Communication control device, communication control method, communication control program product

Abstract

The communication control device (3) includes a first paging control section (309) that causes one of a ground base station provided on the ground and a non-ground base station in flight to transmit a first paging signal to a communication device (2E, 2F, 2G, 2H) within a location registration area (TA#1) including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground, and a second paging control section (310) that causes the other of the ground base station and the non-ground base station to transmit a second paging signal for the communication device (2E, 2F, 2G, 2H) in the absence of a response to the first paging signal from the communication device (2E, 2F, 2G, 2H) (Fig. 5).

Description

Technical Field

[0001] This invention relates to communication control technology in communication systems. Background Technology

[0002] The number, types, and applications of wireless communication devices, represented by smartphones and IoT (Internet of Things) devices, are constantly increasing, and wireless communication standards are continuously expanding and improving. For example, commercial services of the fifth-generation mobile communication system, widely known as "5G," began in 2018, and the standardization is still being promoted by 3GPP (Third Generation Partnership Project). Furthermore, as the next-generation wireless communication standard after 5G, efforts have begun to develop standards for "6G," or the sixth-generation mobile communication system.

[0003] Mobile communication networks (hereinafter also called mobile communication networks) for mobile devices such as smartphones and mobile phones (hereinafter collectively referred to as communication devices) are typically constructed from communication cells (hereinafter also referred to as terrestrial communication cells) provided by ground-based base stations (hereinafter also referred to as ground base stations). However, due to various reasons, it is difficult to set up a sufficient number of ground base stations in some areas, resulting in a relatively lower quality of mobile communication.

[0004] To address the issue of varying mobile communication quality due to regional factors, and the so-called "out-of-service area" problem where communication equipment in some regions cannot conduct mobile communication, research on Non-Terrestrial Networks (NTNs) is underway. In NTNs, communication satellites and unmanned aerial vehicles (UAVs) flying in space, the stratosphere, or other atmospheric layers act as base stations (hereinafter also referred to as non-terrestrial base stations; specifically, communication satellites are also called satellite base stations), providing communication cells to the ground (hereinafter also referred to as non-terrestrial communication cells; specifically, communication cells provided by communication satellites are also called satellite communication cells). Communication equipment located within a non-terrestrial communication cell communicates directly or indirectly with the non-terrestrial base station via other communication equipment. By providing non-terrestrial communication cells to areas lacking terrestrial communication cells, the quality of mobile communication in those areas can be improved.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent document 1: Japanese Patent Application Publication No. 2010-278886. Summary of the Invention

[0008] The problem the invention aims to solve

[0009] In mobile communication systems, location registration areas or tracking areas (TAs) are configured to track or detect the approximate location of communication devices. A location registration area is defined as the entire area comprised of one or more base stations, whose communication cells to the ground are combined. For example, a certain mobile network operator (MNO) in Japan covers the entire country through dozens of location registration areas.

[0010] Generally, when making a call or sending a short message to a communication device within a location registration area, all base stations within that area simultaneously send paging signals to call that communication device. Because both terrestrial and non-terrestrial base stations send paging signals simultaneously to call communication devices within the location registration area (including both terrestrial and non-terrestrial communication cells), the network load for sending paging signals increases.

[0011] The present invention was made in view of this situation, and its object is to provide a communication control device, etc., capable of efficiently sending paging signals to communication devices within a location registration area including both terrestrial communication cells and non-terrestrial communication cells.

[0012] Solution for solving the problem

[0013] To address the aforementioned problems, some aspects of the communication control apparatus of the present invention include: a first paging control unit that causes a first paging signal to be transmitted from one of a ground base station located on the ground and a non-ground base station in flight to a communication device within a location registration area including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground; and a second paging control unit that, in the absence of a response to the first paging signal from the communication device, causes a second paging signal to be transmitted from the other of the ground base station and the non-ground base station to the communication device.

[0014] According to this method, by using a first paging control unit to send a first paging signal from one of the ground base stations and non-ground base stations to communication equipment within a location registration area including both ground communication cells and non-ground communication cells, the network load for sending the paging signal can be reduced.

[0015] Another aspect of the present invention is a communication control method. The method includes: a first paging control step, causing a first paging signal to be transmitted from one of a ground-based base station and a flying non-ground base station to a communication device within a location registration area including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground; and a second paging control step, causing a second paging signal to be transmitted from the other of the ground base station and non-ground base stations to the communication device if there is no response to the first paging signal from the communication device.

[0016] Furthermore, any combination of the above-mentioned constituent elements, and the conversion of the expression of the present invention between methods, apparatus, systems, recording media, computer programs, etc., are also valid ways of presenting the present invention.

[0017] Invention Effects

[0018] According to the present invention, paging signals can be efficiently transmitted to communication devices within a location registration area that includes both terrestrial communication cells and non-terrestrial communication cells. Attached Figure Description

[0019] Figure 1 An outline of a wireless communication system with applicable communication control devices is schematically shown.

[0020] Figure 2 An example of a location registration area consisting of terrestrial communication cells and non-terrestrial communication cells is illustrated schematically.

[0021] Figure 3 This is a functional block diagram of the communication control device involved in the first embodiment.

[0022] Figure 4 This is a flowchart illustrating the communication control processing of the communication control device according to the first embodiment.

[0023] Figure 5 This is a functional block diagram of the communication control device according to the second embodiment.

[0024] Figure 6 This is a functional block diagram of the communication control device involved in the third embodiment.

[0025] Figure 7 This is a functional block diagram of the communication control device according to the fourth embodiment.

[0026] Figure 8 This illustration schematically shows the process by which the Communication Equipment Management Department registers and manages communication equipment in the EIR. Detailed Implementation

[0027] Figure 1A schematic diagram illustrates an outline of a wireless communication system 1 according to an embodiment of the present invention. The wireless communication system 1 includes a 5G wireless communication system 11, a 4G wireless communication system 12, and a satellite communication system 13. The 5G wireless communication system 11 uses NR (New Radio) or 5G NR (Fifth Generation New Radio) as its radio access technology (RAT) and 5GC (Fifth Generation Core) as its core network (CN), conforming to the fifth-generation mobile communication system (5G). The 4G wireless communication system 12 uses LTE (Long Term Evolution) or LTE-Advanced as its radio access technology and EPC (Evolved Packet Core) as its core network, conforming to the fourth-generation mobile communication system (4G). The satellite communication system 13 is responsible for satellite communication via communication satellite 131. Although not illustrated, the wireless communication system 1 may also include wireless communication systems of generations prior to 4G, wireless communication systems of generations after 5G (e.g., 6G), or any wireless communication system unrelated to generations, such as Wi-Fi.

[0028] The 5G wireless communication system 11 includes multiple 5G base stations 111A, 111B, and 111C (hereinafter sometimes collectively referred to as 5G base station 111). These multiple 5G base stations 111A, 111B, and 111C can communicate via 5G NR with communication devices 2A, 2B, 2C, and 2D (hereinafter sometimes collectively referred to as communication device 2) such as smartphones, which are located on the ground and are referred to as UE (User Equipment). The base station 111 in 5G is also referred to as gNodeB (gNB). The communication range or supported range of each 5G base station 111A, 111B, and 111C is called a cell, which is illustrated as 112A, 112B, and 112C (hereinafter sometimes collectively referred to as 5G cell 112).

[0029] The size of the 5G cells 112 in each 5G base station 111 is arbitrary, but generally ranges from a few meters to tens of kilometers in radius. Although there is no definitive definition, cells with a radius of a few meters to ten meters are called femto cells, those with a radius of ten meters to tens of meters are called pico cells, those with a radius of tens of meters to hundreds of meters are called micro cells, and those with a radius exceeding several hundred meters are called macro cells. In 5G, high-frequency radio waves such as millimeter waves are frequently used. Due to their high directivity, the communication distance is shortened when these waves are blocked by obstacles. Therefore, compared to 4G and previous generations, 5G tends to use smaller cells more often.

[0030] Communication device 2 is capable of 5G communication if it is located within at least one of the multiple 5G cells 112A, 112B, and 112C. In the illustrated example, communication device 2B located within 5G cells 112A and 112B can communicate with either 5G base station 111A or 111B via 5G NR. Additionally, communication device 2C located within 5G cell 112C can communicate with 5G base station 111C via 5G NR. Communication devices 2A and 2D, being located outside all 5G cells 112A, 112B, and 112C, are unable to communicate via 5G NR. 5G communication between each communication device 2 and each 5G base station 111 via 5G NR is managed by 5GC, which serves as the core network. For example, 5GC performs data exchange with each 5G base station 111, data exchange with external networks such as EPC, satellite communication system 13, and the Internet, and mobility management of communication device 2.

[0031] The 4G wireless communication system 12 includes multiple 4G base stations 121 located on the ground and capable of communicating with the communication device 2 via LTE or LTE-Advanced. Figure 1 (Only one is shown in the diagram). The 4G base station 121 is also referred to as an eNodeB (eNB). Like the 5G base stations 111, the communication range or supported range of each 4G base station 121 is also referred to as a cell and is shown as 122.

[0032] Communication device 2 can perform 4G communication when located inside 4G cell 122. In the illustrated example, communication devices 2A and 2B, located inside 4G cell 122, can communicate with 4G base station 121 via LTE or LTE-Advanced. Communication devices 2C and 2D, being located outside 4G cell 122, are unable to communicate via LTE or LTE-Advanced. 4G communication between each communication device 2 and each 4G base station 121 via LTE or LTE-Advanced is managed by the EPC, which serves as the core network. For example, the EPC performs data exchange with each 4G base station 121, data exchange with external networks such as 5GC, satellite communication system 13, and the Internet, and motion management of communication devices 2.

[0033] Note the communication devices 2A, 2B, 2C, and 2D. In the illustrated example, communication device 2A is capable of 4G communication with 4G base station 121; communication device 2B is capable of 5G communication with 5G base stations 111A and 111B, as well as 4G communication with 4G base station 121; and communication device 2C is capable of 5G communication with 5G base station 111C. When multiple base stations (111A, 111B, 121) are capable of communication, as with communication device 2B, the base station judged to be the best in terms of communication quality is selected for communication with communication device 2B under the management of the 5GC and / or EPC, which serves as the core network. Furthermore, since communication device 2D is not capable of communicating with any 5G base station 111 or 4G base station 121, it communicates via satellite communication system 13 as described below.

[0034] Satellite communication system 13 is a wireless communication system that uses a communication satellite 131, which is a low-Earth orbit satellite flying in low-Earth orbit space at an altitude of 500km to 700km above the Earth's surface, as a non-terrestrial base station. Similar to 5G base station 111 and 4G base station 121, the communication range or supported range of communication satellite 131 is also referred to as a cell and is illustrated as 132. Thus, communication satellite 131, acting as a non-terrestrial base station, provides satellite communication cell 132 as a non-terrestrial communication cell on the ground. If ground communication equipment 2 is located inside satellite communication cell 132, it can perform satellite communication. Similar to 5G base station 111 in 5G wireless communication system 11 and 4G base station 121 in 4G wireless communication system 12, communication satellite 131, acting as a base station in satellite communication system 13, can directly or indirectly communicate with communication equipment 2 within satellite communication cell 132 via aircraft or the like. The wireless access technology used by the communication satellite 131 to communicate wirelessly with the communication equipment 2 within the satellite communication cell 132 can be the same as 5G base station 111 (5G NR), or the same as 4G base station 121 (LTE or LTE-Advanced), or any other wireless access technology that the communication equipment 2 can use. Therefore, the communication equipment 2 does not need to have special functions or components for satellite communication.

[0035] Satellite communication system 13 includes gateway 133, which serves as a ground station located on the ground and capable of communicating with communication satellite 131. Gateway 133 has a satellite antenna for communicating with communication satellite 131 and is connected to 5G base station 111 and 4G base station 121, which serve as ground base stations constituting a Terrestrial Network (TN). In this manner, gateway 133 communicatively connects the NTN including communication satellite 131 and the TN including ground base stations 111 and 121. When communication satellite 131 conducts 5G communication with communication equipment 2 in satellite communication cell 132 via 5G NR, the 5GC connected via gateway 133 and 5G base station 111 (or 5G radio access network) in the TN is used as the core network. When communication satellite 131 conducts 4G communication with communication equipment 2 in satellite communication cell 132 via LTE or LTE-Advanced, the EPC connected via gateway 133 and 4G base station 121 (or 4G radio access network) in the TN is used as the core network. In this way, appropriate cooperation is achieved between different wireless communication systems such as 5G communication, 4G communication, and satellite communication via gateway 133.

[0036] Satellite communication based on communication satellite 131 is primarily used to cover areas without or with few terrestrial base stations such as 5G base station 111 or 4G base station 121. In the illustrated example, communication device 2D, located outside the communication cell of all terrestrial base stations, communicates with communication satellite 131. On the other hand, although communication devices 2A, 2B, and 2C, which are capable of good communication with any terrestrial base station, can also communicate with communication satellite 131 because they are located within satellite communication cell 132, they communicate with terrestrial base stations rather than with communication satellite 131 itself, thereby conserving the limited communication resources (including power) of communication satellite 131 for communication devices such as 2D. Communication satellite 131 uses beamforming to direct communication waves toward communication device 2D within satellite communication cell 132 to improve communication quality with communication device 2D.

[0037] The size of the satellite communication cell 132 of the communication satellite 131, which serves as a satellite base station, can be arbitrarily set according to the number of beams emitted by the communication satellite 131. For example, a satellite communication cell 132 with a diameter of approximately 24 km can be formed by combining up to 2800 beams. As shown in the figure, the satellite communication cell 132 is generally larger than a terrestrial communication cell such as a 5G cell 112 or a 4G cell 122, and may include one or more 5G cells 112 and / or 4G cells 122 within it. Furthermore, although the communication satellite 131 flying in low-Earth orbit space at an altitude of approximately 500 km to 700 km above the Earth's surface is exemplified above as a non-terrestrial base station, communication satellites flying in higher geostationary orbits or other high-Earth orbit space, or unmanned or manned aircraft flying in lower atmospheres such as the stratosphere (e.g., approximately 20 km above the Earth's surface), can also be used as non-terrestrial base stations as an addition to or alternative to the communication satellite 131.

[0038] As described above, the wireless communication system 1 according to this embodiment includes terrestrial networks (TN) 11 and 12 and a non-terrestrial network (NTN) 13. The terrestrial networks (TN) 11 and 12 are capable of communicating with communication devices 2 in terrestrial communication cells 112 and 122 provided to the ground by terrestrial base stations 111 and 121 located on the ground, and the non-terrestrial network (NTN) 13 is capable of communicating with communication devices 2 in non-terrestrial communication cells 132 provided to the ground by non-terrestrial base stations 131 in flight.

[0039] In the following text, we will refer to the following: Figure 2 The following describes several embodiments for carrying out the present invention. All or part of the structural elements of each embodiment can be arbitrarily combined as long as they do not impede the function or effect of each embodiment. Furthermore, common or identical structural elements in the multiple embodiments are given the same reference numerals, and repeated descriptions are omitted.

[0040] Figure 2 This schematically illustrates the communication between ground communication cells 112 and 122 (in... Figure 2 (marked as "TN Cell") and non-terrestrial communication cell 132 (in Figure 2 The location registration area or tracking area (marked as "NTN Cell") constitutes the location registration area or tracking area. Figure 2 Examples (marked as "TA") show that terrestrial communication cells 112 and 122 are provided to the ground by terrestrial base stations 111 and 121 located on the ground, and non-terrestrial communication cell 132 is provided to the ground by a flying non-terrestrial base station 131. The first location registration area TA1 is defined by one or more geographically adjacent or nearby (…). Figure 2The location registration area consists of multiple terrestrial communication cells 112 and 122. The second location registration area TA2 consists of one or more geographically adjacent or close terrestrial communication cells. Figure 2 The location registration area consists of one non-terrestrial communication cell (132), and the third location registration area (TA3) consists of one or more geographically adjacent or close cells. Figure 2 The location registration area consists of multiple terrestrial communication cells 112 and 122.

[0041] Each location registration area TA1 to TA3 is assigned a unique code or ID called TAC (Tracking Area Code). Figure 2 In simple terms, these are represented as "#1" to "#3". Specifically, the TAC or ID of the first location registration area TA1 is "#1", the TAC or ID of the second location registration area TA2 is "#2", and the TAC or ID of the third location registration area TA3 is "#3". However, as described later, sometimes the TAC or ID of the second location registration area TA2 is also set to the same "#1" as the first location registration area TA1. Therefore, a location registration area can include different types of communication cells (terrestrial communication cells 112, 122 and non-terrestrial communication cells 132). Figure 2 In the example, communication device 2E is located in the first location registration area TA1, communication device 2F is located in the overlapping area of ​​the first location registration area TA1 and the second location registration area TA2, communication device 2G is located in the second location registration area TA2, communication device 2H is located in the overlapping area of ​​the second location registration area TA2 and the third location registration area TA3, and communication device 2I is located in the third location registration area TA3 (hereinafter, communication devices 2E to 2I are collectively referred to as communication device 2).

[0042] Figure 3This is a functional block diagram of the communication control device 3 according to the first embodiment. The communication control device 3 includes an estimation unit 301, a connection detection unit 302, an overlapping area determination unit 303, a connection change restriction unit 304, a connection control unit 305, an area change detection unit 306, an area change notification unit 307, and a connection history information retention unit 308. These functional blocks are implemented through the cooperation of hardware resources such as the computer's central processing unit, memory, input devices, output devices, and peripheral devices connected to the computer, and the software executed using them. Regardless of the type of computer and its location, the above-mentioned functional blocks can be implemented by the hardware resources of a single computer or by combining hardware resources distributed across multiple computers. In particular, in this embodiment, some or all of the functional blocks of the communication control device 3 can be implemented in a distributed or centralized manner through communication devices 2 (2F, etc.), ground base stations 111, 121, non-ground base stations 131, and computers or processors installed in the core network CN. Figure 3 (For convenience, all these functional blocks are shown separately).

[0043] In this embodiment, a first location registration area TA1, including a terrestrial base station, and a second location registration area TA2, including a non-terrestrial base station, are assigned different TACs or IDs "#1" and "#2". That is, terrestrial communication cells provided by the terrestrial base station to the ground and non-terrestrial communication cells provided by the non-terrestrial base station to the ground belong to different location registration areas TA1 and TA2. In this case, a communication device 2F in the overlapping area OA of the first location registration area TA1 and the second location registration area TA2 can communicate with both the terrestrial base station in the first location registration area TA1 and the non-terrestrial base station in the second location registration area TA2. If the connection destination of the communication device 2F in the overlapping area OA frequently switches between the terrestrial base station and the non-terrestrial base station, the location registration area to which the communication device 2F belongs changes each time. Therefore, the area change notification unit 307, described later, will frequently issue area change notifications. The communication control device 3 according to this embodiment suppresses such frequent changes in the location registration area or area change notifications in the overlapping area OA of the terrestrial communication cell and the non-terrestrial communication cell.

[0044] The estimation unit 301 estimates the connection status (e.g., which connection it is currently made to, between a terrestrial base station and a non-terrestrial base station) and location (e.g., whether it is located within the overlapping area OA) of the communication device 2F within the overlapping area OA. The estimation unit 301 obtains information indicating the connection status and location of the communication device 2F within the overlapping area OA from the communication device 2 (2F, etc.), the terrestrial base station constituting the first location registration area TA1, the non-terrestrial base station constituting the second location registration area TA2, the core network CN, and any database 4 outside the wireless communication system 1.

[0045] For example, information indicating the connection status and location of communication device 2F within the overlapping area OA is obtained from the NWDAF (Network Data Analytics Function) or LMF (Location Management Function) in the core network CN (CN) introduced into 5G, i.e., 5GC. The NWDAF is responsible for collecting and analyzing data on the network, including 5G. Specifically, the NWDAF collects and accumulates historical activity information (including historical information related to the connection destination base station and location of the communication device 2) related to various activities performed on the network by multiple communication devices 2 connected to the network, and uses the analysis results of this information for, for example, traffic control on the network. The LMF manages the physical location of each communication device 2 on the 5G network. Furthermore, in other wireless communication systems including future generations of wireless communication systems, it is envisioned that similar functions to NWDAF and / or LMF will be provided under different names; however, in this embodiment, such similar functions can be used as a substitute for or addition to NWDAF and / or LMF.

[0046] In addition, the database 4 outside the wireless communication system 1 includes a server used by a service operator that provides map services and location tracking services to multiple communication devices 2 connected to the network. This allows for the acquisition of information indicating the location of communication devices 2F within the overlapping area OA. In these services, location data of multiple communication devices 2 connected to the network are collected and accumulated from GPS modules, etc., and based on the analysis of this data, data related to congestion conditions in different regions and time periods is generated to improve service quality.

[0047] As described above, it is possible to obtain statistical information (including statistical information related to connection destination base stations) and / or historical information related to the activities of an unspecified majority of communication devices 2 on the network, primarily from the core network CN (NWDAF, etc.) and / or database 4. Figure 3In this example, the estimation unit 301 can obtain historical activity information such as congestion status or communication traffic in each time period within the overlapping area OA and non-overlapping areas (e.g., the area where communication devices 2E or 2G are located) from the core network CN or database 4, as information to indicate the current connection status or location of communication device 2F in the overlapping area OA. For example, during the time period when the estimation unit 301 estimates the current connection status or location of communication device 2F, if the historical activity information from the core network CN or database 4 indicates that the number or traffic of communication devices 2 in the overlapping area OA is on average greater than the number or traffic of communication devices 2 in the non-overlapping area, or if most of the communication devices 2 in the overlapping area OA are connected to a ground base station, it can be estimated that the communication device 2F is likely located in the overlapping area OA and is likely connected to a ground base station (first location registration area TA1).

[0048] Furthermore, not limited to the activity history information of an unspecified number of communication devices 2 from the core network CN or database 4, when the activity history information of the communication device 2F itself, which is the object of estimation, can be obtained from the communication device 2F itself, the ground base station constituting the first location registration area TA1, the non-ground base station constituting the second location registration area TA2, the core network CN, database 4, etc., the connection status or location of the communication device 2F can be estimated with high accuracy. For example, during the time period when the estimation unit 301 estimates the current connection status or location of the communication device 2F, if the acquired activity history information indicates that the communication device 2F was in the overlapping area OA more frequently than in the non-overlapping area, and the communication device 2F in the overlapping area OA was connected to the ground base station more frequently, it can be estimated that the communication device 2F is highly likely to be in the overlapping area OA and highly likely to be connected to the ground base station (first location registration area TA1).

[0049] In addition to or as a substitute for this kind of activity history information from another day in the past, the estimation unit 301 can also use the activity history information of the communication device 2F just before (e.g., within 1 hour) before estimating the current connection status or location of the communication device 2F. For example, if the activity history information obtained within 30 minutes before the estimation unit 301 estimates the current connection status and location of the communication device 2F indicates that the communication device 2F is located in the overlapping area OA and connected to the ground base station, then it can be estimated that the probability of the communication device 2F continuing to be located in the overlapping area OA and connected to the ground base station (first location registration area TA1) is extremely high.

[0050] For the NWDAF and database 4, which primarily collect historical activity information of an unspecified majority of communication devices 2, the LMF can collect statistical information and / or historical information related to the activity of a specific communication device 2F on the network. For example, during the time period when the estimation unit 301 estimates the current connection status or location of communication device 2F, if the historical activity information obtained from the LMF indicates that communication device 2F was in the overlapping area OA more frequently than in the non-overlapping area, and that communication device 2F in the overlapping area OA was connected to a ground base station more frequently, it can be estimated that the probability of communication device 2F being in the overlapping area OA is extremely high, and the probability of it being connected to a ground base station (first location registration area TA1) is extremely high. In addition, if the historical activity information obtained from the LMF indicates that communication device 2F is located in the overlapping area OA and connected to a ground base station within 30 minutes before the estimation unit 301 estimates the current connection status and location of communication device 2F, it can be estimated that the probability of communication device 2F continuing to be located in the overlapping area OA and connected to a ground base station (first location registration area TA1) is extremely high. In addition, the estimation unit 301 can directly obtain the activity history information of the specific communication device 2F as described above from the GPS module, memory, etc. mounted on the communication device 2F, the ground base station constituting the first location registration area TA1, the non-ground base station constituting the second location registration area TA2, etc.

[0051] When the connection status of the communication device 2F, the object of estimation by the estimation unit 301, can be directly and in real-time identified from the connection control unit 305 (described later), the estimation unit 301 may not need to estimate the connection status of the communication device 2F. Similarly, when the location of the communication device 2F, the object of estimation by the estimation unit 301, can be directly and in real-time identified from a GPS module or the like mounted on the communication device 2F, the estimation unit 301 may not need to estimate the location of the communication device 2F.

[0052] The connection detection unit 302 detects whether the communication device 2F within the overlapping area OA is connected to either a ground base station constituting the first location registration area TA1 or a non-ground base station constituting the second location registration area TA2. The connection detection unit 302 can detect the base station connected to the communication device 2F within the overlapping area OA based on the connection status of the communication device 2F estimated by the estimation unit 301 or the real-time connection status of the communication device 2F identified by the connection control unit 305.

[0053] The overlapping area determination unit 303 determines the overlapping area OA of the first location registration area TA1 and the second location registration area TA2, and detects whether the communication device 2F is within the overlapping area OA. The overlapping area determination unit 303 can determine whether the communication device 2F is within the overlapping area OA based on the position of the communication device 2F estimated by the estimation unit 301 and the real-time position of the communication device 2F identified by the GPS module or the like mounted on the communication device 2F.

[0054] While the overlapping area determination unit 303 confirms that the communication device 2F is within the overlapping area OA, the connection change restriction unit 304 restricts changes to the connection destination of the communication device 2F from one of the terrestrial base stations constituting the first location registration area TA1 and the non-terrestrial base stations constituting the second location registration area TA2 to the other base station. For example, the connection change restriction unit 304 rejects at least one connection destination change request received from the communication device 2F within the overlapping area OA for a connection to the other base station. Alternatively, the connection change restriction unit 304 may also notify the communication device 2F within the overlapping area OA that the location registration area containing the other base station is a prohibited migration area.

[0055] Specifically, when communication device 2F within the overlapping area OA is connected to a ground base station constituting the first location registration area TA1, changes in the connection destination of communication device 2F to a non-ground base station constituting the second location registration area TA2 are restricted. Conversely, when communication device 2F within the overlapping area OA is connected to a non-ground base station constituting the second location registration area TA2, changes in the connection destination of communication device 2F to a ground base station constituting the first location registration area TA1 are restricted. Thus, during the period when the situation of communication device 2F being within the overlapping area OA is confirmed, changes in the base station type of the connection destination directly related to changes in the location registration area are restricted. Therefore, according to this embodiment, the frequent occurrence of changes in the location registration area within the overlapping area OA and the frequent occurrence of area change notifications by the area change notification unit 307 described later can be suppressed.

[0056] The connection control unit 305 connects each communication device 2 to each base station and changes the connection destination base station of each communication device 2 according to fluctuations in the communication quality of each base station or the movement of each communication device 2. For communication device 2F within the overlapping area OA, as mentioned above, the change of base station type within the overlapping area OA is restricted. However, in the case of extreme deterioration in the communication quality of a base station of one type currently connected within the overlapping area OA, or in the case of communication device 2F moving outside the overlapping area OA (detected by the overlapping area determination unit 303), it is allowed to change the connection destination to another type of base station.

[0057] The area change detection unit 306 detects changes in the location registration area to which each communication device 2 is connected. For example, if a communication device 2F connected to a ground base station constituting a first location registration area TA1 within an overlapping area OA moves outside the overlapping area OA and into a region outside the first location registration area TA1 but within a second location registration area TA2, the connection control unit 305 connects the communication device 2F to a non-ground base station constituting the second location registration area TA2. In this case, the location registration area of ​​the connection destination of the communication device 2F is changed from the first location registration area TA1 to the second location registration area TA2, and this is detected by the area change detection unit 306.

[0058] When the area change detection unit 306 detects a change in the location registration area of ​​the connection destination of each communication device 2, the area change notification unit 307 generates an area change notification (TA Update). The area change detection unit 306 and the area change notification unit 307 are typically located in the communication device 2F. Specifically, the communication device 2F identifies itself as connected to the second location registration area TA2 based on the TAC "#2" contained in the notification information sent by the non-terrestrial base station that the connection destination has changed. Based on the fact that the TAC "#1" is different from the TAC "#1" of the first location registration area TA1 contained in the notification information sent by the terrestrial base station that is the source of the connection change, it detects that the location registration area of ​​its connection destination has changed (area change detection unit 306). Then, the communication device 2F notifies the core network CN of the change in its connection destination location registration area in the form of an area change notification (area change notification unit 307).

[0059] When the connection destination of communication device 2F within the overlapping area OA changes from one type of base station (e.g., a terrestrial base station) to another type of base station (e.g., a non-terrestrial base station), the connection history information retention unit 308 retains the connection history information for that type of base station. Typically, the connection history information retention unit 308, provided in communication device 2F, retains the connection history information indicating that communication device 2F is connected to that type of base station for at least a predetermined time. During the period when the connection history information retention unit 308 retains the connection history information, and while the overlapping area determination unit 303 confirms that communication device 2F is within the overlapping area OA, if the connection destination of communication device 2F changes again from another type of base station to the type of base station whose connection history information is retained, the area change notification unit 307 does not generate an area change notification. For example, if the connection destination of communication device 2F in the overlapping area OA changes from a terrestrial base station to a non-terrestrial base station and then changes back to a terrestrial base station, the area change notification from the second location registration area TA2 (non-terrestrial base station) to the first location registration area TA1 (terrestrial base station) is not generated based on the connection history information maintained by the connection history information retention unit 308. Therefore, the frequent occurrence of area change notifications in the overlapping area OA can be suppressed.

[0060] Figure 4 This is a flowchart illustrating the communication control process of the communication control device 3 according to the first embodiment. In the flowchart, "S" represents a step or process. In S1, the overlapping area determination unit 303 determines the overlapping area OA of the first location registration area TA1 and the second location registration area TA2, and determines whether the communication device 2F is within the overlapping area OA. If the determination is "yes" in S1, the process proceeds to S2, where the estimation unit 301 estimates the connection status of the communication device 2F within the overlapping area OA. In S3, the connection detection unit 302, based on the connection status of the communication device 2F estimated in S2 and the real-time connection status of the communication device 2F identified by the connection control unit 305, detects whether the communication device 2F within the overlapping area OA is connected to either the ground base station constituting the first location registration area TA1 or the non-ground base station constituting the second location registration area TA2.

[0061] In S4, while confirming in S1 that the communication device 2F is within the overlapping area OA, the connection change restriction unit 304 restricts the communication device 2F from changing its connection destination from one of the ground base stations constituting the first location registration area TA1 and the non-ground base stations constituting the second location registration area TA2 to the other base station. In S5, the connection control unit 305 determines whether the connection destination base station of the communication device 2F has changed. If it is "yes" in S5, the process proceeds to S6, where the area change detection unit 306 detects a change in the location registration area to which the communication device 2F is connected, and the area change notification unit 307 generates an area change notification (TA Update). In S7, the overlapping area determination unit 303 determines whether the communication device 2F is within the overlapping area OA.

[0062] If S7 is "No", it means that the connection destination base station change occurred in S5 because the communication device 2F moved outside the overlapping area OA. If S7 is "Yes", it means that the connection destination base station change occurred in S5 while the communication device 2F remained within the overlapping area OA. In this case, in the subsequent S8, the connection history information holding unit 308 generates and holds connection history information indicating that the communication device 2F within the overlapping area OA was connected to a base station of a certain type before the connection destination change in S5. In S9, the connection control unit 305 determines whether the connection destination base station of the communication device 2F within the overlapping area OA has changed again. If S9 is "Yes", proceed to S10, but while the connection history information held by the connection history information holding unit 308 in S8 is held, the area change notification unit 307 does not generate an area change notification along with the connection destination change in S9.

[0063] Figure 5 This is a functional block diagram of the communication control device 3 according to the second embodiment. The communication control device 3 includes components similar to those in the first embodiment (…). Figure 3 The system includes the same estimation unit 301, connection detection unit 302, and overlapping area determination unit 303, and additionally includes a first paging control unit 309, a second paging control unit 310, and a base station type recording unit 311. Repeated descriptions of functional blocks common to the first embodiment are omitted.

[0064] In this embodiment, the first location registration area TA1, which includes terrestrial communication cells 112 and 122, and the second location registration area TA2, which includes non-terrestrial communication cells 132, are assigned the same TAC or ID "#1". That is, the first location registration area TA1 and the second location registration area TA2 constitute a large integrated location registration area TA0 assigned the TAC or ID "#1".

[0065] Generally, when making a call or sending a short message to a communication device within a location registration area, paging signals for that communication device are simultaneously transmitted from all base stations within that location registration area. Therefore, paging signals for communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0 are transmitted simultaneously not only from the ground base stations 111 and 121 constituting the first location registration area TA1, but also from the communication satellite 131 constituting the second location registration area TA2. The integrated location registration area TA0 is a large area containing a large number of base stations and communication devices within its service area, thus increasing the network load for transmitting paging signals. Furthermore, as mentioned earlier, communication device 2 generally preferentially connects to ground base stations 111 and 121; therefore, the probability of communication device 2 connecting to communication satellite 131 is considered relatively low in many areas. It is undesirable to waste the limited electricity generated by solar power from solar panels mounted on communication satellite 131 on transmitting paging signals with a relatively low probability of successful call transmission. The communication control device 3 according to this embodiment enables efficient transmission of paging signals to communication devices 2E, 2F, 2G and 2H within an integrated location registration area TA0, which includes at least one terrestrial communication cell and at least one non-terrestrial communication cell, respectively.

[0066] The base station estimation unit, specifically estimation unit 301, estimates the base stations connected to communication devices 2E, 2F, 2G, and 2H within the integrated location registration area (TAO). Estimation unit 301 can communicate with... Figure 3 The estimation unit 301 of the first embodiment is configured similarly. While the estimation unit 301 of the first embodiment estimates the connection status and location of communication device 2F within the overlapping area OA, the estimation unit 301 of this embodiment estimates the type of the destination base station (terrestrial base station 111, 121, or non-terrestrial base station 131), as the connection status of communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0 within the overlapping area OA is not limited to this. Furthermore, the estimation unit 301 of this embodiment can estimate other connection statuses and locations of communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0 in the same manner as in the first embodiment.

[0067] The estimation unit 301 estimates the type of base station connected to the communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0 based on at least one of the following: performance information, corresponding frequency information, subscription information, location information, communication status information, activity history information, and activity history information of an unspecified majority of communication devices 2 within the integrated location registration area TA0. This information, indicating the type of the destination base station connected to the communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0, is obtained by the estimation unit 301 from the communication device 2 itself (the object of estimation), the ground base station constituting the first location registration area TA1, the non-ground base station constituting the second location registration area TA2, the core network CN, and any database 4 outside the wireless communication system 1.

[0068] For example, the performance information, corresponding frequency information, subscription information, communication status information, and activity history information of the communication device 2 being estimated indicate whether the communication device 2 is capable of or inclined to perform terrestrial communication via ground base stations 111 and 121 and non-terrestrial communication via non-terrestrial base station 131, respectively. Therefore, it provides a useful indication related to the type of the destination base station connected to the communication device 2. In addition, based on the location information of the estimated object, i.e., the communication device 2, obtained from the LMF of the core network CN, the GPS module of the communication device 2, etc., the location of the communication device 2 within the integrated location registration area TA0 can be detected or estimated. Therefore, it is possible to estimate or determine that the destination of the communication device 2E within the first location registration area TA1 and outside the overlapping area OA is the ground base station 111 and 121, and to estimate or determine that the destination of the communication devices 2G and 2H within the second location registration area TA2 and outside the overlapping area OA is the non-terrestrial base station 131. For the communication device 2F within the overlapping area OA, similar to the first embodiment, the estimation unit 301 estimates the type of the destination base station by referring to the NWDAF of the core network CN, the activity history information of an unspecified number of communication devices 2 obtained from the database 4, etc.

[0069] The connection detection unit 302 also refers to the estimation results of the estimation unit 301 to detect the type of base station (connected to) by the communication devices 2E, 2F, 2G and 2H in the integrated location registration area TA0. The overlapping area determination unit 303 determines the overlapping area OA of the first location registration area TA1 (terrestrial communication cells 112, 122) and the second location registration area TA2 (non-terrestrial communication cell 132), and detects the communication device 2F in the overlapping area OA.

[0070] When a call and a short message are received from the core network CN for communication devices 2E, 2F, 2G, and 2H within an integrated location registration area TA0 that includes at least one terrestrial communication cell 112, 122, and at least one non-terrestrial communication cell 132, the first paging control unit 309 causes a first paging signal to be sent from a base station of one type among terrestrial base stations 111, 121 and non-terrestrial base station 131 for the communication devices 2E, 2F, 2G, and 2H.

[0071] For example, as shown in the figure, the first paging control unit 309 causes a first paging signal to be transmitted from ground base stations 111 and 121 (first location registration area TA1). This first paging signal enables normal calling of communication devices 2E, 2F, etc., connected to ground base stations 111 and 121 within the first location registration area TA1. If the call made via the first paging signal is successful, there is no need to transmit a second paging signal from the communication satellite 131, thus saving the limited power of the communication satellite 131. Furthermore, by enabling the first paging signal to be transmitted only from a portion of the base stations included in the integrated location registration area TA0, the network load for transmitting paging signals can be reduced.

[0072] The first paging control unit 309 can also transmit a first paging signal from the communication satellite 131 (second location registration area TA2), which is a non-terrestrial base station. Through this first paging signal, communication devices 2F, 2G, 2H, etc., connected to the communication satellite 131 within the second location registration area TA2 can be called normally.

[0073] Preferably, the first paging control unit 309 causes a first paging signal to be sent from a base station of the type estimated by the estimation unit 301 and / or a base station of the type detected by the connection detection unit 302. For example, when a call is made to a communication device 2E that is likely connected to ground base stations 111 and 121 because it is located within the first location registration area TA1 (terrestrial communication cells 112, 122) and outside the overlapping area OA, the first paging signal is sent from ground base stations 111 and 121. Similarly, when a call is made to communication devices 2G and 2H that are likely connected to communication satellite 131 because they are located within the second location registration area TA2 (satellite communication cell 132) and outside the overlapping area OA, the first paging signal is sent from communication satellite 131.

[0074] When a call is made to a communication device 2F located within the overlapping area OA of the first location registration area TA1 and the second location registration area TA2, the first paging signal is sent from a base station (ground base station 111, 121 or non-ground base station 131) that is highly likely to be connected to the communication device 2F, based on the estimation result of the estimation unit 301 and / or the detection result of the connection detection unit 302, after confirming by the overlapping area determination unit 303 that the communication device 2F is indeed located within the overlapping area OA. Furthermore, the first paging control unit 309 may also use the estimation result of the estimation unit 301 only when calling a communication device (such as 2F) within the overlapping area OA. This is because, as described above, for communication devices (2E, 2G, 2H, etc.) outside the overlapping area OA, as long as the location of the communication device is known via a GPS module or the like, it is clear which type of base station it is highly likely to be connected to, even without estimation.

[0075] In the absence of a response to the first paging signal from communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0, the second paging control unit 310 causes a second paging signal to be sent from another type of base station among ground base stations 111, 121 and non-ground base station 131 for the communication devices 2E, 2F, 2G, and 2H.

[0076] For example, as shown in the figure, if there is no response within a predetermined time to the first paging signal sent from ground base stations 111 and 121 (first location registration area TA1) by the first paging control unit 309, the second paging control unit 310 sends a second paging signal from the communication satellite 131 (second location registration area TA2). Through this second paging signal, communication devices 2F, 2G, 2H, etc., connected to the communication satellite 131 within the second location registration area TA2 can be called normally.

[0077] Furthermore, if there is no response within the predetermined time to the first paging signal sent from the communication satellite 131 (second location registration area TA2) by the first paging control unit 309, the second paging control unit 310 sends a second paging signal from ground base stations 111 and 121 (first location registration area TA1). Through this second paging signal, communication devices 2E, 2F, etc., connected to ground base stations 111 and 121 within the first location registration area TA1 can be called normally.

[0078] When communication devices 2E, 2F, 2G, and 2H within the integrated location registration area TA0 migrate from a communication state (also known as a connected state) to a non-communication state (also known as a waiting state), the base station type recording unit 311 obtains and records the type of the base station they were connected to before the migration from the connection detection unit 302. The first paging control unit 309 can also cause the base station of the type recorded by the base station type recording unit 311 to send a first paging signal. Since it is assumed that the communication devices 2 whose type of connection to the destination base station is recorded by the base station type recording unit 311 will remain in a state where they can connect to the base station before the migration for at least a predetermined time even after migrating to the waiting state, the success rate of calls made via the first paging signal can be improved. Alternatively, when a call occurs before a predetermined time has elapsed after the base station type recording unit 311 has recorded the call, a first paging signal is sent from a base station of the type recorded by the base station type recording unit 311. When a call occurs after a predetermined time has elapsed after the base station type recording unit 311 has recorded the call, a first paging signal is sent from a base station of the type based on the estimation result of the estimation unit 301 and / or the detection result of the connection detection unit 302.

[0079] Figure 6 This is a functional block diagram of the communication control device 3 according to the third embodiment. The communication control device 3 includes components similar to those in the first embodiment (…). Figure 3 ) and / or the second embodiment ( Figure 5 The first embodiment includes the same estimation unit 301, connection detection unit 302, overlapping area determination unit 303, and connection control unit 305, and additionally includes a connection availability determination unit 312 and a connection establishment information holding unit 313. Repeated descriptions of functional blocks common to the first and / or second embodiments are omitted.

[0080] In this embodiment, the first location registration area TA1, including terrestrial communication cells 112 and 122, and the second location registration area TA2, including non-terrestrial communication cell 132, are assigned different TACs "#1", "#2", or the same TAC "#1". That is, the first location registration area TA1 and the second location registration area TA2 can be configured as distinct location registration areas, similar to the first embodiment, or they can be configured as a large integrated location registration area, similar to the second embodiment. This embodiment relates to communication control in the overlapping area OA of terrestrial communication cells 112 and 122 (e.g., the first location registration area TA1) and non-terrestrial communication cell 132 (e.g., the second location registration area TA2), regardless of the structure of the location registration areas.

[0081] Communication device 2F within the overlapping area OA is connected to either ground base stations 111 and 121 providing terrestrial communication cells 112 and 122, or communication satellite 131 providing satellite communication cell 132. For example, communication device 2F within the overlapping area OA may be connected to ground base stations 111 and 121 but not to communication satellite 131. In this state, if the TN (terrestrial network) to which ground base stations 111 and 121 belong experiences a communication failure due to a disaster or accident, communication device 2F within the overlapping area OA, which is no longer connected to the TN, attempts to connect to the NTN (non-terrestrial network) to which communication satellite 131 belongs. This handover to the destination network generally involves confirmation of the subscription information of communication device 2F in the core network CN and the network information of the communication operator (regarding the TN, also known as the PLMN (Public Land Mobile Network) number), thus requiring time. In emergency situations such as disasters, this extended network handover time may not be permissible. The communication control device 3 involved in this embodiment shortens the network handover time in the overlapping area of ​​terrestrial communication cells and non-terrestrial communication cells.

[0082] The estimation unit 301, connection detection unit 302, and overlapping region determination unit 303 in the functional blocks of the communication control device 3 involved in this embodiment are the same as those in the first embodiment ( Figure 3 ) and / or the second embodiment ( Figure 5 Since they are the same, their description is omitted.

[0083] For a communication device 2F connected to one of the ground base stations 111, 121, or non-ground base station 131 within the overlapping area OA of ground communication cells 112 and 122 (first location registration area TA1) and non-ground communication cell 132 (second location registration area TA2), the connection approval determination unit 312 determines whether it can connect to another of the ground base stations 111, 121, or non-ground base station 131. The type of base station to which the communication device 2F in the overlapping area OA is connected is detected by the connection detection unit 302. For a communication device 2F detected by the connection detection unit 302 as being connected to ground base stations 111 and 121, the connection approval determination unit 312 determines whether it can connect to another base station, namely communication satellite 131. Conversely, for a communication device 2F detected by the connection detection unit 302 as being connected to communication satellite 131, the connection approval determination unit 312 determines whether it can connect to another base station, namely ground base station 111 and 121.

[0084] By pre-determining whether a connection to another base station is possible, the connection destination of the communication device 2F can be quickly switched to the other base station in the event of an unexpected situation that renders the first base station unreachable. Furthermore, to prevent the communication device 2F from attempting useless connections if the other base station also becomes unreachable, preferably, the connection availability determination unit 312 determines whether the communication device 2F can connect to the other base station at a fixed or variable frequency and updates the connection availability determination result.

[0085] When the connection availability determination unit 312 determines that the communication device 2F within the overlapping area OA can connect to another base station, the connection establishment information holding unit 313 holds the connection establishment information for establishing a connection between the communication device 2F and the other base station. When an unexpected situation occurs that causes one base station to become unreachable, the communication device 2F within the overlapping area OA can quickly establish a connection with the other base station using the connection establishment information held by the connection establishment information holding unit 313. The connection establishment information holding unit 313 can be implemented by the core network CN, a base station serving as a connection switching source, or another base station serving as a connection switching destination, but it is preferable that it be implemented by the communication device 2F itself, thereby enabling the communication device 2F to quickly and proactively switch connection destinations.

[0086] When the connection establishment information holding unit 313 is located outside the communication device 2F, the core network CN and / or a base station acting as a connection switching source notify the communication device 2F of the location of the connection establishment information holding unit 313 and the connection establishment information held there for establishing a connection with another base station. Upon receiving this notification, the communication device 2F can anticipate the possibility of switching the connection destination to another base station and, in the event of an unexpected situation, can quickly establish a connection with the other base station based on the connection establishment information at the notified location.

[0087] By providing a connection establishment information retention unit 313 at least outside the core network CN, time-consuming queries to the core network CN are eliminated for switching to the destination network, thus shortening network handover time compared to conventional methods. Furthermore, preferably, the connection establishment information retention unit 313 updates the connection establishment information each time the connection success determination unit 312 updates the connection success determination result. Alternatively, when the connection success determination result of the connection success determination unit 312 is updated to "unable to connect to another base station," the connection establishment information retention unit 313 may discard the retained connection establishment information or continue to retain it to handle situations where the connection success determination result of the connection success determination unit 312 is updated again to "able to connect to another base station."

[0088] When communication device 2F in the overlapping area OA becomes unable to connect to a base station it previously connected to (e.g., ground base stations 111 and 121), the connection control unit 305 connects the communication device 2F to another base station (e.g., communication satellite 131) that the connection establishment information held by the connection establishment information holding unit 313 is determined by the connection availability determination unit 312 to be able to connect.

[0089] Figure 7 This is a functional block diagram of the communication control device 3 according to the fourth embodiment. The communication control device 3 includes components similar to those in the first embodiment (…). Figure 3 ), second implementation method ( Figure 5 ) and / or the third embodiment ( Figure 6 Similar overlapping area determination unit 303 and connection control unit 305 are included, and a communication device management unit 314 is additionally included. Repeated descriptions of functional blocks common to the first embodiment, second embodiment, and / or third embodiment are omitted.

[0090] In this embodiment, the first location registration area TA1, which includes terrestrial communication cells 112 and 122, and the second location registration area TA2, which includes non-terrestrial communication cell 132, are assigned different TACs "#1", "#2", or the same TAC "#1". That is, the first location registration area TA1 and the second location registration area TA2 can be the same as those in the first embodiment ( Figure 3 Similarly, different location registration areas can be formed, which can also be used in the second embodiment ( Figure 5 Similarly, a large integrated location registration area is formed. This embodiment relates to any communication device 2 that can connect to at least one type of communication cell among terrestrial communication cells 112, 122 (first location registration area TA1, etc.) and non-terrestrial communication cell 132 (second location registration area TA2, etc.) regardless of the structure of the location registration area or the location of the communication device 2. Figure 7 The management of connection permissions and communication control for communication devices (such as 2E to 2I).

[0091] In existing technology, to manage the connection permissions of communication device 2 to wireless communication system 1, an EIR (Equipment Identity Register) is set up in the core network CN. The EIR is a database for communication device 2 (UE). Besides recording communication device-specific information such as the IMEI (International Mobile Equipment Identity) or communication device ID used to determine each communication device 2, it also records whether each communication device 2 has connection permissions to wireless communication system 1 (especially terrestrial communication systems such as 5G wireless communication system 11), or categorizes it as "White," "Black," or "Grey." For example, communication device 2 with connection permissions ("White") is allowed to connect to wireless communication system 1, while communication device 2 without connection permissions ("Black") is prohibited from connecting to wireless communication system 1. Additionally, communication device 2 with undetermined connection permissions ("Grey") is also registered in the EIR.

[0092] Since existing EIRs are designed for terrestrial communication systems such as 5G wireless communication system 11, malfunctions occur when applied to wireless communication systems 1 where terrestrial and satellite communication systems 13 coexist. For example, if a communication device 2F is classified as "White" in the EIR within the overlapping area OA of the first location registration area TA1 (part of the terrestrial communication system) and the second location registration area TA2 (part of the non-terrestrial communication system), it is unclear whether it has connection permissions to both the terrestrial and non-terrestrial communication systems or only one of them. Similarly, if a communication device 2F is classified as "Black" in the EIR within the overlapping area OA, it is unclear whether it lacks connection permissions to both the terrestrial and non-terrestrial communication systems or only one of them. The communication control device 3 according to this embodiment manages the connection permissions to the terrestrial and non-terrestrial communication systems respectively.

[0093] The communication equipment management department 314 includes any communication device 2 capable of communicating with at least one of the terrestrial system and the non-terrestrial system communication system. Figure 7The communication equipment 2E-2I, etc., is registered and managed in the EIR or the communication equipment inherent information retention unit within the core network CN. The communication equipment management unit 314 includes: a first connection permission management unit 315, which registers and manages the first connection permission (TN connection permission) of the communication equipment 2 to the ground base stations 111, 121 (terrestrial communication system / first location registration area TA1, etc.); and a second connection permission management unit 316, which registers and manages the second connection permission (NTN connection permission) of the communication equipment 2 to the non-terrestrial base station 131 (non-terrestrial communication system / second location registration area TA2, etc.).

[0094] Figure 8 The diagram schematically illustrates the process by which the communication equipment management unit 314 registers the communication equipment 2F with the EIR for management. Furthermore, although in Figure 7 The communication device 2F is located within the overlapping area OA of the first location registration area TA1 and the second location registration area TA2, but... Figure 8 The location of communication device 2F during EIR registration is arbitrary, and it is situated within... Figure 7 The communication device 2F can communicate with the Radio Access Network (RAN), including terrestrial base stations 111, 121 and non-terrestrial base station 131, within any terrestrial communication cell 112, 122 (illustrated or not shown) or non-terrestrial communication cell 132. The communication device 2F sends a registration request to the Access and Mobility Management Function (AMF) in the core network CN via the connected RAN.

[0095] Upon receiving a registration request from communication device 2F, the AMF or core network CN references at least one of the following: performance information, corresponding frequency information, contract information, location information, activity history information, and legal and regulatory information of the region or country (location) where communication device 2F is located. It then registers TN connection permissions for terrestrial communication systems and NTN connection permissions for non-terrestrial communication systems in the EIR. Here, the TN connection permission, as the first connection permission, is registered by the first connection permission management unit 315, and the NTN connection permission, as the second connection permission, is registered by the second connection permission management unit 316. Figure 8 In the example, the TN connection permission and NTN connection permission of communication device 2F are both registered as "White". As a result, communication device 2F can connect to both terrestrial systems and non-terrestrial systems.

[0096] Furthermore, consider the following scenario: even if the performance information, corresponding frequency information, contract information, and activity history information of communication device 2 indicate that communication device 2 has the capability to connect or communicate with, for example, satellite communication system 13, the connection or communication with satellite communication system 13 is not yet legalized due to legal restrictions in the region or country where communication device 2 is located. In this case, the second connection permission management unit 316, referring to the legal and regulatory information of the region or country where communication device 2 is located, registers NTN connection permissions (second connection permissions) such as "Black" indicating prohibition of communication device 2 from connecting to satellite communication system 13 and / or "Grey" indicating not recommended, into the EIR. Figure 8 In the examples shown, communication devices such as 2G, 2H, and 2I conform to this situation.

[0097] The connection control unit 305 restricts the connection of "Black" or "Grey" communication devices 2E and 2I, which do not have the first connection permission (TN connection permission) of "White", to ground base stations 111 and 121, and restricts the connection of "Black" or "Grey" communication devices 2G, 2H, and 2I, which do not have the second connection permission (NTN connection permission) of "White", to non-terrestrial base station 131. For example, although Figure 7 and Figure 8 In the examples, communication device 2E is located in the first location registration area TA1 (terrestrial communication cells 112, 122), but its connection to terrestrial base stations 111, 121 is prohibited because its TN connection permission is "Black". Communication device 2G, although located in the second location registration area TA2 (satellite communication cell 132), has its connection to communication satellite 131 restricted because its NTN connection permission is "Grey". Communication device 2H, although located in the overlapping area of ​​the second location registration area TA2 (satellite communication cell 132) and the third location registration area TA3 (terrestrial communication cells 112, 122), has its connection to communication satellite 131 prohibited because its NTN connection permission is "Black", and only its connection to terrestrial base stations 111, 121 is permitted. Communication device 2I, although located in the third location registration area TA3 (terrestrial communication cells 112, 122), has its connection to terrestrial base stations 111, 121 restricted because its TN connection permission is "Grey".

[0098] Since the TN connection permission and NTN connection permission of the communication device 2F in the overlapping area OA of the first location registration area TA1 (terrestrial communication cells 112, 122) and the second location registration area TA2 (satellite communication cell 132) are both "White", it can connect to both terrestrial base stations 111, 121 and the communication satellite 131. This communication device 2F in the overlapping area OA is detected by the overlapping area determination unit 303. Then, if the communication device 2F in the overlapping area OA has a "White" TN connection permission (first connection permission), regardless of whether it has NTN connection permission (second connection permission) or what its NTN connection permission is, the connection control unit 305 connects the communication device 2F to the terrestrial base stations 111, 121. By prioritizing the connection of the communication device 2F in the overlapping area OA to the terrestrial base stations 111, 121, the limited communication resources (including power) of the communication satellite 131 can be saved. Furthermore, as a variation, when both the TN and NTN connection permissions of communication device 2F are "White", the communication quality of TN and NTN can be compared to allow communication device 2F to connect to the one with better communication quality.

[0099] As described above, the connection control unit 305 initiates connection control of each communication device 2 by querying the EIR from the AMF in the core network CN, which receives connection requests from each communication device 2, regarding the TN connection permissions and / or NTN connection permissions of each communication device 2. This query from the AMF to the EIR... Figure 8 The value is displayed as "N5g-eir_MEIdentityCheck". Figure 8 In the example, based on the connection request from communication device 2F, the query from AMF to EIR shows that both TN and NTN connection permissions are "White".

[0100] As previously described, since the overlapping area determination unit 303 detects that the communication device 2F, located within the overlapping area OA, preferentially connects to the TN, the AMF can initially query the EIR only for the TN connection permission (first connection permission) of the communication device 2F. When the result of this query is that the TN connection permission is "White", the connection control unit 305 connects the communication device 2F to the ground base stations 111 and 121 without the AMF querying the EIR for the NTN connection permission (second connection permission). On the other hand, when the TN connection permission of the communication device 2F is "Grey" or "Black", the AMF queries the EIR for the NTN connection permission (second connection permission). If the result of this query confirms that the NTN connection permission is stronger than the TN connection permission (more specifically, when the TN connection permission is "Grey" and the NTN connection permission is "White", or when the TN connection permission is "Black" and the NTN connection permission is "Grey" or "White"), then the connection control unit 305 connects the communication device 2F to the communication satellite 131.

[0101] In addition, such as Figure 7 Similar to communication devices 2E, 2G, and 2I, for communication device 2 located in a location that can only connect to either the TN or NTN, the AMF can query the EIR only for connection permissions related to the network with which connection is possible. Specifically, for communication device 2E in terrestrial communication cells 112 and 122, only TN connection permissions are queried; for communication device 2G in satellite communication cell 132, only NTN connection permissions are queried; and for communication device 2I in terrestrial communication cells 112 and 122, only TN connection permissions are queried.

[0102] The present invention has been described above based on the embodiments. Those skilled in the art should understand that the embodiments are exemplary, and various modifications may exist in the combination of their structural elements and processing procedures, and such modifications are also within the scope of the present invention.

[0103] Furthermore, the functional structures of the devices described in the embodiments can be implemented using hardware resources, software resources, or a combination of both. Processors, ROMs, RAMs, and other LSIs can be used as hardware resources. Operating systems, application programs, and other programs can be used as software resources.

[0104] Industrial utilization potential

[0105] This invention relates to communication control technology in communication systems.

[0106] Explanation of reference numerals in the attached figures

[0107] 1 Wireless communication system, 2 Communication equipment, 3 Communication control device, 4 Database, 11 5G wireless communication system, 12 4G wireless communication system, 13 Satellite communication system, 11 5G base station, 11 5G cell, 12 4G base station, 12 4G cell, 13 1 Communication satellite, 13 2 Satellite communication cell, 13 3 Gateway, 301 Estimation unit, 302 Connection detection unit, 303 Overlapping area determination unit, 304 Connection change restriction unit, 305 Connection control unit, 306 Area change detection unit, 307 Area change notification unit, 308 Connection history information retention unit, 309 First paging control unit, 310 Second paging control unit, 311 Base station type recording unit, 312 Connection availability determination unit, 313 Connection establishment information retention unit, 314 Communication equipment management unit, 315 First connection permission management unit, 316 Second connection permission management unit, TA1 First location registration area, TA2 Second location registration area, TA3 Third location registration area.

Claims

1. A communication control device, comprising: A first paging control unit causes a first paging signal to be transmitted from a ground-based base station or a non-ground-based base station in flight for a communication device within a location registration area, the location registration area including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground. The second paging control unit, in the absence of a response from the communication device to the first paging signal, causes a second paging signal for the communication device to be transmitted from another base station, either the ground base station or the non-ground base station. The base station estimation unit estimates the base station to which the communication device is connected, and the first paging control unit causes the base station estimated by the base station estimation unit to send the first paging signal; as well as The overlapping area determination unit determines the overlapping area between the terrestrial communication cell and the non-terrestrial communication cell, and the base station estimation unit estimates at least the base stations to which the communication equipment is connected within the overlapping area.

2. The communication control device according to claim 1, The base station estimation unit estimates the base station to which the communication device is connected based on at least one of the following: the performance information of the communication device, the corresponding frequency information of the communication device, the subscription information of the communication device, the location information of the communication device, the communication status information of the communication device, the activity history information of the communication device, and the activity history information of one or more other communication devices in the location registration area.

3. The communication control device according to claim 1, further comprising: The base station type recording unit records the type of base station to which the communication device was connected before the migration occurred, when the communication device migrates from a communication state to a non-communication state. The first paging control unit causes a base station of the type recorded by the base station type recording unit to send the first paging signal.

4. The communication control device according to claim 1, The first paging control unit causes the first paging signal to be transmitted from the ground base station. In the absence of a response to the first paging signal from the communication device, the second paging control unit causes the second paging signal to be transmitted from the non-terrestrial base station.

5. The communication control device according to any one of claims 1 to 4, The non-terrestrial base station is a communication satellite flying in space.

6. A communication control method, comprising: The first paging control step causes a first paging signal to be sent from one of a ground base station located on the ground and a non-ground base station in flight, for a communication device within a location registration area, the location registration area including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground. The second paging control step, in the absence of a response from the communication device to the first paging signal, causes a second paging signal for the communication device to be sent from another base station, either the ground base station or the non-ground base station. The base station estimation step estimates the base station to which the communication device is connected, wherein the estimated base station is caused to send the first paging signal; as well as The overlapping area determination step involves determining the overlapping area between the terrestrial communication cell and the non-terrestrial communication cell, wherein at least the base stations to which the communication equipment is connected within the overlapping area are estimated.

7. A communication control program product storing instructions for causing a computer to perform the following steps: The first paging control step causes a first paging signal to be sent from one of a ground base station located on the ground and a non-ground base station in flight, for a communication device within a location registration area, the location registration area including at least one ground communication cell provided by the ground base station to the ground and at least one non-ground communication cell provided by the non-ground base station to the ground. The second paging control step, in the absence of a response from the communication device to the first paging signal, causes a second paging signal for the communication device to be sent from another base station, either the ground base station or the non-ground base station. The base station estimation step estimates the base station to which the communication device is connected, wherein the estimated base station is caused to send the first paging signal; as well as The overlapping area determination step involves determining the overlapping area between the terrestrial communication cell and the non-terrestrial communication cell, wherein at least the base stations to which the communication equipment is connected within the overlapping area are estimated.

Images