etc.).

[0157] In particular, the present invention realizes a new cell control technology configuration that adaptively re-selects the optimal cell shape (and tilt) by reflecting the subdivided adjacent cell shape (multiple 3D bins) specified by the serving cell and adjacent cell reflection area size, rather than considering only the serving cell.

[0158] Accordingly, according to the present invention, even in a multi-cell environment where different cell shapes are mixed / used in an O-RAN system, the optimal cell shape (and tilt) can be re-selected / applied to adaptively respond to dynamic environmental changes during operation, thereby having the effect of optimizing overall network performance through coverage hole improvement, interference mitigation, load balancing, etc.

[0159] A cell control method according to an embodiment of the present invention may be implemented in the form of program commands that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program commands, data files, data structures, etc., alone or in combination. The program commands recorded on the medium may be those specifically designed and configured for the present invention or may be those known and usable by those skilled in the art of computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specifically configured to store and execute program commands, such as ROMs, RAMs, and flash memories. Examples of program commands include not only machine language codes generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

[0160] Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to the above-described embodiments, and it will be understood that the technical idea of ​​the present invention extends to a range in which various modifications or changes can be made by anyone having ordinary skill in the art to which the present invention pertains without departing from the gist of the present invention as claimed in the following claims.

Claims

In the cell control device, memory containing instructions; and A cell control device characterized in that it includes a processor for specifying an adjacent cell to be reflected when a cell of a serving cell is changed based on the collected information collected for the cell by executing the above command, and re-selecting at least one of the cell shape and tilt for the serving cell by reflecting the cell shape of the specific adjacent cell. In the first paragraph, The adjacent cells to be reflected above are: A cell control device characterized in that, based on the construction information of each cell in the above-mentioned collected information, the cell is specified as belonging to the adjacent cell reflection area size based on the serving cell according to the adjacent cell reflection area size set for the cell change of the serving cell. In the first paragraph, The cell shape of the above specific adjacent cell is, A cell control device characterized in that it is composed of a plurality of three-dimensional bins created by dividing a three-dimensional space serviceable from a specific adjacent cell into preset unit lengths based on the construction information of each cell and the supportable cell shape information in the above-mentioned collected information. In the first paragraph, The above serving cell and adjacent cell are formed by RU (Radio Unit, O-RU) supporting Open RAN (Radio Access Network, O-RAN). The above processor, A cell control device characterized in that, when the cell of the serving cell is changed, information on the re-selected cell shape and tilt for the serving cell or the serving cell and an adjacent cell is transmitted to the O-RU of the serving cell or the serving cell and an adjacent cell. In the third paragraph, The above processor, For each combination of Cell Shape and Tilt that can be supported by the above serving Cell, Calculate the reception signal strength of the serving cell received in each of the above multiple 3D Bins, and determine that the Bin in which the calculated reception signal strength is greater than a preset threshold is a Coverage In Bin, A cell control device characterized in that, among the combinations of the above Cell Shape and Tilt, the combination that is determined to be the Coverage In Bin and has the largest number of Bins in which the UE exists is re-selected as the Cell Shape and Tilt for coverage expansion of the serving Cell. In the third paragraph, The above processor, For each combination of Cell Shape and Tilt that can be supported by the above serving Cell and adjacent Cell, Calculate the reception signal strength of the serving cell and adjacent cells received in each of the above multiple 3D bins, and determine that a bin in which the difference between the strongest reception signal strength and the next strongest reception signal strength among the above multiple 3D bins is less than a preset threshold difference is an overlapping bin, A cell control device characterized in that, among the combinations of the above Cell Shape and Tilt, a combination that is determined to be the overlapping Bin and has the smallest number of Bins in which a UE exists is re-selected as the Cell Shape and Tilt for mitigating interference between the serving Cell and adjacent Cells. In the third paragraph, The above processor, For each combination of Cell Shape and Tilt that can be supported by the above serving Cell and adjacent Cell, Calculate the reception signal strength of the serving cell and adjacent cells received in each of the above multiple 3D bins, and determine that a bin in which the difference between the strongest reception signal strength and the next strongest reception signal strength among the above multiple 3D bins is less than a preset threshold difference is an overlapping bin, A cell control device characterized in that, among the combinations of the above Cell Shape and Tilt, the combination with the smallest sum of weights assigned according to the number of UEs present in each Bin determined to be the overlapping Bin is re-selected as the Cell Shape and Tilt for load balancing of the serving Cell and adjacent Cell. In a cell control method performed in a cell control device, A step of specifying an adjacent cell to be reflected in a cell change of a serving cell based on the collected information about the cell; A cell control method characterized in that, when the cell of the serving cell is changed, the method includes a step of re-selecting at least one of the cell shape and tilt for the serving cell by reflecting the cell shape of the specific adjacent cell. In paragraph 8, The cell shape of the above specific adjacent cell is, A cell control method characterized in that it is composed of a plurality of 3D bins created by dividing a 3D space serviceable from a specific adjacent cell into preset unit lengths based on the construction information of each cell and the supportable cell shape information in the above-mentioned collected information. In paragraph 9, The above re-selection step is: For each combination of Cell Shape and Tilt that can be supported by the above serving Cell and adjacent Cell, Using the signal strength received from the serving cell and adjacent cells in each of the above multiple 3D bins and the weights assigned according to the number of UEs present in each bin, at least one condition among coverage expansion of the serving cell, interference mitigation between the serving cell and adjacent cells, and load balancing is confirmed. A cell control method characterized in that a combination satisfying the above-mentioned conditions among the above-mentioned combinations of Cell Shape and Tilt is re-selected as the Cell Shape and Tilt of the serving Cell and the adjacent Cell. A step of specifying an adjacent cell to be reflected in the cell change of the serving cell based on the collected information about the cell, combined with the hardware of the cell control device. A computer program characterized in that it is stored in a medium to execute a step of re-selecting at least one of Cell Shape and Tilt for the serving Cell by reflecting the Cell shape of the specific adjacent Cell when the Cell of the serving Cell is changed.

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