Spoofing detection device and spoofing detection method

Abstract

The purpose of the present invention is to provide a technology which enables appropriate determination of spoofing. An acquisition unit acquires GNSS signal data of a mobile body and luminance around the mobile body. A determination unit determines whether there is spoofing in the GNSS signal data on the basis of the GNSS signal data and the luminance. For example, the determination unit determines that there is spoofing in the GNSS signal data when: a change in luminance is equal to or greater than a prescribed threshold value; and the acquisition unit acquires the GNSS signal data over the change in luminance.

Description

Spoofing detection device and spoofing detection method

[0001] The present disclosure relates to a spoofing detection device and a spoofing detection method.

[0002] Spoofing is known, in which a positioning device is made to misidentify its actual location by falsifying a Global Navigation Satellite System (GNSS) signal transmitted by an artificial satellite. Patent Document 1 proposes a technique for determining that spoofing is suspected when the difference between a travel distance, which is the difference between the most recent positioning result obtained from the GNSS signal and a past positioning result, and a travel distance obtained from the speed of a speed sensor, is equal to or greater than a threshold value.

[0003] Japanese Patent Application Laid-Open No. 2020-134350

[0004] However, with conventional technology, there was a problem in that when spoofing occurs in an environment where GNSS signals cannot be received, such as inside a tunnel, and at a point before the vehicle enters that environment or after it has exited that environment, it is not possible to determine whether or not spoofing has occurred.

[0005] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a technology that can appropriately determine spoofing.

[0006] The spoofing detection device according to the present disclosure includes an acquisition unit that acquires GNSS signal data of a moving body and the luminance around the moving body, and a determination unit that determines whether the GNSS signal data is spoofed or not based on the GNSS signal data and the luminance.

[0007] According to the present disclosure, whether or not GNSS signal data is spoofed is determined based on the GNSS signal data of a moving object and the brightness around the moving object. With this configuration, it is possible to appropriately determine whether or not GNSS signal data is spoofed.

[0008] The objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

[0009] FIG. 1 is a block diagram showing the configuration of a spoofing detection device according to embodiment 1. FIG. 2 is a diagram for explaining the spoofing detection device according to embodiment 1. FIG. 3 is a flowchart showing the operation of the spoofing detection device according to embodiment 1. FIG. 4 is a block diagram showing the configuration of a spoofing detection device according to embodiment 2. FIG. 5 is a flowchart showing the operation of the spoofing detection device according to embodiment 2. FIG. 6 is a block diagram showing the configuration of a spoofing detection device according to embodiment 3. FIG. 7 is a diagram for explaining the spoofing detection device according to embodiment 3. FIG. 8 is a flowchart showing the operation of the spoofing detection device according to embodiment 3. FIG. 9 is a block diagram showing the configuration of a spoofing detection device according to embodiment 4. FIG. 10 is a diagram for explaining the spoofing detection device according to embodiment 4. FIG. 11 is a flowchart showing the operation of the spoofing detection device according to embodiment 4. FIG. 12 is a block diagram showing the hardware configuration of a spoofing detection device according to another modification. FIG. 13 is a block diagram showing the hardware configuration of a spoofing detection device according to another modification. FIG. 14 is a block diagram showing the configuration of a server according to another modification. FIG. 15 is a block diagram showing the configuration of a communication terminal according to another modification.

[0010] <First Embodiment> Fig. 1 is a block diagram showing the configuration of a spoofing detection device 1 according to the first embodiment. In the first embodiment, the spoofing detection device is described as being provided in a mobile object, but as will be described later, it may also be provided in a server or the like. The mobile object may be, for example, a vehicle such as an automobile, or a drone. The following mainly describes an example in which the mobile object is a vehicle.

[0011] 1 includes an acquisition unit 11, a determination unit 12, and an output unit 13. The acquisition unit 11 includes a GNSS signal acquisition unit 11a and a sensor information acquisition unit 11b. The determination unit 12 includes a reception environment determination unit 12a.

[0012] The GNSS signal acquisition unit 11a acquires GNSS signal data from which the vehicle position can be calculated. For ease of explanation, hereinafter, the position information obtained from the GNSS signal data will be referred to simply as "GNSS signal data." The GNSS signal acquisition unit 11a may be a GNSS signal receiver or an interface for the GNSS signal receiver.

[0013] The sensor information acquiring unit 11b acquires sensor information generated by a sensor provided in the vehicle, and in the present embodiment, the sensor information includes the luminance around the vehicle. The sensor information acquiring unit 11b may be a sensor including an optical sensor or a camera, or may be a sensor interface.

[0014] The reception environment determination unit 12a determines whether or not the GNSS signal data is spoofed, based on the GNSS signal data acquired by the GNSS signal acquisition unit 11a and the luminance included in the sensor information acquired by the sensor information acquisition unit 11b. In the first embodiment, the reception environment determination unit 12a determines that the GNSS signal data is spoofed when the change in luminance is equal to or greater than a predetermined threshold and the GNSS signal acquisition unit 11a acquires GNSS signal data throughout the change in luminance.

[0015] 2 is a diagram illustrating the reception environment determination unit 12a. FIG. 2 shows GNSS signal data and luminance at times 1, 2, and 3. In the following description, it is assumed that the time of the GNSS signal data and the time of the luminance are synchronized by appropriate interpolation or the like. In the example of FIG. 2, it is assumed that the threshold value used to compare the change in luminance is 50.

[0016] In Figure 2, the change in brightness (=60 = |20-80|) over the period from time 2 to time 3 is greater than the threshold value (=50). Such a large change in brightness around the vehicle can occur when the vehicle enters a tunnel or under an overpass where GNSS signal data cannot be acquired. Despite this, in Figure 2, the GNSS signal acquisition unit 11a acquires (6,6,4) and (7,7,4) as GNSS signal data over the period in which the brightness changes, that is, over the period from time 2 to time 3.

[0017] In such a case, the reception environment determination unit 12 a determines that spoofing of the GNSS signal data has occurred. As a result, the reception environment determination unit 12 a can determine whether or not spoofing of the GNSS signal data has occurred even if spoofing has occurred both at a point in the environment where GNSS signals cannot be received and at a point before the vehicle enters the environment.

[0018] Note that, in the example of FIG. 2 , a case has been described in which the luminance has decreased by more than a threshold value and the GNSS signal acquisition unit 11a has acquired GNSS signal data throughout the decrease in luminance, but this is not limited to this. For example, the reception environment determination unit 12a may also determine that GNSS signal data spoofing has occurred when the luminance has increased by more than a threshold value and the GNSS signal acquisition unit 11a has acquired GNSS signal data throughout the increase in luminance. With this configuration, it is possible to determine whether GNSS signal data spoofing has occurred even when spoofing has occurred both at a point in an environment where GNSS signals cannot be received and at a point after the vehicle has left that environment. Furthermore, conventional technology has been unable to determine whether spoofing is more likely at the most recent time point where spoofing is suspected or at an earlier time point where spoofing is suspected. In contrast, with the above configuration, it is possible to determine whether spoofing is more likely at the most recent time point where spoofing is suspected or at an earlier time point where spoofing is suspected.

[0019] The storage unit that stores the past luminance and the presence or absence of past GNSS signal data may be provided within the reception environment determination unit 12a, or may be provided outside the reception environment determination unit 12a and within the spoofing detection device 1. The threshold value that is compared with the change in luminance may be changed as appropriate based on the most recent luminance.

[0020] 1 normally outputs the GNSS signal data acquired by the GNSS signal acquisition unit 11a to the outside of the spoofing detection device 1. However, if the output unit 13 determines that spoofing has occurred, the output unit 13 stops outputting the GNSS signal data determined to be spoofed. In this case, the output unit 13 may output information indicating that spoofing has occurred to the outside. The GNSS signal data output from the output unit 13 is used, for example, to calculate the distance traveled by the vehicle.

[0021] <Operation> FIG. 3 is a flowchart showing the determination operation of the spoofing detection device 1 according to the first embodiment.

[0022] In step S1, the sensor information acquisition unit 11b acquires sensor information including luminance.

[0023] In step S2, the reception environment determination unit 12a determines whether the change in luminance included in the sensor information is equal to or greater than a threshold value. If it is determined that the change in luminance is equal to or greater than the threshold value, the process proceeds to step S3. If it is determined that the change in luminance is not equal to or greater than the threshold value, the operation of FIG. 3 ends.

[0024] In step S3, the reception environment determination unit 12a determines whether the GNSS signal acquisition unit 11a is acquiring GNSS signal data throughout the change in luminance. If it is determined that the GNSS signal acquisition unit 11a is acquiring GNSS signal data, the process proceeds to step S4. If it is determined that the GNSS signal acquisition unit 11a is not acquiring GNSS signal data, the process proceeds to step S5.

[0025] In step S4, the reception environment determination unit 12a determines that the GNSS signal data is spoofed. As a result, the output unit 13 stops outputting the GNSS signal data. Then, the operation in FIG. 3 ends.

[0026] In step S5, the reception environment determination unit 12a determines that there is no spoofing of the GNSS signal data, and then the operation of FIG.

[0027] Summary of First Embodiment As described above, the spoofing detection device 1 according to the first embodiment determines whether or not the GNSS signal data is spoofed based on the GNSS signal data of the vehicle and the luminance around the vehicle. In the first embodiment, if the change in luminance is equal to or greater than a predetermined threshold and the GNSS signal acquirer 11 a acquires GNSS signal data across the change in luminance, it is determined that the GNSS signal data is spoofed.

[0028] With this configuration, it is possible to determine whether spoofing is occurring even if spoofing occurs at a location in an environment where GNSS signals cannot be received, such as inside a tunnel or under an overpass, or at a location before the vehicle enters or after it has left that environment. Furthermore, according to the first embodiment, it is possible to determine to some extent whether spoofing is occurring at a location in an environment where GNSS signals cannot be received, or at a location before the vehicle enters or after it has left that environment. Furthermore, according to the first embodiment, it is possible to determine whether spoofing is more likely at the most recent time point where spoofing is suspected, or at an earlier time point where spoofing is suspected.

[0029] However, when the vehicle speed is low, the vehicle position generally cannot be calculated correctly using a speed sensor, and therefore, it may not be possible to correctly determine whether or not spoofing is occurring based on the GNSS signal data and the speed obtained from the speed sensor. In contrast, in the first embodiment, the presence or absence of spoofing is determined without using a speed sensor, thereby avoiding such problems.

[0030] Furthermore, since the first embodiment does not use map information, a storage area for storing map information is not required. Furthermore, the first embodiment can determine whether or not spoofing has occurred based on whether or not GNSS signal data has been acquired over a range of brightness changes, without requiring arithmetic processing of the GNSS signal data, thereby enabling early determination of whether or not spoofing has occurred. Furthermore, the first embodiment can determine whether or not spoofing has occurred without requiring any communication other than communication for acquiring GNSS signal data.

[0031] <Variation of First Embodiment> For example, if the current time is around noon and the luminance is equal to or less than a predetermined threshold, it is considered that the vehicle is located in a tunnel or under an overpass. Therefore, the reception environment determination unit 12a may determine that GNSS signal data spoofing has occurred using the luminance at one time, rather than the change in luminance between two times. Specifically, the reception environment determination unit 12a may determine that the luminance is equal to or less than a predetermined threshold, and may determine that GNSS signal data spoofing has occurred if the GNSS signal acquisition unit 11a continues to acquire GNSS signal data around the time of this determination. Even with this configuration, it is possible to determine to some extent whether spoofing has occurred.

[0032] 4 is a block diagram showing the configuration of a spoofing detection device 1 according to a second embodiment. In the following, among the components according to the second embodiment, components that are the same as or similar to the components described above are given the same or similar reference numerals, and different components will be mainly described.

[0033] The configuration of FIG. 4 is the same as the configuration of FIG. 1 except that a map information storage unit 14 is added to the configuration of FIG. 1 and a travel route determination unit 12b is added to the determination unit 12.

[0034] The map information storage unit 14 stores map information, which includes information indicating the shape of the route and the terrain, and information indicating the type of the route and the terrain.

[0035] The travel route determination unit 12b determines whether the GNSS signal data is spoofed or not, based on the vehicle position determined based on the GNSS signal data acquired by the GNSS signal acquisition unit 11a and the map information in the map information storage unit 14. In the second embodiment, when the type of terrain or route in the portion of the map information that corresponds to the vehicle position determined based on the GNSS signal data is an ocean or the like where the vehicle cannot travel, the travel route determination unit 12b determines that spoofing is present.

[0036] In the second embodiment, the travel route determination unit 12b determines that spoofing has occurred when the type of terrain or route for the portion corresponding to the vehicle's position cannot be changed due to the vehicle's travel. For example, suppose that the type of the route for the portion corresponding to the vehicle's position determined based on the GNSS signal data is a general road, and then the type of the route for the portion corresponding to the vehicle's position determined based on the next GNSS signal data is a highway on which the vehicle cannot travel directly from the general road. If such a change in type occurs, the travel route determination unit 12b determines that GNSS signal data spoofing has occurred. Note that the storage unit for storing the past routes and types of terrain may be provided within the travel route determination unit 12b, or may be provided outside the travel route determination unit 12b and within the spoofing detection device 1.

[0037] <Operation> Fig. 5 is a flowchart showing the determination operation of the spoofing detection device 1 according to embodiment 2. The operation in Fig. 5 is the same as the operation in Fig. 3 with steps S11 and S12 added, so steps S11 and S12 will be mainly described below.

[0038] If it is determined in step S2 that the change in brightness is equal to or greater than the threshold value, the process proceeds to step S3, and if it is not determined that the change in brightness is equal to or greater than the threshold value, the process proceeds to step S11.

[0039] In step S11, the GNSS signal acquisition unit 11a acquires GNSS signal data.

[0040] In step S12, the travel route determination unit 12b determines whether the GNSS signal data is spoofed based on the vehicle position calculated based on the GNSS signal data and the map information. If it is determined that the GNSS signal data is spoofed, the process proceeds to step S4, and if it is determined that the GNSS signal data is not spoofed, the operation in FIG. 5 ends.

[0041] Summary of Second Embodiment As described above, the spoofing detection device 1 according to the second embodiment determines whether or not the GNSS signal data is spoofed based on the vehicle position calculated based on the GNSS signal data and on map information. This configuration can improve the accuracy of determining whether the GNSS signal data is spoofed.

[0042] <Variation of embodiment 2> For example, if the moving body is a drone and the type of terrain in the part of the map information corresponding to the drone's position is an airport where drones cannot move, the movement path determination unit 12b may determine that GNSS signal data has been spoofed.

[0043] 6 is a block diagram showing the configuration of a spoofing detection device 1 according to a third embodiment. In the following, among the components according to the third embodiment, components that are the same as or similar to the components described above are given the same or similar reference numerals, and different components will be mainly described.

[0044] The configuration of FIG. 6 is the same as the configuration of FIG. 4, except that a movement distance determination unit 12c is added to the determination unit 12.

[0045] The sensor information acquisition unit 11b in FIG. 6 acquires sensor information in the same manner as in the first embodiment. However, in the third embodiment, the sensor information includes not only luminance but also vehicle travel information. The travel information may be information different from GNSS signal data that can acquire a travel distance, which is the distance traveled by the vehicle. For example, the sensor information may be the travel distance of the vehicle itself, or the position, speed, or acceleration of the vehicle from which the travel distance of the vehicle can be calculated.

[0046] The travel distance determiner 12c determines whether the GNSS signal data is spoofed based on the difference between the vehicle travel distance calculated based on the GNSS signal data and the vehicle travel distance calculated based on the travel information included in the sensor information. In the third embodiment, the travel distance determiner 12c calculates the vehicle's position at different times based on the GNSS signal data at different times, and calculates the difference between the vehicle's positions at the different times as the vehicle's travel distance. If the difference between the vehicle's travel distance calculated in this way and the vehicle's travel distance calculated based on the travel information is equal to or greater than a predetermined threshold, the travel distance determiner 12c determines that the GNSS signal data is spoofed.

[0047] Fig. 7 is a diagram illustrating the travel distance determination unit 12c. Fig. 7 shows the vehicle position calculated based on the GNSS signal data at times 1, 2, and 3, and the speed, which is an example of travel information. In the example of Fig. 7, the predetermined threshold value to be compared with the difference in travel distance is set to 4.

[0048] 7, the x, y, and z components of the change in vehicle position calculated based on the GNSS signal data during the transition from time 1 to time 2 are 1 (=|6-5|), 1 (=|6-5|), and 0 (=|4-4|). In other words, the x, y, and z components of the traveled distance calculated based on the GNSS signal data during the transition from time 1 to time 2 are (1, 1, 0).

[0049] On the other hand, the x, y, and z components of the travel distance corresponding to the speed at time 1 are (7, 7, 0), and the x, y, and z components of the travel distance corresponding to the speed at time 2 are (8, 8, 0). Therefore, the difference (= 6.5 × √2) between the travel distance calculated based on the GNSS signal data (= √2) and the average value of the travel distance corresponding to the speed (= 7.5 × √2) is greater than the threshold value (= 4).

[0050] In such a case, the travel distance determination unit 12c determines that the GNSS signal data is spoofed. Note that the storage unit that stores the past vehicle positions may be provided within the travel distance determination unit 12c, or may be provided outside the travel distance determination unit 12c and within the spoofing detection device 1.

[0051] <Operation> Fig. 8 is a flowchart showing the determination operation of the spoofing detection device 1 according to embodiment 3. The operation in Fig. 8 is the same as the operation in Fig. 5 with step S16 added, so the following description will mainly focus on step S16.

[0052] In step S1, the sensor information acquisition unit 11b acquires sensor information including brightness and driving information.

[0053] If it is determined in step S12 that the GNSS signal data is spoofed, the process proceeds to step S4, and if it is determined that the GNSS signal data is not spoofed, the process proceeds to step S16.

[0054] In step S16, the travel distance determination unit 12c determines whether the GNSS signal data is spoofed based on the difference between the travel distance of the vehicle calculated based on the GNSS signal data and the travel distance of the vehicle calculated based on the travel information. If it is determined that the GNSS signal data is spoofed, the process proceeds to step S4, and if it is determined that the GNSS signal data is not spoofed, the operation in FIG. 8 ends.

[0055] Summary of Third Embodiment As described above, the spoofing detection device 1 according to the third embodiment determines whether or not GNSS signal data is spoofed based on the difference between the vehicle travel distance calculated based on the GNSS signal data and the vehicle travel distance calculated based on the travel information. This configuration can improve the accuracy of spoofing determination.

[0056] 9 is a block diagram showing the configuration of a spoofing detection device 1 according to a fourth embodiment. In the following, among the components according to the fourth embodiment, components that are the same as or similar to the components described above are given the same or similar reference numerals, and different components will be mainly described.

[0057] The configuration of FIG. 9 is the same as the configuration of FIG. 6 in which a communication signal acquisition unit 11c is added to the acquisition unit 11 and a communication signal determination unit 12d is added to the determination unit 12.

[0058] The communication signal acquisition unit 11c acquires a communication signal indicating vehicle position information through wireless communication between the vehicle and an external device located away from the vehicle. The external device is, for example, a ground base station such as a Real Time Kinematic (RTK) base station used as an auxiliary means for positioning. For the wireless communication, for example, Dedicated Short Range Communications (DSRC), 4G, 5G, or Indoor Messaging System (IMES) communication is used. The communication signal acquisition unit 11c may be a wireless communication device or an interface for a wireless communication device.

[0059] The communication signal determination unit 12d determines whether the GNSS signal data is spoofed based on the GNSS signal data, the travel information included in the sensor information, and the position information indicated by the communication signal. In the fourth embodiment, the communication signal determination unit 12d determines, as the vehicle travel distance, the difference between the vehicle position determined based on the GNSS signal data at a certain time and the vehicle position indicated by the position information at a time different from the certain time. Then, when the difference between the vehicle travel distance determined in this way and the vehicle travel distance determined based on the travel information is equal to or greater than a predetermined threshold, the communication signal determination unit 12d determines that the GNSS signal data is spoofed.

[0060] 10 is a diagram illustrating the communication signal determination unit 12d. Fig. 10 shows the vehicle positions calculated based on the GNSS signal data at times 1, 2, and 3, the vehicle positions indicated by the position information of the communication signals, and the speed, which is an example of the travel information. In the example of Fig. 10, the predetermined threshold value compared with the difference in travel distance is set to 4.

[0061] 10, the x, y, and z components of the vehicle position indicated by the position information of the communication signal at time 1 are (5, 5, 3), and the x, y, and z components of the vehicle position calculated based on the GNSS signal data at time 2 are (6, 6, 4). Therefore, the x, y, and z components of the travel distance during the transition from time 1 to time 2 are (1, 1, 1).

[0062] On the other hand, the x, y, and z components of the travel distance corresponding to the speed at time 1 are (7, 7, 0), and the x, y, and z components of the travel distance corresponding to the speed at time 2 are (8, 8, 0). Therefore, the difference (= 7.5 × √2 - √3 ≈ 8.8) between the travel distance calculated based on the GNSS signal data and the communication signal (= √3) and the average value of the travel distance corresponding to the speed (= 7.5 × √2) is greater than the threshold value (= 4).

[0063] In such a case, the communication signal determination unit 12d determines that the GNSS signal data is spoofed. Note that the storage unit that stores the past vehicle positions determined based on the past GNSS signal data and the past communication signals may be provided within the communication signal determination unit 12d, or may be provided outside the communication signal determination unit 12d and within the spoofing detection device 1. Also, the above determination is an example, and the determination is not limited to the above as long as the communication signal determination unit 12d determines whether the GNSS signal data is spoofed based on the GNSS signal data, the traveling information, and the position information.

[0064] <Operation> Fig. 11 is a flowchart showing the determination operation of the spoofing detection device 1 according to embodiment 4. The operation in Fig. 11 is the same as the operation in Fig. 8 with steps S21 and S22 added, so steps S21 and S22 will be mainly described below.

[0065] If it is determined in step S16 that GNSS signal data is spoofed, the process proceeds to step S4, and if it is determined that GNSS signal data is not spoofed, the process proceeds to step S21.

[0066] In step S21, the communication signal acquisition unit 11c acquires a communication signal indicating vehicle position information through wireless communication with an external device.

[0067] In step S22, the communication signal determination unit 12d determines whether or not the GNSS signal data is spoofed based on the GNSS signal data, the driving information, and the position information of the communication signal. If it is determined that the GNSS signal data is spoofed, the process proceeds to step S4, and if it is determined that the GNSS signal data is not spoofed, the operation in FIG. 11 ends.

[0068] Summary of Fourth Embodiment As described above, the spoofing detection device 1 according to the fourth embodiment determines whether or not the GNSS signal data is spoofed based on the GNSS signal data, the driving information, and the position information obtained by wireless communication. With this configuration, it is possible to improve the accuracy of determining whether the GNSS signal data is spoofed.

[0069] <Modifications of Embodiments 1 to 4> The configuration of Embodiment 1 may be combined with at least one of the configurations of Embodiments 2 to 4. For example, in Embodiment 2, the travel route determination unit 12b may determine a position obtained by moving a travel distance calculated based on travel information included in the sensor information from the vehicle position calculated based on the GNSS signal. Then, the travel route determination unit 12b may determine that spoofing has occurred when the type of terrain or route in the portion of the map information corresponding to the position is, for example, ocean, where the vehicle cannot travel.

[0070] <Other Modifications> The acquisition unit 11 and determination unit 12 in FIG. 1 described above will hereinafter be referred to as the "acquisition unit 11, etc." The acquisition unit 11, etc. are realized by a processing circuit 81 shown in FIG. 12. That is, the processing circuit 81 includes the acquisition unit 11 that acquires GNSS signal data of a moving object and luminance around the moving object, and the determination unit 12 that determines whether the GNSS signal data is spoofed based on the GNSS signal data and the luminance. The processing circuit 81 may be implemented by dedicated hardware, or may be implemented by a processor that executes a program stored in memory. Examples of the processor include a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, and a DSP (Digital Signal Processor).

[0071] When the processing circuitry 81 is dedicated hardware, the processing circuitry 81 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The functions of each unit, such as the acquisition unit 11, may be realized by a circuit in which processing circuits are distributed, or the functions of each unit may be realized together by a single processing circuit.

[0072] When the processing circuit 81 is a processor, the functions of the acquisition unit 11 and the like are realized in combination with software and the like. Software and the like may include, for example, software, firmware, or software and firmware. The software and the like is written as a program and stored in memory. As shown in FIG. 13 , the processor 82 applied to the processing circuit 81 realizes the functions of each unit by reading and executing a program stored in the memory 83. That is, the spoofing detection device 1 includes a memory 83 for storing a program that, when executed by the processing circuit 81, results in the steps of acquiring GNSS signal data of a moving object and luminance around the moving object, and determining whether the GNSS signal data is spoofed based on the GNSS signal data and luminance. In other words, this program can be said to cause a computer to execute the procedures and methods of the acquisition unit 11 and the like. Here, the memory 83 may be, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), or an EEPROM (Electrically Erasable Programmable Read Only Memory), a HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disc), a drive device for any of these, or any storage medium to be used in the future.

[0073] The above describes a configuration in which each function of the acquisition unit 11 and the like is realized either by hardware or software, etc. However, this is not limited to this, and a configuration in which part of the acquisition unit 11 and the like is realized by dedicated hardware and another part is realized by software, etc. For example, the function of the acquisition unit 11 can be realized by a processing circuit 81 as dedicated hardware, and the other functions can be realized by the processing circuit 81 as a processor 82 reading and executing a program stored in a memory 83.

[0074] As described above, the processing circuitry 81 can realize the above-described functions by hardware, software, or a combination of these.

[0075] The spoofing detection device described above can also be applied to a spoofing detection system constructed as a system by appropriately combining a vehicle device, a communication terminal, the functions of an application installed on at least one of the vehicle device and the communication terminal, and a server. Communication terminals include, for example, mobile phones, smartphones, and tablets. The functions or components of the spoofing detection device described above may be distributed among the devices that constitute the system, or may be centrally located in one of the devices.

[0076] Fig. 14 is a block diagram showing the configuration of a server 91 according to this modification. The server 91 in Fig. 14 includes a communication unit 91a and a control unit 91b, and is capable of wireless communication with a vehicle device 93 of a vehicle 92.

[0077] The communication unit 91 a, which is an acquisition unit, receives GNSS signal data acquired by the vehicle device 93 and the brightness around the vehicle 92 by wirelessly communicating with the vehicle device 93 .

[0078] The control unit 91b has the same function as the determination unit 12 in FIG. 1 by causing a processor (not shown) of the server 91 to execute a program stored in a memory (not shown) of the server 91. In other words, the control unit 91b determines whether the GNSS signal data is spoofed or not based on the GNSS signal data and the luminance. The communication unit 91a then transmits the determination result of the control unit 91b to the vehicle device 93. The server 91 configured in this manner can achieve the same effects as the spoofing detection device 1 described in the first embodiment.

[0079] Fig. 15 is a block diagram showing the configuration of a communication terminal 96 according to this modification. The communication terminal 96 in Fig. 15 includes a communication unit 96a similar to the communication unit 91a and a control unit 96b similar to the control unit 91b, and is capable of wireless communication with a vehicle device 98 of a vehicle 97. Note that the communication terminal 96 may be, for example, a mobile terminal such as a mobile phone, smartphone, or tablet carried by the driver of the vehicle 97. The communication terminal 96 configured in this manner can achieve the same effects as the spoofing detection device 1 described in the first embodiment.

[0080] It should be noted that the embodiments and modifications may be freely combined, and the embodiments and modifications may be modified or omitted as appropriate.

[0081] The above description is illustrative in all respects and is not restrictive. It is understood that countless variations not illustrated can be envisioned.

[0082] 1 spoofing detection device, 11 acquisition unit, 12 determination unit

Claims

1. An acquisition unit that acquires GNSS signal data of a moving body and the luminance around the moving body; A determination unit that determines the presence or absence of spoofing of the GNSS signal data based on the GNSS signal data and the luminance; Comprising: The determination unit determines that there is spoofing of the GNSS signal data when the change in the luminance is equal to or greater than a predetermined threshold value and the acquisition unit acquires the GNSS signal data over the change in the luminance. A spoofing detection device.

2. The spoofing detection device according to claim 1, wherein The determination unit determines the presence or absence of spoofing of the GNSS signal data based on the position of the moving body obtained based on the GNSS signal data and map information. A spoofing detection device.

3. The spoofing detection device according to claim 1 or claim 2, wherein The acquisition unit further acquires traveling information of the moving body, which is different from the GNSS signal data, The determination unit determines the presence or absence of spoofing of the GNSS signal data based on the difference between the moving distance of the moving body obtained based on the GNSS signal data and the moving distance of the moving body obtained based on the traveling information. A spoofing detection device.

4. The spoofing detection device according to claim 1, wherein The acquisition unit further acquires traveling information of the moving body, which is different from the GNSS signal data, and position information of the moving body by wireless communication with an external device separated from the moving body, The determination unit determines the presence or absence of spoofing of the GNSS signal data based on the GNSS signal data, the traveling information, and the position information. A spoofing detection device.

5. An acquisition unit acquires GNSS signal data of a moving body and the luminance around the moving body, A determination unit determines the presence or absence of spoofing of the GNSS signal data based on the GNSS signal data and the luminance, The determination unit determines that there is spoofing of the GNSS signal data when the change in the luminance is equal to or greater than a predetermined threshold value and the acquisition unit acquires the GNSS signal data over the change in the luminance. A spoofing detection method.