Control for base station operation at the time of loss of coverage

Abstract

In the present invention, an information processing device includes a first extraction process, an acquisition process, a prediction process, and a scheduling process. The first extraction process extracts one or more base stations that can be driven by a standby power supply, from among base stations for which a loss of coverage was detected. The acquisition process acquires an importance map in which the importance at the time of loss of coverage is associated with the geographical coordinates. The prediction process configures a plurality of sector groups from one or more base station sectors, weights each of the plurality of sector groups according to the importance defined in the importance map, and predicts coverage for a coverage loss area that should be covered by the base station for which a loss of coverage was detected. The scheduling process schedules operations of each of the plurality of sector groups to provide compensatory coverage for the coverage loss area.

Description

Control for base station operation during loss of coverage

[0001] The present disclosure relates to control for base station operation during loss of coverage.

[0002] The information provided in this Background section is intended only to enhance understanding of the general background of the present disclosure and should not be construed as an admission that the information is prior art known to those of ordinary skill in the art, nor should it be construed as suggesting in any way that prior art is known to those of ordinary skill in the art.

[0003] In a mobile network, a base station constitutes a front-end radio access network (RAN) and operates as a node that provides communication services to user equipment (UE). Typically, these base stations are equipped with backup power sources, such as lead-acid batteries and emergency gas generators, so that communication services to UEs within the coverage area of ​​the base station are not immediately interrupted in the event of a power outage or disaster that causes a loss of power from the main power source. When a power outage or disaster occurs and the base station loses its main power source, these backup power sources are driven to supply power to the base station, thereby enabling the base station to continue providing communication services to UEs within the coverage area powered by the backup power source.

[0004] Emergency backup power sources are limited resources, and the period during which they can continue to supply power to base stations is usually only a few hours. For this reason, attempts have been made to extend the duration of communication services by reducing the power consumption required to provide communication services from base stations while the backup power source is supplying power to the base station.

[0005] Patent Document 1 discloses a base station control device that puts a base station into a power saving mode when a storage battery starts supplying power to the base station due to a power outage, etc. Specifically, when there is a mobile station in communication with a base station being powered by a storage battery and there is another base station in communication or available to communicate with this communicating mobile station, the control device in Patent Document 1 attempts to save power at the base station while maintaining the communication state of the mobile station by stopping communication between the base station being powered by a storage battery and the communicating mobile station.

[0006] JP 2015-15538 A

[0007] However, when a disaster such as a large-scale natural disaster occurs, power loss can occur over a wide area, and recovery from the power loss can take a long time. Therefore, even if a certain degree of power saving is implemented in base stations installed in the affected area, it is difficult for the base stations to continue providing communication services until recovery by using power supplied from a backup power source. Therefore, there is a risk that communication services for many UEs of many users in areas where coverage has been lost due to the disaster will be interrupted before recovery, thereby reducing the availability of mobile communications.

[0008] Therefore, an object of the present disclosure is to improve communication availability by providing communication services for a longer period of time when coverage is lost.

[0009] In order to solve the above problem, one aspect of an information processing device according to the present disclosure is an information processing device that executes a first extraction process that extracts one or more base stations that can be driven by a backup power source from among base stations in which a coverage loss has been detected; an acquisition process that acquires an importance map that associates importance at the time of coverage loss with geographical coordinates; a prediction process that forms a plurality of sector groups from sectors of the one or more base stations and weights each of the plurality of sector groups by an importance defined in the importance map to predict coverage for a coverage loss area that should be covered by the base station in which the coverage loss has been detected; and a scheduling process that schedules operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

[0010] In order to solve the above-described problems, one aspect of the information processing method according to the present disclosure is an information processing method executed by an information processing device, the information processing method including: extracting one or more base stations that can be driven by a backup power source from among base stations in which a coverage loss has been detected; obtaining an importance map that associates importance at the time of coverage loss with geographical coordinates; configuring a plurality of sector groups from the sectors of the one or more base stations; weighting each of the plurality of sector groups by an importance defined in the importance map; predicting coverage for a coverage loss area that should be covered by the base station in which the coverage loss has been detected; and scheduling operation of each of the plurality of sector groups to compensate for the coverage loss area based on the predicted coverage.

[0011] In order to solve the above problem, one aspect of an information processing system according to the present disclosure is an information processing system that executes a first extraction process that extracts one or more base stations that can be driven by a backup power source from among base stations in which a coverage loss has been detected; an acquisition process that acquires an importance map that associates importance at the time of coverage loss with geographical coordinates; a prediction process that forms a plurality of sector groups from sectors of the one or more base stations and weights each of the plurality of sector groups by an importance defined in the importance map to predict coverage for a coverage loss area that should be covered by the base station in which the coverage loss has been detected; and a scheduling process that schedules operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

[0012] According to one aspect of the present disclosure, it is possible to improve communication availability by providing communication services for a longer period of time during a loss of coverage. The above-mentioned objects, aspects, and advantages of the present invention as well as other objects, aspects, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of the invention, when read in conjunction with the accompanying drawings and the claims.

[0013] Features, aspects, and advantages of embodiments of the present disclosure will be described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same elements. FIG. 1 is a conceptual diagram illustrating an example of a network configuration of a mobile network in which a base station operation control device according to an embodiment of the present disclosure is implemented. FIG. 2 is a block diagram illustrating an example of a relationship between a virtualization platform on which the mobile network of FIG. 1 can be implemented and a base station operation control device according to an embodiment of the present disclosure. FIG. 3 is a block diagram illustrating an example of a functional configuration of a base station operation control device according to an embodiment of the present disclosure. FIG. 4 is a flowchart illustrating an example of an outline of a base station operation control process executed by a base station operation control device according to an embodiment of the present disclosure. FIG. 5 is a flowchart illustrating an example of a detailed process of a coverage compensation process (first coverage compensation process) by an adjacent healthy base station in step S2 of FIG. 4. FIG. 6A is a schematic diagram illustrating an example of a coverage area under normal conditions provided by multiple base stations. FIG. 6B is a schematic diagram illustrating an example of a base station that has lost power during a disaster and an area where coverage has been lost in the coverage area of ​​FIG. 6A. FIG. 7A is a schematic diagram illustrating an example of healthy base stations adjacent to the coverage loss area of ​​FIG. 6B and corresponding coverage areas. FIG. 7B is a schematic diagram illustrating an example of a state in which the coverage of the coverage loss area is compensated for by the adjacent healthy base station of FIG. 7A. FIG. 8 is a flowchart illustrating an example of detailed processing procedures for the coverage compensation process (second coverage compensation process) by a backup power base station in step S4 of FIG. 4. FIG. 9A is a schematic diagram illustrating an example of a state in which the importance of each point is defined in an importance map stored in an importance map storage device according to an embodiment of the present disclosure. FIG. 9B is a schematic diagram illustrating an example of a state in which the coverage loss area and the coverage compensation area by the backup power base station are mapped on the importance map of FIG. 9A. FIG. 10 is a schematic diagram illustrating an example of a state in which the importance gradient is continuously defined in the importance map of FIG. 9B. FIG. 11A is a schematic diagram illustrating an example of a first state in which the coverage of the coverage loss area is compensated for by the backup power base station. FIG. 11B is a schematic diagram illustrating an example of a second state in which coverage in the coverage loss area is compensated for by the backup power supply-driven base station.11C is a schematic diagram illustrating an example of a third state in which coverage of a coverage loss area is compensated for by a backup power supply driven base station. FIG. 12 is a sequence diagram showing an example of a communication sequence for base station operation control processing when power is lost between a base station operation control device according to an embodiment of the present disclosure and each base station. FIG. 13 is a block diagram showing an example of a hardware configuration of a base station operation control device according to an embodiment of the present disclosure.

[0014] Exemplary embodiments will now be described in detail with reference to the accompanying drawings. While the present disclosure presents illustrations and descriptions, it is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Modifications and variations are possible in light of the present disclosure and may be acquired from practice of the embodiments. Furthermore, one or more features or components of one embodiment may be incorporated into or combined with another embodiment (or may be incorporated into or combined with one or more features of another embodiment). The flowcharts and descriptions of the operations presented below relate to at least one embodiment of the present disclosure. However, it should be noted that other embodiments may be created that do not exactly match the flowcharts and descriptions. It should also be understood that in other embodiments, one or more operations may be omitted, one or more operations may be added, or one or more operations may be performed simultaneously (at least partially).

[0015] It should be apparent that the systems, methods, or both described herein may be implemented in various forms of hardware, software, or a combination of hardware and software. Furthermore, the actual specific control hardware or software code used to implement these systems, methods, or both should not limit their implementation. Thus, the operation and behavior of the systems, methods, or both will be described herein without reference to specific software code. It should also be understood that software and hardware may be designed to implement the systems, methods, or both based on the description herein.

[0016] Although a particular combination of features may be recited in the claims and / or disclosed in the specification, it is not intended that the disclosure of embodiments be limited to that particular combination. Moreover, many of these features may be combined in ways not specifically recited in the claims, or not disclosed in the specification, or both. Also, even if a dependent claim depends directly on only one claim, the disclosure of embodiments may include combinations of that dependent claim with each claim recited in the claims.

[0017] No element, act, or instruction used herein should be construed as critical or essential unless expressly stated as such. Furthermore, herein, nouns not referred to in the plural (such as when the English articles "a" and "an" are used with a noun) are intended to include one or more of that noun and may be used interchangeably with "one or more." Furthermore, as used herein, terms such as "have," "having," "include," and "comprises" are intended to be open-ended terms, i.e., may have or include other elements, etc. Furthermore, the phrase "based on" is intended to mean "based at least in part on," unless otherwise specified. Furthermore, phrases such as "at least one of [A] and [B]," "[A] and / or [B]," or "at least one of [A] or [B]" should be understood to include only A, only B, or both A and B.

[0018] The following describes an example in which a base station operation control device according to an embodiment of the present disclosure is implemented in a server device or server system constituting a core network, communicates with base stations via a mobile network, extracts one or more base stations that can be driven by a backup power source from among base stations for which coverage loss has been detected, predicts coverage for an area to be covered by the base station for which coverage loss has been detected for each of a plurality of sector groups composed of sectors of one or more base stations, and schedules operation of each of the plurality of sector groups based on the predicted coverage. In the exemplary embodiment, when predicting the coverage for each of the plurality of sector groups, a criticality map is applied that associates the criticality at the time of coverage loss with geographical coordinates. Hereinafter, in this embodiment, "coverage" refers to a geographical range in which radio waves for mobile communications, etc., can be transmitted and received.

[0019] However, this embodiment is not limited to this. All or part of the functions of the base station operation control device according to this embodiment may be implemented on the backhaul network or radio access network side. Alternatively, in order to execute base station operation control processing for a more limited area, all or part of the functions of the base station operation control device according to this embodiment may be implemented in a Multi-access Edge Computing (MEC) server installed as an edge node close to the base station.

[0020] <Network Configuration of a Network Implementing a Base Station Operation Control Device According to an Embodiment of the Present Disclosure> Figure 1 is a conceptual diagram showing an example of the network configuration of a mobile network in which a base station operation control device according to an embodiment of the present disclosure is implemented. The mobile network shown in Figure 1 includes a Radio Access Network (RAN) 103, backhaul networks 104a and 104b, and a core network 105. The RAN 103 includes base station sites 101a and 101b and user equipment (UE) 102a and 102b.

[0021] The mobile network shown in Figure 1 may be a fifth-generation mobile communication system (5G) conforming to the 3GPP (registered trademark) standard, or may be a fourth-generation mobile communication system (4G) or other generation mobile communication system. The mobile network shown in Figure 1 may also be a virtualized network built on a virtualization platform. In this case, the physical network is virtualized, and end-to-end network functions spanning the RAN 103, backhaul networks 104a and 104b, and core network 105 are realized by the virtualized network on a general-purpose server or cloud.

[0022] The base station sites 101a and 101b are equipped with antennas, remote radio heads (RRHs), radio interface units (RIUs) that are line termination devices, and transmit and receive radio signals to and from UEs 102a and 102b, respectively, via the antennas of the base station sites 101a and 101b. The base station sites 101a and 101b are also referred to as antenna sites, but will hereinafter be simply referred to as "base stations." The base stations 101a and 101b are gNodeBs in a 5G mobile network and eNodeBs in a 4G mobile network. However, the base stations 101a and 101b shown in FIG. 1 do not necessarily represent a single physical base station device, but may instead be composed of one or more slave stations and a master station that accommodates the multiple slave stations via a fronthaul network.

[0023] The base stations 101a and 101b are edge nodes that transmit and receive radio signals to and from the UEs 102a and 102b via antennas and constitute the RAN 103 of the mobile network. The base stations 101a and 101b receive attach requests from the UEs 102a and 102b and connect the UEs 102a and 102b to a core network 105 via fronthaul networks and backhaul networks 104a and 104b. As a result, the base stations 101a and 101b relay data transfer between the UEs 102a and 102b and the Internet 106, and voice calls between the UEs 102a and 102b and a public switched telephone network (PSTN) 107. The base stations 101a and 101b may be equipped with a backup power supply that supplies power to the base stations 101a and 101b in the event of a loss of the main power supply. The backup power source may be, for example, a lead-acid battery or an emergency gas generator, and may or may not be installed depending on the coverage area and installation scale of the base stations 101a and 101b.

[0024] The UEs 102a and 102b are devices that are wirelessly connected to the base stations 101a and 101b within the coverage areas of the base stations 101a and 101b and are capable of mobile communication via the base stations 101a and 101b. The UEs 102a and 102b may be any devices, such as mobile terminals such as smartphones, mobile phones, tablet terminals, and personal computers (PCs), mobile objects such as vehicles, and device-integrated terminals such as sensors, as long as they are capable of mobile communication via the base stations 101a and 101b. The number of base stations 101a and 101b and the number of UEs 102a and 102b are not limited to the numbers shown in FIG. 1 and may be any number.

[0025] In the mobile network, the RAN 103 is a network for connecting the UEs 102a and 102b to the core network 105 via wireless connections with the base stations 101a and 101b. The backhaul networks 104a and 104b relay the RAN 103, which is a base station-side network, to the core network 105. The core network 105 is a high-capacity backbone network used by the mobile network as the hub of mobile communications, connecting between concentrators, base stations, operators, etc.

[0026] <Network Configuration of a Network Implementing a Base Station Operation Control Device According to an Embodiment of the Present Disclosure> Fig. 2 is a block diagram showing an example of the relationship between a virtualization platform on which the mobile network of Fig. 1 can be implemented and a base station operation control device according to an embodiment of the present disclosure. With reference to Fig. 2 , a Network Function Virtualization Infrastructure (NFVI) 21 is an infrastructure for network virtualization and is configured to include physical resources, a virtualization layer, and virtualized resources. The physical resources include hardware resources such as computing resources, storage, and transmission resources. The virtualization layer is configured with a hypervisor and the like for virtualizing the physical resources and providing them to a Virtualized Network Function (VNF) 22. The virtualized resources are virtualized resources provided to the VNF 22.

[0027] That is, the NFVI 21 is an infrastructure that enables hardware resources, which are physical resources that realize computing, storage, transmission, etc., to be flexibly handled as virtualized hardware resources that are virtualized by a virtualization layer such as a hypervisor. A plurality of general-purpose servers that constitute the NFVI 21 in FIG. 2 may be arranged in the backhaul networks 104a, 104b, the core network 105, etc.

[0028] The VNF 22 is a set of virtualized network functions that are arranged on physical resources and virtualized resources and correspond to each application that runs on a virtual machine (VM) on a general-purpose server, and realizes network functions in software. Each VNF 22 may be provided with an Element Manager (EM), which is a management function for the VM.

[0029] The Management and Orchestration (MANO) 23 has a function of managing and orchestrating the virtualized environment configured by the NFVI 21 and the VNF 22. The MANO 23 includes a Virtualized Infrastructure Manager (VIM) 231, a VNF Manager (VNFM) 232, and an NVF Orchestrator (NVFO) 233.

[0030] The VIM 231 operates and manages the physical resources and virtualized resources used by the VNFs 22. The VNFM 232 deploys a set of network functions for each VNF 22 on the physical resources and virtualized resources, and manages the lifecycle of each VNF 22. The deployed set of network functions includes communication functions, service application functions, and data transfer protocols required to provide services. The VNFM 232 may be a dedicated VNFM dedicated to each VNF 22, or a general-purpose VNFM provided for two or more VNFs 22.

[0031] The NFVO 233 orchestrates the resources of the NFVI 21, allocates the set of network functions of the VNF 22, and performs integrated operation and management of the entire system. The NFVO 233 executes processing according to instructions from an Operation Support System (OSS) / Business Support System (BSS) 24.

[0032] The OSS / BSS 24 is the highest layer of the virtualized network and is a system that monitors and manages service instances corresponding to applications provided to end users. The OSS is a system required for building and operating each service instance, and the BSS is a system required for billing, customer information management, etc.

[0033] The base station operation control device 1 is communicably connected to the NFVI 21, the OSS / BSS 24, and the MANO 23, and executes the base station operation control process according to this embodiment. While Fig. 2 shows an example in which the base station operation control device 1 is implemented in a node separate from each node of the virtualization platform, this embodiment is not limited to this. For example, the base station operation control device 1 may be implemented as part of the OSS / BSS 24 or as part of the MANO 23.

[0034] <Functional Configuration of Base Station Operation Control Device> Fig. 3 is a block diagram showing an example of the functional configuration of a base station operation control device according to an embodiment of the present disclosure. Referring to Fig. 3, the base station operation control device 1 includes a monitoring unit 11, an operation control unit 12, a coverage information management unit 13, a coverage prediction unit 14, an operation scheduler 15, and a base station setting unit 16.

[0035] The base station operation control device 1 is configured to be able to access the importance map storage device 2 and the base station information storage device 3, and can read, add, update, delete, and so on, data stored in these storage devices. The importance map storage device 2 is a storage device that stores an importance map applied in the coverage compensation process of this embodiment. The importance map is a map that associates the importance of coverage compensation in the event of coverage loss, i.e., the importance of providing continuous communication, with geographical coordinates, and the importance is defined as a function of the geographical coordinates. Details of this map will be described later with reference to Figures 9A to 10. The base station information storage device 3 is a storage device that stores base station information that is referenced and updated in the base station operation control process of this embodiment. The base station information includes information about each base station, such as the deployment locations of the base stations 101a and 101b, deployed resources and versions, the presence and capacity of backup power sources, information about neighboring nodes including neighboring base stations, and operating status. The importance map storage device 2 and the base station information storage device 3 may each be configured with a non-volatile storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive), or may be configured with a network-attached NAS (Network Attached Storage).

[0036] The monitoring unit 11 constantly monitors the operating status of the base stations 101a, 101b and each node constituting the other mobile network, detects the occurrence of power loss or power restoration, equipment failure or equipment operation error, communication failure or communication error, and other events, and notifies the operation control unit 12 of the detected events. The monitoring unit 11 may detect power loss or power restoration or other events in the monitored nodes by an alert from the node where the failure occurred, its adjacent node, or a management node, or may detect the events by periodically issuing polling to each node.

[0037] The operation control unit 12 cooperates with each component 11, 13 to 16 of the base station operation control device 1 to comprehensively control the base station operation control process according to this embodiment. Specifically, the operation control unit 12 controls the monitoring unit 11 to monitor the operating status of each node constituting the mobile network, particularly the base stations 101a and 101b. When a power loss of the base station 101a or 101b is detected, the operation control unit 12 controls the coverage prediction unit 14 and the operation scheduler 15 to generate setting parameters and an operation schedule for a target base station that compensates for the coverage of the area where coverage has been lost due to the power loss of the base station 101a or 101b, and distributes these to the target base station via the base station setting unit 16. In this embodiment, the base station operation schedule is created so as to maximize the coverage of the area where power has been lost according to its importance, while reducing the power consumption of the entire group of target base stations that compensate for the coverage of the area where power has been lost, thereby enabling communication services to be provided for a longer period of time.

[0038] The coverage information management unit 13 manages coverage information that can be referenced to compensate for coverage loss in an area where coverage has been lost due to a power loss (hereinafter referred to as a "coverage loss area"). For example, the coverage information that can be referenced includes the importance map stored in the importance map storage device 2, the base station information stored in the base station information storage device 3, and the occurrence and progress of failures such as disasters. The coverage information management unit 13 may sequentially update the importance map and base station information in accordance with the operating status of each node constituting the mobile network, particularly the base stations 101a and 101b, the occurrence and progress of failures, and changes in importance over time in the importance map, all of which are supplied from the monitoring unit 11.

[0039] The coverage prediction unit 14 accesses the importance map storage device 2 and the base station information storage device 3 via the coverage information management unit 13 based on a coverage prediction command from the operation control unit 12, executes coverage prediction in the coverage compensation processing according to this embodiment, and supplies the coverage prediction result to the operation control unit 12 and the operation scheduler 15. Details of this coverage compensation processing will be described later with reference to Figures 5 to 11B.

[0040] The operation scheduler 15 creates an operation schedule for the target base station determined to compensate for the coverage of the coverage-lost area based on an operation schedule creation command from the operation control unit 12 and in accordance with the prediction result of the coverage prediction unit 14, and supplies the created operation schedule to the operation control unit 12 and the base station setting unit 16. The operation schedule created by the operation scheduler includes setting parameters to be set in each target base station and an operation schedule. Based on an operation schedule setting command from the operation control unit 12, the base station setting unit 16 distributes the operation schedule for the target base station created by the operation scheduler 15 to the target base station determined to compensate for the coverage of the power-loss area, and causes it to set it.

[0041] <Processing Procedure of Base Station Operation Control Processing in Base Station Operation Control Device> Fig. 4 is a flowchart showing an example of an outline processing procedure of a base station operation control processing executed by the base station operation control device 1 according to an embodiment of the present disclosure. Referring to Fig. 4, the base station operation control processing is executed by each component of the base station operation control device 1.

[0042] In step S1, the monitoring unit 11 of the base station operation control device 1 detects a power loss at the base stations 101a and 101b and notifies the operation control unit 12 of the detected power loss at the base stations 101a and 101b. The power loss at the base stations 101a and 101b detected by the monitoring unit 11 can typically occur over a wide area and for a long period of time in the event of a large-scale natural disaster such as an earthquake or tsunami or a large-scale power outage. However, this embodiment is not limited to this and may be caused by any external or internal factor, such as equipment failure at each base station, network failure, or software or hardware malfunction. The monitoring unit 11 may notify the operation control unit 12 of the detected power loss at the base stations 101a and 101b together with an error code or log acquired in connection with the power loss, a status code indicating the type and status of the failure, and the like. The operation control unit 12 groups the base stations in which a power loss has been detected based on the monitoring results of the status of each base station provided by the monitoring unit 11 and the base station information stored in the base station information storage device 3, particularly information on the deployment location of the base station. The operation control unit 12 may specify the coverage loss area that should be covered by the group of base stations in which the power loss has been detected as the target area for coverage compensation.

[0043] In step S2, the operation control unit 12 of the base station operation control device 1 controls the coverage information management unit 13, the coverage prediction unit 14, and the operation scheduler 15 to first perform a first coverage compensation process, in which coverage compensation is performed by base stations adjacent to the power-loss-affected base stations 101a and 101b and that are operating normally. Details of this first coverage compensation process will be described later with reference to FIGS. 5 to 7B. In step S3, the operation control unit 12 of the base station operation control device 1 determines whether or not there are any uncompensated areas among the coverage loss areas of the power-loss-affected base stations 101a and 101b that have not yet been compensated after the first coverage compensation process of step S2 is performed. If there are no uncompensated areas (step S3: N), the operation control unit 12 skips steps S4 and S5 and terminates the base station operation control process shown in FIG. 4. On the other hand, if there are any uncompensated areas (step S3: Y), the operation control unit 12 proceeds to step S4. In step S4, the operation control unit 12 of the base station operation control device 1 controls the coverage information management unit 13, the coverage prediction unit 14, and the operation scheduler 15 to perform coverage compensation by base stations that can be driven by standby power sources within the uncompensated area as a second coverage compensation process. Details of this second coverage compensation process will be described later with reference to Figures 8 to 11C.

[0044] In step S5, the operation control unit 12 of the base station operation control device 1 determines whether the power of the base stations 101a and 101b that have lost power has been restored. The operation control unit 12 may detect the restoration of power to the base stations 101a and 101b that have lost power, based on the monitoring results of the status of each base station that are sequentially updated by the monitoring unit 11. If the power of any of the base stations 101a and 101b that have lost power has not yet been restored (step S5: N), the operation control unit 12 returns to step S1 and continues the base station operation control process. On the other hand, if the power of all of the base stations 101a and 101b that have lost power has been restored (step S5: Y), the operation control unit 12 ends the base station operation control process shown in FIG. 4.

[0045] 4 shows an example in which the first coverage compensation process is executed, and if there is an uncompensated area, the second coverage compensation process is executed subsequently as a complement, but this embodiment is not limited to this. For example, the first coverage compensation process and the second coverage compensation process may be executed independently, in any order, or simultaneously in parallel.

[0046] <Processing Procedure of First Coverage Compensation Processing> Figure 5 is a flowchart showing an example of detailed processing procedures for coverage compensation processing (first coverage compensation processing) by an adjacent healthy base station in step S2 of Figure 4. When a power loss of a base station is detected in step S1 of Figure 4, in step S21 of Figure 5, the operation control unit 12 of the base station operation control device 1 extracts healthy base stations adjacent to a coverage loss area where coverage has been lost due to the power loss of the base station. A healthy base station refers to a base station that is operating on its main power source and capable of wireless communication with UEs 102a and 102b without any failure in the main power source used by the base station under normal circumstances. However, depending on the situation, neighboring base stations that can be powered by a backup power source may also be added to the healthy base stations. Specifically, the operation control unit 12 may extract healthy base stations adjacent to a coverage loss area via the coverage information management unit 13 based on information, particularly information such as the base station deployment location and main power capacity, from the base station information stored in the base station information storage device 3.

[0047] In step S2, the operation control unit 12 selects a sector of an adjacent healthy base station heading in the direction of the coverage loss area where power has been lost from among all sectors of the adjacent healthy base stations extracted in step S1. The sector of the adjacent healthy base station selected in step S2 has its setting parameters, such as transmission power density, tilt, azimuth, etc., optimized for coverage compensation in the coverage loss area, and becomes the sector used for coverage compensation in the power loss area.

[0048] FIG. 6A is a schematic diagram illustrating an example of a coverage area under normal conditions provided by multiple base stations. FIG. 6B is a schematic diagram illustrating an example of a base station that has lost power during a disaster and an area where coverage has been lost in the coverage area of ​​FIG. 6A. Referring to FIG. 6A, the coverage areas of the multiple base stations are each shown as a circle, with base station 61 located at the center of each circular coverage area, indicated by a star. In FIG. 6A, base station 61 is equipped with three sector antennas that radiate radio wave beams in three directions, and base station 61's coverage area 62 is divided into three sectors 63, 64, and 65. The same applies to the other circular coverage areas in FIG. 6A. The coverage areas of the multiple base stations are arranged vertically and horizontally, partially overlapping each other. Note that the arrangement of the coverage areas in FIG. 6A is merely an example for illustrative purposes and may be arranged arbitrarily. Base stations may be equipped with any number of sector antennas or omnidirectional antennas.

[0049] Referring to FIG. 6B, suppose that a disaster or other event occurs and causes power loss for base stations 66a to 66g in the coverage area of ​​FIG. 6A. In this case, of the coverage areas of the seven base stations 66a to 66g that have lost power, an area excluding overlapping areas with the coverage areas of base stations operating normally is detected as a coverage loss area 67. It is assumed that the accommodating station (Group Unit Center: GC) that accommodates the base stations 66a to 66g that have lost power is operating normally and is capable of communicating with the base station operation control device 1 on the core network 105 side. FIG. 7A is a schematic diagram illustrating an example of adjacent healthy base stations adjacent to the coverage loss area 67 of FIG. 6B and corresponding coverage areas. Referring to FIG. 7A, base stations 71a to 71l that are geographically adjacent to the coverage loss area 67 and operating normally with normal power sources are extracted as adjacent healthy base stations 71a to 71l. The normal coverage areas corresponding to these neighboring healthy base stations 71 a to 71 l are arranged around the coverage loss area 67 .

[0050] 5 , in step S23, the operation control unit 12 of the base station operation control device 1 adjusts the transmission power value of the sector of the adjacent healthy base station selected in step S22 so as to maximize the overlapping area with the coverage loss area 67. Specifically, the operation control unit 12 sets, for each of the selected sectors of the adjacent healthy base stations 71 a to 71 l, a transmission power value that maximizes the overlapping area with the coverage loss area 67 within the maximum allowable range of transmission power set for the sector antenna of each sector, and executes processing to calculate a coverage compensation area within the coverage loss area 67 where coverage is compensated.

[0051] After the adjustment of the transmission power values ​​in step S23 is performed for all sectors selected in step S22, the operation control unit 12 determines in step S24 whether there are any uncompensated areas in the coverage loss area 67, where coverage has not yet been compensated. If it is determined that there are no uncompensated areas (step S24: N), the operation control unit 12 skips steps S25 to S27, terminates the first coverage compensation process, and proceeds to step S3 in FIG. 4. On the other hand, if it is determined that there are any uncompensated areas (step S24: Y), the operation control unit 12 proceeds to step S25. Note that when adjusting the transmission power values ​​of the selected sectors in step S23, the operation control unit 12 may refer to the importance map stored in the importance map storage device 2 and adjust the transmission power values ​​of the selected sectors so that specific points in the importance map are always covered, or by weighting according to the importance gradient defined in the importance map, so that important points or important areas are more reliably covered.

[0052] In step S25, the operation control unit 12 determines the parameters to be set for each sector of the adjacent healthy base stations 71a to 71l selected in S22 so as to best compensate for the uncompensated area. Specifically, the parameters to be set for each sector determined in S25 may include the transmit power density, tilt (tilt angle), and azimuth (azimuth angle) of each sector antenna. Power density refers to the power per bandwidth and is calculated according to the following formula: Pd = P / B (Formula 1). Here, Pd is the power density (W / Hz), P is the power (W), and B is the bandwidth (Hz). For a given transmit power, narrowing the bandwidth used for the transmitted radio waves can increase the transmit power density and extend the communication distance. Furthermore, by changing the tilt and azimuth of the sector antenna, radio waves can be emitted in a manner that points them toward the target base station or target location in the power loss area.

[0053] The operation control unit 12 may first calculate the maximum transmission power density, tilt, and azimuth settings for each sector so that the overlap area with the uncompensated area is maximized, and then adjust the transmission power density, tilt, azimuth, etc. between each sector and other sectors so that each sector generates the minimum necessary coverage for the point that should be the target of coverage compensation. Here, when calculating the maximum transmission power density setting value, a condition such as "coverage before the setting value is changed must be guaranteed to be 90% or more" may be set. This makes it possible to suppress a decrease in coverage of adjacent healthy base stations before the parameter setting value is changed, and to maintain, as much as possible, the coverage that the sectors of adjacent healthy base stations should originally cover. As in step S23, when adjusting the transmission power density, tilt, and azimuth of the selected sector in step S25, the operation control unit 12 may refer to the importance map stored in the importance map storage device 2 and adjust the transmission power density, tilt, and azimuth of the selected sector so that specific points in the importance map are always covered, or by weighting according to the importance gradient defined in the importance map, so that important points or important areas are more reliably covered.

[0054] In step S26, the operation control unit 12 determines a sector or a set of sectors that can compensate for the coverage of the uncompensated area as a result of adjusting the parameters in step S25. Here, communication throughput is proportional to the bandwidth used. Therefore, narrowing the bandwidth used to increase the transmission power density to the uncompensated area may result in a decrease in overall throughput.

[0055] In this embodiment, the set of sectors is determined by adjusting the transmission power density of the selected sectors. Furthermore, before narrowing the bandwidth used by the selected sectors to increase the transmission power density, a step of increasing the transmission power density by increasing the transmission power value without changing the bandwidth used is performed. This ensures that more uncompensated areas can communicate with at least one sector, while avoiding an excessive increase in power density that is ineffective for coverage compensation, thereby minimizing a decrease in throughput in the coverage area of ​​an adjacent healthy base station. In step S27, the operation control unit 12 transmits the parameter setting values ​​determined in S25 via the base station setting unit 16 to adjacent healthy base stations having target sectors for compensating the coverage of the coverage loss area 67.

[0056] 7B is a schematic diagram illustrating an example of a state in which coverage of the power loss area is compensated for by the neighboring healthy base station of FIG. 7A. Referring to FIG. 7B, as a result of executing the first coverage compensation process from steps S21 to S27 of FIG. 5, neighboring healthy base stations 71b, 71d, 71f, 71h, 71i, and 71l are selected from the neighboring healthy base stations 71a to 71l extracted in step S21. Then, parameter setting values ​​of the sectors of these neighboring healthy base stations 71b, 71d, 71f, 71h, 71i, and 71l facing the coverage loss area 67 are changed. For example, for neighboring healthy base station 71b, the transmission power density of sectors 73 and 74 facing the coverage loss area 67 is increased, extending coverage toward the power loss area 67. FIG. 7B shows the shaded sectors 73 and 74 having extended coverage. The same is true for the other selected neighboring healthy base stations 71 d, 71 f, 71 h, 71 i, and 71 l. It can be seen that the coverage loss area 67 shown in Figure 6B has been reduced to the uncompensated area 75 shown in Figure 7B, and the coverage lost in the coverage loss area 67 has been compensated for up to the periphery of the uncompensated area 75.

[0057] 5 shows an example in which the transmission power density is increased without changing the band used in step S23, and if there is an uncompensated area, the transmission power density is increased by narrowing the band used in step S25, but this embodiment is not limited to this. For example, the transmission power density increasing process in step S23 and the transmission power density increasing process in step S25 may be performed independently, in any order, or simultaneously in parallel.

[0058] <Processing Procedure of Second Coverage Compensation Processing> Figure 8 is a flowchart showing an example of detailed processing procedures for coverage compensation processing (second coverage compensation processing) by a backup power base station in step S4 of Figure 4. The second coverage compensation processing is a process in which, among base stations in a power loss area that have lost power, a base station that can be operated by a backup power source compensates for the coverage of an uncompensated area where coverage has not yet been compensated by an adjacent healthy base station. In the second coverage compensation processing, when compensating for the coverage of an uncompensated area using a base station operated by a backup power source with a limited operating time, the base station operation control device 1 predicts the coverage compensation rate using variable parameters such as the on / off state of radio wave radiation of the base station cell, the transmission power density, tilt, and azimuth, and determines multiple groups of backup power base stations to be operated simultaneously and rotates these multiple base station groups over time. This reduces power consumption throughout the power loss area while maintaining at least a certain level of coverage compensation in the power loss area, thereby extending the continuation of communication services. The extent of coverage compensation may be determined appropriately depending on the situation. For example, if the requirement is to ensure that the duration of communication service reaches a target value, maximum coverage compensation may be performed to just barely meet the requirement. Alternatively, for example, minimum coverage compensation may be performed, prioritizing maximizing the duration of communication service.

[0059] If an uncompensated area remains after the first coverage compensation process is executed in step S3 of Fig. 4, in step S41 of Fig. 8, the operation control unit 12 of the base station operation control device 1 extracts base stations that can be driven by backup power from among the base stations that have lost power and are located within the uncompensated area 75 of Fig. 7B. Specifically, the operation control unit 12 may extract base stations that can be driven by backup power and are located in the coverage loss area via the coverage information management unit 13 based on the base station information stored in the base station information storage device 3, particularly information on the deployment location of the base station and the presence and capacity of a backup power source. The operation control unit 12 may also receive, via the monitoring unit 11, information on the currently available backup power source and its capacity, which is included in an alert sent from the base station that has lost power.

[0060] In step S42, the operation control unit 12 acquires the importance map stored in the importance map storage device 2 via the coverage information management unit 13 and supplies it to the coverage prediction unit 14. The importance map is a map that associates the importance of coverage compensation in the event of a power loss with geographical coordinates, and the importance value is defined as a function of the point coordinates (two-dimensional coordinates). When predicting the coverage compensation rate for the sector group of the backup power-driven base station to be predicted, the coverage prediction unit 14 weights it with the importance defined in the corresponding importance map.

[0061] The coverage information management unit 13 may predefine the importance map by associating importance with each point coordinate in advance based on information such as evacuation sites designated on a hazard map, topography, altitude, transportation hubs, and radio wave conditions and roaming conditions of other carriers. The importance map may, for example, define importance as a function of time, and may be predefined so that the importance varies over time according to the elapsed time since the occurrence of the disaster, the time period, or the day of the week, or may be configured so that the importance is updated.

[0062] FIG. 9A is a schematic diagram illustrating an example of a state in which the importance of each location is defined in an importance map stored in an importance map storage device 2 according to an embodiment of the present disclosure. Referring to FIG. 9A , an importance map 91 shows multiple locations arranged on a two-dimensional coordinate system along with their importance. Each location is assigned a shade ranging from 0.0 to 4.0 in importance indicated on an importance scale 92, with locations of higher importance being displayed in a darker color. While FIG. 9A shows the importance of each location arranged on a two-dimensional coordinate system discretely for ease of explanation, the importance map is not limited thereto. The importance map may be configured to allow the importance gradient to be continuously grasped on a two-dimensional coordinate system by increasing the number of locations sampled to increase the granularity of the importance map or by interpolating the importance between locations (see FIG. 10 ).

[0063] 9B is a schematic diagram illustrating an example of a state in which a coverage loss area and a coverage compensation area by a backup power base station are mapped on the importance map of FIG. 9A. Referring to FIG. 9B, a coverage compensation area 93 composed of a group of sectors of backup power base stations 66a, 66e, and 66f located in the coverage loss area 67 is shown superimposed on the uncompensated area 67. Note that in FIG. 9B, for simplicity of explanation, the coverage loss area 67 of FIG. 6B is shown as an uncompensated area, but the uncompensated area may be the uncompensated area 75 of FIG. 7B after the first coverage compensation process is performed. Points 94a, 94d, 94e, 94f, 94g, and 94h located within the uncompensated area 67 are assigned a higher importance, and coverage is compensated by the coverage compensation area 93, enabling UEs within the coverage compensation area 93 to continue communication. On the other hand, points 94b and 94c located in uncompensated area 67 are outside coverage compensation area 93, and therefore UEs near these points cannot continue communication at this point.

[0064] FIG. 10 is a schematic diagram illustrating an example of a state in which the importance gradient is continuously defined in the importance map of FIG. 9B . Referring to FIG. 10 , the importance map 91a is a heat map in which the importance gradient indicated by the importance scale 92 is continuously displayed on a two-dimensional coordinate system. The importance assigned to each point on the importance map 91a is assumed to be the same as that in FIG. 9A . It can be seen that the coverage compensation area 93 superimposed on the uncompensated area 67 compensates for the coverage of areas with darker colors assigned with higher importance. In this embodiment, the coverage compensation rate of the sector group of the backup power supply-driven base station is predicted by weighting the point coordinates defined in the importance map 91a by the importance assigned thereto. Therefore, coverage of points and areas where it is more important to continue communication even during a disaster or the like is compensated with higher priority.

[0065] Factors determining the importance may include attributes of the facility, such as population density, topography, altitude, and whether it is an important facility (e.g., evacuation shelter, train station, hospital, etc.). For example, a higher importance may be assigned to a location with a high population density or an important facility. For example, the highest importance may be assigned to a life-saving facility such as a hospital so that coverage is always guaranteed. The importance may also be changed as a function of time, depending on the passage of time or the time of day. For example, if it is expected that the population density of an evacuation shelter will be higher at night than during the day, the importance to be assigned to the evacuation shelter at night may be increased. For example, if the disaster is a tsunami and it is expected that people will move from low to high ground over time, the importance to be assigned to high ground may be increased over time. For example, the distribution of the number of users by time may be predicted from statistics of past data, and the importance may be changed according to changes in the predicted distribution of the number of users.

[0066] Furthermore, whether coverage is guaranteed by another communication carrier may be used as a factor of importance. For example, if it is predicted that coverage will be guaranteed by another communication carrier based on the radio wave conditions, coverage status, whether the communication terminal is within a roaming area, etc. of the other communication carrier, the importance may be lowered. The coverage information management unit 13 may update the importance defined in the importance maps 91, 91 a in real time in accordance with fluctuations in the above factors.

[0067] Returning to FIG. 8 , in steps S43 to S46, the operation control unit 12 of the base station operation control device 1 controls the coverage prediction unit 14 to predict a coverage compensation rate for each of a plurality of sector groups of the backup power base station, and determines a plurality of sector groups to be simultaneously operated based on the predicted coverage compensation rates. First, in step S43, the coverage prediction unit 14 creates a plurality of sector groups by combining x elements (x = 1, 2, 3, ...) from all sectors of the backup power-capable base station extracted in step S41. The initial value of the sector included in each sector group is 1 (x = 1). The coverage prediction unit 14 predicts a coverage compensation rate for each of these plurality of sector groups.

[0068] In step S44, the coverage prediction unit 14 sets parameters such as transmit power density, tilt, and azimuth for each of the multiple sector groups. In step S45, the coverage prediction unit 15 calculates a coverage compensation rate for each of the multiple sector groups for which parameters were set in step S44, using an evaluation function to which the importance maps 91, 91a acquired in step S42 are applied. Specifically, the coverage prediction unit 14 predicts coverage using the coverage compensation rate, which is the output of the evaluation function shown in the following equation 2. The evaluation function shown in equation 2 has a denominator that is the surface integral value of the importance of the entire lost coverage that is the target of coverage compensation, and a numerator that is the surface integral value of the importance of the coverage compensated by the backup power supply driven base station.

[0069]

[0070] Here, x and y are two-dimensional point coordinates, t is a time variable, and v is the importance value for each point coordinate defined in the importance map. i indicates the label of a certain sector group that is the target of score evaluation, and C all indicates the label of the sector group consisting of all sectors under control, and S Ci is sector group C i indicates the coverage range spanned by S Call is all the control target sectors C all This indicates the range of the coverage area defined by the above equation that overlaps with the compensation target area. As can be seen from equation 2, the coverage prediction unit 14 calculates the coverage compensation rate score by weighting each of the multiple sector groups by the importance defined in the importance maps 91, 91a. The coverage prediction unit 14 repeatedly calculates the coverage compensation rate score for all combinations of sectors of the standby power supply driven base station extracted in step S43. The evaluation function used by the coverage prediction unit 14 may be applied by superimposing multiple importance maps 91, 91a, as shown in equation 3.

[0071]

[0072] Here, j represents each importance map 91, 91a. In Equation 3, a weight w, which may be different for each of the multiple importance maps 91, 91a, is assigned to the surface integral value. For example, the coverage prediction unit 14 may calculate the coverage compensation rate score by superimposing a topography- or base-based importance map and an importance map based on the coverage of other carriers or roaming situations with different weightings. For example, an area with coverage of other carriers may be excluded from coverage compensation by the base station operation control device 1 according to this embodiment by assigning the smallest importance value to the area.

[0073] In step S46, the coverage prediction unit 14 determines the multiple sector groups whose coverage ratios are equal to or greater than a predetermined threshold as the multiple sector groups to be simultaneously operated. The predetermined threshold compared with the coverage compensation rate score in step S46 is the ratio of the compensated coverage area to the coverage area when all operational base stations are operated under normal circumstances, and may be, for example, 90%, but is not limited to this. The predetermined threshold may be set in advance in the coverage prediction unit 14 as the minimum coverage compensation rate to be guaranteed as an operational condition in an emergency. The predetermined threshold may vary depending on the time elapsed since the power loss and the nature of the disaster that caused the power loss. In addition to comparing the coverage ratio with the predetermined threshold, the coverage prediction unit 14 may determine the multiple sector groups to be simultaneously operated, for example, on the condition that the most important location or area assigned the highest importance on the importance map 91, 91a is 100% covered.

[0074] In the list of multiple sector groups to be operated simultaneously determined as described above, the multiple sector groups for which a coverage compensation rate equal to or greater than a predetermined threshold is calculated are arranged in order from the sector group with the smallest number of sectors. Therefore, the sector group with the smallest number of sectors is given priority in scheduling operations for coverage compensation in the uncompensated area 67. This allows communication services to be continued for a longer period with less power consumption.

[0075] The coverage prediction unit 14 may sort the multiple sector groups for which a coverage compensation rate equal to or greater than a predetermined threshold is calculated in descending order, starting with the sector group with the highest coverage compensation rate score. The coverage prediction unit 14 may also sort the multiple sector groups for which a coverage compensation rate equal to or greater than a predetermined threshold is calculated in ascending order of overlap area, starting with the sector group with the smallest overlap area among the multiple sectors included in the sector group. This allows sector groups with smaller overlap areas to be preferentially scheduled for simultaneous operation, thereby reducing power consumption and increasing the coverage compensation rate of the sector groups. The coverage prediction unit 14 may also perform this sorting within a range of multiple sector groups with the same number of sectors. However, if there is only one sector group for which a coverage compensation rate equal to or greater than a predetermined threshold is calculated, that sector group may be used to compensate for the coverage of the uncompensated area 67, or the threshold may be lowered to adjust the selection of multiple sector groups. Furthermore, the number of sectors included in one sector group may be one as described above, or may be multiple.

[0076] In step S47, the operation scheduler 15 generates an operation schedule for each of the multiple sector groups to be simultaneously operated, which was determined by the coverage prediction unit 14 in step S46. The operation schedule for the multiple sector groups generated by the operation scheduler 15 may include the on / off switch for radio wave emission, the transmit power density, the tilt, the azimuth, and the operating time of each sector of each sector group. Regarding the transmit power density, when the transmit power is constant, the transmit power density may be increased by narrowing the used bandwidth to extend the reach of the radio waves. Alternatively, the transmit power density may be increased by increasing the transmit power value. The operating time of each sector group may be determined by taking the maximum operable time of the base station with the smallest backup power capacity among the base stations constituting the sector group. When determining the multiple sector groups to be simultaneously operated, the sectors belonging to the sector group may be required to have the same backup power capacity.

[0077] The operation scheduler 15 may also assign multiple network slices to the operation schedule so that the nature of mobile communications mediated by the base station varies depending on the time elapsed since the occurrence of the disaster that caused the power loss. For example, immediately after the occurrence of a disaster, slices that can maximize the number of calls may be preferentially assigned to process reports from many users, automatic reports and alerts from each communication node, wide-area broadcasts during evacuation, user location confirmation, and disaster information confirmation. Thereafter, as time passes, the operation scheduler 15 may preferentially assign slices with low latency to facilitate communication between various parties for rescue operations.

[0078] 11A to 11C are schematic diagrams illustrating the transition of a state in which coverage of a coverage-loss area is compensated for by a backup power base station. Referring to Fig. 11A, in a first stage of base station operation rotation, a first coverage compensation area 93a (shown by diagonal lines) composed of sectors of backup power base stations 66a, 66e, and 66f toward the center of the uncompensated area 67 overlaps with the uncompensated area 67. Referring to Fig. 11B, in a second stage of base station operation rotation, a second coverage compensation area 93b (shown by diagonal lines) composed of sectors of backup power base stations 66b, 66c, and 66g toward the center of the uncompensated area 67 overlaps with the uncompensated area 67. Referring to Fig. 11C, in a third stage of base station operation rotation, a third coverage compensation area 93c (shown by diagonal lines) composed of sectors of backup power base station 66d overlaps with the uncompensated area 67. As is clear from Figures 11A to 11C, a single base station operation schedule does not necessarily fully compensate for the coverage of the uncompensated area 67, but by rotating the three operation schedules, the coverage of the uncompensated area 67 is almost entirely compensated for.

[0079] In step S48, the base station setting unit 16 transmits the operation schedule and setting parameters of the multiple sector groups scheduled in step S47 to each of the backup power base stations having the sectors to be set. The base station setting unit 16 may transmit the operation schedule and setting parameters via the VNF 22 corresponding to the target backup power base station.

[0080] As described above, in this embodiment, instead of maximizing coverage in the uncompensated area 67 with a single backup power base station or a single sector group, an operation schedule is set for each of multiple sector groups and these operation schedules are rotated over time. This allows the backup power base station with limited backup power capacity to compensate for the coverage of the uncompensated area 67 for a longer period with lower power consumption, thereby enabling communication services to be provided for a longer period.

[0081] <Communication Sequence Between the Base Station Operation Control Device and Each Base Station> FIG. 12 is a sequence diagram showing an example of a communication sequence for base station operation control processing when a power supply is lost between the base station operation control device 1 according to an embodiment of the present disclosure and a base station site. In step S121, the operation control unit 12 of the base station operation control device 1 instructs the monitoring unit 11 to monitor for an alert transmission from the affected base station site 17. In step S122, the monitoring unit 11 monitors the status of each of the base station sites 17 and 18 in accordance with the instruction from the operation control unit 12 in step S121. In step S123, when a disaster occurs, the affected base station site 18 transmits an alert to the monitoring unit 11 notifying the loss of power. For ease of explanation, it is assumed that the base station site 17 is a site of an adjacent healthy base station capable of performing first coverage compensation, and the base station site 18 is a site of a backup power supply-driven base station capable of performing second coverage compensation.

[0082] In step S124, the monitoring unit 11 sends a query to the affected base station site 18 to check the status of the affected base station site 18. This status check includes checking whether the affected base station site 18 can be powered by a battery. Here, as an example, it is assumed that the backup power source is a battery. In step S125, the monitoring unit 11 notifies the operation control unit 12 of the results of the status check of the affected base station site 18 in step S124 using a damaged site detection alert. In step S126, the operation control unit 12 instructs the monitoring unit 11 to check the damage status of base station sites surrounding the affected base station site 18.

[0083] In step S127, the monitoring unit 11 notifies the operation control unit 12 of a list of base station sites affected by the disaster in the vicinity of the affected base station site 18, based on responses to alerts and queries from base station sites in the vicinity of the affected base station site 18. In step S128, the operation control unit 12 groups the base station sites notified by the monitoring unit 11 in steps S125 and S127. In step S129, the operation control unit 12 accesses the base station information storage device 3 via the coverage information management unit 13, searches for information on base station sites adjacent to the grouped affected base station sites, and in step S130, acquires information on the base station sites adjacent to the affected base station sites.

[0084] In step S131, the operation control unit 12 instructs the coverage prediction unit 14 to calculate a compensation rate for coverage lost due to loss of power caused by the disaster. The instruction issued by the operation control unit 12 to the coverage prediction unit 14 in step S131 may be an instruction to cause the coverage prediction unit 14 to calculate a coverage compensation rate to be compensated by healthy base station sites 17 adjacent to the disaster-stricken base station site 18. The operation control unit 12 may instruct the coverage prediction unit 14 to calculate a coverage compensation rate by battery-powered base station sites, provided that coverage compensation by healthy base station sites 17 adjacent to the disaster-stricken base station site 18 leaves an uncompensated area.

[0085] In step S132, the coverage prediction unit 14 calculates the setting parameters (transmission power density, tilt, azimuth, etc. for each sector) of the adjacent healthy base station site 17 that will compensate for the lost coverage to the maximum extent possible. In step S133, the coverage prediction unit 14 notifies the operation control unit 12 of the calculated setting parameters of the adjacent healthy base station site 17 and the predicted coverage compensation rate data. In step S134, the operation control unit 12 references the coverage compensation rate data notified by the coverage prediction unit 14 in step S133, and if it determines that an uncompensated area will remain in the coverage loss area caused by the disaster, it instructs the operation scheduler 15 to create an operation schedule for the battery-powered base station site 18.

[0086] In step S135, the coverage prediction unit 14 and the operation scheduler 15 cooperate to determine setting values ​​for the battery-powered base station site 18 and create an operation schedule for the battery-powered base station site 18. In step S136, when determining the setting values ​​for the battery-powered base station site 18 and creating the operation schedule, the coverage prediction unit 14 accesses the importance map storage device 2 via the coverage information management unit 13, applies the importance maps 91, 91a corresponding to the coverage loss areas (uncompensated areas), and calculates the coverage compensation rate by weighting with the importance defined in the importance maps 91, 91a. In step S137, the operation scheduler 15 and the coverage prediction unit 14 transmit the determined setting parameters and operation schedule for the battery-powered base station site 18 to the operation control unit 12.

[0087] In step S138, the operation control unit 12 notifies the base station setting unit 16 of the setting parameters of the adjacent healthy base station site 17 received in step S133, and the setting parameters and operation schedule of the battery-powered base station site 18 received in step S137. In step S139, the base station setting unit 16 transmits the setting parameters of the adjacent healthy base station site 17 received in step S138 to the target adjacent healthy base station site 17. In step S140, the base station setting unit 16 transmits the setting parameters and operation schedule of the battery-powered base station site 18 received in step S138 to the target battery-powered base station site 18.

[0088] As described above, according to this embodiment, the base station operation control device extracts one or more base stations that can be operated by a backup power source from among the base stations for which coverage loss has been detected, predicts the coverage of the area that the base station for which coverage loss has been detected should cover for each of multiple sector groups composed of the sectors of one or more base stations, and schedules the operation of each of the multiple sector groups based on the predicted coverage. Furthermore, when predicting the coverage of each of the multiple sector groups, the base station operation control device applies an importance map that associates the importance of the area for which coverage loss occurs with geographical coordinates. This allows the provision of communication services during coverage loss to be extended for a longer period, contributing to improved communication availability.

[0089] <Hardware Configuration of Base Station Operation Control Device> Figure 13 shows a non-limiting example of the hardware configuration of a base station operation control device 1 according to an embodiment of the present disclosure. The base station operation control device 1 according to this embodiment can be implemented on a single or multiple computers or any other processing platform. As shown in Figure 13, the base station operation control device 1 includes a processor 131, a memory 132, a storage unit 133, an input unit 134, an output unit 135, a communication interface 136, and a bus 137.

[0090] As used herein, processor 131 refers to any type of computing circuitry that may include hardware and software elements. Processor 131 may be embodied as a multi-core processor, a single-core processor, a combination of one or more multi-core processors, a combination of one or more single-core processors, or a combination of one or more multi-core processors and one or more single-core processors, or may be embodied as a distributed processing system. Processor 131 may also be a central processing unit (CPU), a graphics processing unit (GPU), an high-speed processing unit (APU), an application-specific integrated circuit (ASIC), or other type of processing unit.

[0091] Memory 132 includes a non-transitory computer-readable medium. Memory 132 may include random access memory (RAM), read-only memory (ROM), other types of dynamic or static storage devices (e.g., flash memory, magnetic memory, optical memory, or a combination of at least two thereof) or a combination of at least two thereof, that store information, instructions, or both used by processor 131. Memory 132 includes machine-readable instructions executable by processor 131. These machine-readable instructions, when executed by processor 131, cause processor 131 to perform one or more of the method steps of the above-described embodiments.

[0092] The storage unit 133 stores information, software, or both related to the operation and use of the base station operation control device 1. The storage unit 133 may include, for example, a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optical disk, a solid-state disk, or a combination of at least two thereof), a compact disc (CD), a digital versatile disc (DVD), a floppy disk, a cartridge, a magnetic tape, other types of non-transitory computer-readable media, or a combination of at least two thereof, along with a corresponding drive.

[0093] The input unit 134 is configured to accept information such as user input. The input unit 134 may include, but is not limited to, a touchscreen display, a keyboard, a keypad, a mouse, a button, a switch, a microphone, or a combination of at least two thereof. Additionally or alternatively, the input unit 134 may include a sensor for detecting information (e.g., a global positioning system (GPS), an accelerometer, a gyroscope, an actuator, or a combination of at least two thereof).

[0094] The output unit 135 is configured to provide output information from the base station operation control device 1. The output unit 135 may be, for example, but is not limited to, a display, a speaker, a command device for an external device, one or more light-emitting diodes (LEDs), or a combination of at least two thereof.

[0095] The communication interface 136 is an interface that provides a communication connection with other devices such as external devices and internal devices. The connection via the communication interface 136 may be a wired connection, a wireless connection, or a combination of a wired connection and a wireless connection, and may be a direct connection or an indirect connection via a communication network that exists between the base station operation control device 1 and other devices. In other words, the standard of the communication interface 136 is not limited.

[0096] The bus 137 interconnects the processor 131, memory 132, storage unit 133, input unit 134, output unit 135, and communication interface 136 of the base station operation control device 1. The bus 137 may include wired interconnection or wireless interconnection.

[0097] The number and arrangement of components shown in Figure 13 are provided as an example. In practice, the base station operation controller 1 may include additional components, fewer components, different components, or components arranged differently than those shown in Figure 13. Additionally or alternatively, a set of components (e.g., one or more components) of the base station operation controller 1 may perform one or more functions described as being performed by another set of components of the base station operation controller 1. Furthermore, one or more method steps described in any embodiment may be performed using multiple base station operation controllers 1 in communication with each other.

[0098] Although specific embodiments have been described above, these embodiments are merely examples and are not intended to limit the scope of the present invention. The devices and methods described herein may be embodied in forms other than those described above. Furthermore, appropriate omissions, substitutions, and modifications may be made to the above-described embodiments without departing from the scope of the present invention. Such omissions, substitutions, and modifications are included within the scope of the claims and their equivalents, and belong to the technical scope of the present invention.

[0099] (Embodiments of the Present Disclosure) The present disclosure includes the following embodiments: [1] An information processing device that executes a first extraction process that extracts one or more base stations that can be driven by a backup power source from among base stations for which a coverage loss has been detected, an acquisition process that acquires an importance map that associates importance at the time of coverage loss with geographical coordinates, a prediction process that configures a plurality of sector groups from sectors of the one or more base stations and weights each of the plurality of sector groups by an importance defined in the importance map to predict coverage for a coverage loss area that should be covered by the base station for which the coverage loss has been detected, and a scheduling process that schedules operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

[0100] [2] The information processing device according to [1], characterized in that the scheduling process schedules the operation by giving priority to a sector group having a smaller number of sectors among the plurality of sector groups.

[0101] [3] The information processing device according to [1] or [2], characterized in that the scheduling process schedules the operation by giving priority to a sector group among the plurality of sector groups that has a smaller overlapping area between the coverage areas of the plurality of sectors included in one sector group.

[0102] [4] An information processing device according to any one of [1] to [3], characterized in that the importance map defines the importance to be associated with geographical coordinates so that it varies over time as a function of time.

[0103] [5] An information processing device described in any of [1] to [4], characterized in that the importance map defines the importance based on at least one of facility attributes, population density, topography, and altitude for geographical coordinates.

[0104] [6] The information processing device described in any one of [1] to [5], characterized in that the prediction process sets a transmission power density for each of the plurality of sector groups and predicts the coverage based on the set transmission power density.

[0105] [7] The information processing device described in [6], characterized in that the prediction process further sets the transmission power density by narrowing the usage bandwidth of each of the plurality of sector groups to increase the transmission power density.

[0106] [8] The information processing device described in [6] or [7], characterized in that the prediction process sets at least one of the tilt and azimuth for each of the plurality of sector groups, and predicts the coverage based on the set tilt or azimuth.

[0107] [9] An information processing device described in any one of [1] to [8], characterized in that the prediction process predicts the coverage by calculating an area ratio weighted by the importance of the area covered by each of the sector groups to the coverage loss area.

[0108]

[10] The information processing device described in any one of [1] to [9], characterized in that the scheduling process schedules the operation for a group of sectors among the group of sectors whose predicted coverage is equal to or greater than a predetermined threshold.

[0109]

[11] An information processing device described in any one of [1] to

[10] , further comprising: a second extraction process for extracting one or more base stations that are adjacent to the base station where coverage loss has been detected and for which coverage is maintained; and a setting process for selecting one or more sectors of the one or more base stations that are directed to the base station where the coverage transmission has been detected, and setting the transmission power density of the selected one or more sectors to compensate for the coverage loss.

[0110]

[12] The information processing device described in

[11] is characterized in that, after executing the second extraction process and the setting process, if there is an area where the coverage loss is not compensated, the information processing device executes the first extraction process, the acquisition process, the prediction process, and the scheduling process.

[0111]

[13] An information processing method executed by an information processing device, comprising: extracting one or more base stations that can be driven by a backup power source from among base stations in which coverage loss has been detected; obtaining an importance map that associates importance at the time of coverage loss with geographical coordinates; configuring a plurality of sector groups from the sectors of the one or more base stations; weighting each of the plurality of sector groups by an importance defined in the importance map; predicting coverage for a coverage loss area that should be covered by the base station in which coverage loss has been detected; and scheduling operation of each of the plurality of sector groups to compensate for the coverage loss area based on the predicted coverage.

[0112]

[14] An information processing system comprising: a first extraction process for extracting one or more base stations that can be driven by a standby power source from among base stations for which coverage loss has been detected; an acquisition process for acquiring an importance map that associates importance at the time of coverage loss with geographical coordinates; a prediction process for forming a plurality of sector groups from the sectors of the one or more base stations, weighting each of the plurality of sector groups by an importance defined in the importance map, and predicting coverage for a coverage loss area that should be covered by the base station for which coverage loss has been detected; and a scheduling process for scheduling operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

[0113] 1: Base station operation control device, 2: Importance map storage device, 3: Base station information storage device, 11: Monitoring unit, 12: Operation control unit, 13: Coverage information management unit, 14: Coverage prediction unit, 15: Operation scheduler, 16: Base station setting unit, 21: NFVI, 22: VNF, 24: OSS / BSS, 23: MANO, 101a, 101b: Base station site, 102a, 102b: UE, 103: RAN, 104a, 104b: Backhaul network, 105: Core network, 106: Internet, 107: PSTN, 131: Processor, 132: Memory, 133: Storage unit, 134: Input unit, 135: Output unit, 136: Communication interface, 137: Bus, 231: VIM, 232: VNFM, 233: NFVO

Claims

1. An information processing device that executes the following steps: a first extraction process that extracts one or more base stations that can be driven by a backup power source from among base stations for which a coverage loss has been detected; an acquisition process that acquires an importance map that associates importance at the time of coverage loss with geographical coordinates; a prediction process that forms a plurality of sector groups from the sectors of the one or more base stations, weights each of the plurality of sector groups by an importance defined in the importance map, and predicts coverage for a coverage loss area that should be covered by the base station for which the coverage loss has been detected; and a scheduling process that schedules operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

2. The information processing device according to claim 1, wherein the scheduling process schedules the operation by giving priority to a sector group having a smaller number of sectors among the plurality of sector groups.

3. The information processing device according to claim 1, characterized in that the scheduling process schedules the operation by giving priority to a sector group among the plurality of sector groups in which the overlapping area between the coverage areas of the plurality of sectors included in one sector group is smaller.

4. The information processing device according to claim 1, wherein the importance map defines the importance to be associated with geographical coordinates so that the importance varies over time as a function of time.

5. The information processing device according to claim 1, wherein the importance map defines the importance based on at least one of facility attributes, population density, topography, and altitude with respect to geographic coordinates.

6. The information processing device according to claim 1, characterized in that the prediction process sets a transmission power density for each of the plurality of sector groups, and predicts the coverage based on the set transmission power densities.

7. The information processing device according to claim 6, wherein the prediction process further sets the transmission power density by narrowing the bandwidth used by each of the plurality of sector groups to increase the transmission power density.

8. The information processing device according to claim 6, characterized in that the prediction process sets at least one of a tilt and an azimuth for each of the plurality of sector groups, and predicts the coverage based on the set tilt or azimuth.

9. The information processing device according to claim 1, characterized in that the prediction process predicts the coverage by calculating an area ratio weighted by the importance of the area covered by each of the sector groups to the coverage loss area.

10. The information processing device according to claim 1, wherein the scheduling process schedules the operation for a group of sectors whose predicted coverage is equal to or greater than a predetermined threshold.

11. The information processing device according to claim 1, further comprising: a second extraction process for extracting one or more base stations that are adjacent to the base station where coverage loss has been detected and for which coverage is maintained; and a setting process for selecting, from among the sectors of the one or more base stations, one or more sectors directed toward the base station where the coverage transmission has been detected, and setting the transmission power density of the selected one or more sectors so as to compensate for the coverage loss.

12. The information processing device according to claim 11, characterized in that, after executing the second extraction process and the setting process, if there is an area in which the coverage loss is not compensated, the information processing device executes the first extraction process, the acquisition process, the prediction process, and the scheduling process.

13. An information processing method executed by an information processing device, comprising: extracting one or more base stations that can be driven by a backup power source from among base stations in which coverage loss has been detected; obtaining an importance map that associates importance at the time of coverage loss with geographical coordinates; forming a plurality of sector groups from the sectors of the one or more base stations; weighting each of the plurality of sector groups by the importance specified in the importance map; predicting coverage for a coverage loss area that should be covered by the base station in which coverage loss has been detected; and scheduling operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

14. An information processing system comprising: a first extraction process for extracting one or more base stations that can be driven by a backup power source from among base stations for which a coverage loss has been detected; an acquisition process for acquiring an importance map that associates importance at the time of coverage loss with geographical coordinates; a prediction process for forming a plurality of sector groups from the sectors of the one or more base stations and weighting each of the plurality of sector groups by an importance defined in the importance map to predict coverage for a coverage loss area that should be covered by the base station for which the coverage loss has been detected; and a scheduling process for scheduling operation of each of the plurality of sector groups to compensate for the coverage for the coverage loss area based on the predicted coverage.

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