WO2021166222A1

WO2021166222A1 - Positioning device and positioning method

Info

Publication number: WO2021166222A1
Application number: PCT/JP2020/007069
Authority: WO
Inventors: 美穂久宮; 天平近藤; 遼平原田; 大樹松本
Original assignee: 日本電気株式会社; 日本電気航空宇宙システム株式会社
Priority date: 2020-02-21
Filing date: 2020-02-21
Publication date: 2021-08-26
Also published as: JP7372436B2; JPWO2021166222A1

Abstract

[Problem] To provide technology for assessing the normality of a positioning signal transmitted by a positioning satellite. [Solution] This positioning device comprises a position calculation unit for calculating a first position indicating the position of a positioning satellite that transmitted a radio wave including a positioning signal, the position being based on the direction from which the radio wave has arrived, and calculating a second position indicating the position of the positioning satellite based on orbit information for the positioning satellite that is included in the positioning signal, and a determination unit for determining the normality of the received positioning signal on the basis of the result of comparing the first position and the second position.

Description

Positioning device and positioning method

The present invention relates to a positioning device and a positioning method, and more particularly to a positioning device and a positioning method in a positioning system using a positioning satellite.

The position information system (GNSS) using satellites is widely used for positioning mobile objects such as aircraft. GNSS includes, for example, GPS developed in the United States and GLONASS developed in Russia. GNSS is an abbreviation for Global Navigation Satellite System, GPS is an abbreviation for Global Positioning System, and GLONASS is an abbreviation for Global Navigation Satellite System. The aircraft receives the positioning signal transmitted by the GNSS satellite and knows the position of the aircraft. By receiving positioning signals from multiple GNSS satellites, the aircraft can position itself with less error.

On the other hand, there is SBAS (wide area reinforcement system) as one of the systems that reduce the positioning error caused by the error of the positioning signal received by the aircraft. SBAS is an abbreviation for Satellite Based Augmentation System. The ground control station receives the positioning signal from the GNSS satellite and transmits the augmentation information including the integrity information (integrity) of the GNSS and the error correction information of the positioning signal to the SBAS satellite. The SBAS satellite is, for example, a geostationary satellite, and the SBAS satellite transmits augmentation information provided by the control station as a positioning signal to the aircraft. The aircraft receives the positioning signals transmitted by the GNSS satellite and the SBAS satellite, and corrects the positioning by the GNSS satellite using the augmentation information contained in the positioning signals received from the SBAS satellite. By receiving positioning signals from both the GNSS satellite and the SBAS satellite, the aircraft can perform highly accurate positioning of its own aircraft.

In relation to the present invention, Patent Document 1 describes a technique for detecting an abnormality in a satellite signal due to an interfering wave. Patent Document 2 describes an outline of the SBAS system.

Japanese Unexamined Patent Publication No. 2001-280997 Japanese Unexamined Patent Publication No. 2011-237205

The specifications of the positioning signals transmitted by the GNSS satellite and the SBAS satellite are open to the public. Also, these signals are not encrypted. Therefore, spoofing of the positioning signal becomes possible by transmitting a signal having the same specifications as the positioning signal transmitted by the GNSS satellite or the SBAS satellite to the mobile body. Such spoofing causes an abnormal positioning result to be generated in the moving body that receives the signal. Therefore, it is preferable that the mobile body that performs positioning by the GNSS satellite or the SBAS satellite can determine whether or not the received positioning signal is a spoofing signal.
(Purpose of Invention)
An object of the present invention is to provide a technique for determining the normality of a positioning signal transmitted by a positioning satellite.

The positioning device of the present invention calculates a first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal, and also uses the orbit information of the positioning satellite included in the positioning signal. A position calculation means for calculating a second position indicating the position of the positioning satellite based on the above,
A determination means for determining the normality of the received positioning signal based on the comparison result between the first position and the second position, and
To be equipped.

The positioning method of the present invention calculates a first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal is calculated.
Based on the comparison result between the first position and the second position, the normality of the received positioning signal is determined.
Including that.

The recording medium of the positioning program of the present invention is
To the computer of the positioning device
A procedure for calculating a first position indicating the position of a positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A procedure for calculating a second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal.
A procedure for determining the normality of the received positioning signal based on the comparison result between the first position and the second position.
Record the positioning program to execute.

The present invention can determine the normality of the positioning signal transmitted by the positioning satellite.

It is a figure which shows the configuration example of the positioning system 10 of 1st Embodiment. It is a block diagram which shows the structural example of the positioning apparatus 100 of 1st Embodiment. It is a flowchart which shows the operation example of the positioning apparatus 100. It is a block diagram which shows the structural example of the positioning apparatus 101 of 2nd Embodiment. It is a figure which shows the example of the 1st position. It is a figure which shows the 1st example of the search result of a 2nd position. It is a figure which shows the 2nd example of the search result of the 2nd position. It is a flowchart which shows the operation example of the positioning apparatus 101. It is a block diagram which shows the structural example of the positioning apparatus 102 of 3rd Embodiment. It is a block diagram which shows the structural example of the positioning apparatus 103 of 4th Embodiment. It is a block diagram which shows the structural example of the positioning apparatus 104 of 5th Embodiment. It is a block diagram which shows the structural example of the positioning apparatus 105 of 6th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each embodiment, the existing components are given the same name and reference numeral, and the description of the duplicated function is omitted. Each embodiment can be applied to any of a positioning system in which a GNSS satellite is used as a positioning satellite and a positioning system in which an SBAS satellite is used in combination. Hereinafter, the GNSS satellite and the SBAS satellite are collectively referred to as a positioning satellite, and the signals transmitted from the GNSS satellite and the SBAS satellite and including data used for positioning are collectively referred to as a positioning signal.

In the block diagram of the positioning device of each embodiment, each block is composed of an electric circuit. Between those blocks, functional data is transmitted and received as electrical signals.

(First Embodiment)
FIG. 1 is a diagram showing a configuration example of the positioning system 10 according to the first embodiment of the present invention. The positioning system 10 is a satellite positioning system including a mobile body 200 and a positioning satellite 300. The positioning satellite is a GNSS satellite, for example, a GPS satellite. The positioning satellite 300 may include an SBAS satellite. The mobile body 200 receives radio waves including a positioning signal from the positioning satellite 300 and positions itself. The mobile body 200 includes a positioning device 100. The positioning signal transmitted by the SBAS satellite includes augmentation information for improving the accuracy of positioning by the GNSS satellite. The positioning device 100 will be described below.

FIG. 2 is a block diagram showing a configuration example of the positioning device 100 according to the first embodiment of the present invention. The positioning device 100 includes a position calculation unit 110 and a determination unit 120. When a radio wave including a positioning signal is received from the positioning satellite 300, the position calculation unit 110 calculates a first position indicating the position of the positioning satellite 300 based on the arrival direction of the radio wave at that time. The first position is represented, for example, as a position on the sky map of the positioning satellite 300. The sky map is a commonly used diagram showing the arrangement of positioning satellites when the sky is viewed from a radio wave receiving point, for example, with the horizontal axis in the east-west direction and the vertical axis in the north-south direction. The embodiment using the sky map will be described in the second embodiment.

The position calculation unit 110 further calculates a second position indicating the position of the positioning satellite 300 based on the orbit information included in the positioning signal. The positioning signal is included in the radio wave transmitted by the positioning satellite 300. The positioning signal includes the orbit information of the positioning satellite 300 that transmits the positioning signal and the orbit information of other positioning satellites. For example, the almanac included in the positioning signal includes orbit information of GPS satellites other than the GPS satellite that transmits the positioning signal. The positioning signal transmitted by the SBAS satellite also includes the orbit information of the SBAS satellite other than the SBAS satellite that transmits the positioning signal. The orbit information is strictly managed in the positioning system and provides highly reliable orbit information for each positioning satellite. The procedure for calculating the coordinates indicating the position of each positioning satellite at an arbitrary time from the orbit information is known. Therefore, from the positioning signal, at least the position (second position) obtained from the orbit information of the positioning satellite that transmitted the positioning signal can be calculated. Further, when the positioning signal includes Armanac, the positions of other positioning satellites can be calculated.

In this way, the position calculation unit 110 calculates the second position indicating the position of the positioning satellite 300 based on the orbit information. The second position can be expressed as, for example, the arrangement of the positioning satellite 300 on the sky map obtained from the orbit information. The position calculation unit 110 having the above-mentioned function is an example of the position calculation means.

The determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position and the second position. The first position and the second position are input to the determination unit 120. The determination unit 120 compares the first position and the second position for each positioning satellite 300. Then, when the first position and the second position substantially match, the determination unit 120 determines that the positioning signal from the positioning satellite is normal. The case where the two positions substantially match means, for example, the case where the distance between the two positions is equal to or less than a predetermined value. The predetermined value may be determined according to the accuracy required for positioning.

On the other hand, if the first position and the second position of the same positioning satellite 300 do not match, it is possible that radio waves were transmitted from a transmitter located at a position different from the position obtained from the orbit information. Therefore, the determination unit 120 can determine that the positioning signal from the positioning satellite whose first position and second position do not match is due to spoofing. The determination unit 120 having the above-mentioned function is an example of the determination means.

FIG. 3 is a flowchart showing an operation example of the positioning device 100. As described above, the positioning device 100 calculates the first position indicating the position of the positioning satellite 300 based on the arrival direction of the radio wave from the positioning satellite 300 (step S01 in FIG. 3), and is based on the orbit information. The second position indicating the position of the positioning satellite 300 is calculated (step S02). Then, the positioning device 100 determines the normality of the received positioning signal based on the comparison result between the first position and the second position (step S03). Step S01 and step S02 may be executed in the reverse order. Step S01 and step S02 may be executed in parallel. In this way, the positioning device 100 can determine the normality of the positioning signal transmitted by the positioning satellite 300 for each positioning satellite 300. By not using the positioning signal received from the positioning satellite 300 determined to be abnormal, the positioning device 100 enables more accurate positioning.

(Second Embodiment)
FIG. 4 is a block diagram showing a configuration example of the positioning device 101 according to the second embodiment of the present invention. The positioning device 101 includes a position calculation unit 110 and a determination unit 120 similar to the positioning device 100 of the first embodiment, and further includes an antenna 130 and a demodulation unit 140. The antenna 130 receives the positioning signal from the positioning satellite. Specifically, the antenna 130 receives a radio wave including a positioning signal from a positioning satellite and converts the received radio wave into a high-frequency signal. The demodulation unit 140 demodulates the high frequency signal input from the antenna 130 and extracts the positioning signal. The positioning satellite is the positioning satellite 300 included in the positioning system 10 shown in FIG.

Similar to the first embodiment, the position calculation unit 110 calculates the first position indicating the position of the positioning satellite based on the arrival direction of the radio wave including the positioning signal. The position calculation unit 110 further calculates a second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal. The determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position and the second position. In this embodiment, a specific example of realizing the functions of the position calculation unit 110 and the determination unit 120 will be described.

The operation of the position calculation unit 110 in this embodiment will be described below. The position calculation unit 110 obtains the arrival direction of the radio wave from the positioning satellite received by the antenna 130. In the present embodiment, the procedure for determining the direction of arrival of radio waves is not limited. The position of the positioning satellite on the sky map at the receiving point (antenna 130) of the positioning signal can be obtained from the direction in which the radio wave including the positioning signal arrives (that is, the direction of the positioning satellite that transmitted the positioning signal).

FIG. 5 is a diagram showing an example of a sky map of a positioning satellite obtained from the direction of arrival of radio waves in the present embodiment. The sky map shown in FIG. 5 corresponds to the first position, which is the position of the positioning satellite based on the arrival direction of the radio wave including the positioning signal. That is, FIG. 5 shows an example of the direction of arrival of radio waves from the five positioning satellites X1-X5 (black circles) seen from the antenna 130. The positioning satellites X1-X5 are identified by the positioning signal included in the received radio wave.

On the other hand, the position calculation unit 110 can uniquely calculate the position of the positioning satellite on the sky map at a predetermined position and time based on the orbit information. Therefore, the position calculation unit 110 searches by calculation whether or not a sky map based on the orbit information corresponding to the sky map can exist at the same time when the sky map showing the first position is given. (Ie, calculate).

In the example of the present embodiment, the position calculation unit 110 searches the sky map corresponding to FIG. 5 based on the orbit information when the sky map based on the first position of the positioning satellite is shown in FIG. 6 and 7 are first and second examples of the sky map of the positioning satellite at the same time as FIG. 5 obtained from the orbit information, respectively.

FIG. 6 is a diagram showing a first example of the search result of the sky map (that is, the sky map based on the second position) showing the position of the positioning satellite obtained from the orbit information. FIG. 6 shows that, as a result of the search, it was found that the arrangement of the same positioning satellites X1-X5 (marked with white circles) substantially matches that of FIG.

FIG. 7 is a diagram showing a second example of the search result of the sky map (second position) showing the position of the positioning satellite obtained from the orbit information. In FIGS. 6 and 7, the positioning satellites X1-X5 are identified using orbit information. In FIG. 7, as a result of the search, it was found that the arrangements of the same positioning satellites X1 and X3-X5 (marked with white circles) substantially match those in FIG. On the other hand, in FIG. 7, the positioning satellite X2 does not exist in the sky map. Here, the determination unit 120 obtains the distance between the coordinates of the first position and the coordinates of the searched second position for each positioning satellite, and when the total or average value of the distances is smaller than a predetermined value. May determine that the first position and the second position substantially match. Further, the determination unit 120 may use the sum or average value of the distances as an index of the degree of coincidence between the first position and the second position, and may determine that the smaller the sum or average value is, the higher the degree of coincidence is. ..

The determination unit 120 draws a sky map (FIG. 5, first position) calculated by the position calculation unit 110 from the direction of arrival of radio waves and a sky map (FIG. 6, 7, second position) calculated from the orbit information. Received from the position calculation unit 110 and compared the two. The positions of the positioning satellites X1-X5 in FIG. 5 on the sky map substantially coincide with those in FIG. Therefore, when the sky map of FIG. 6 is searched, the determination unit 120 can determine that the positioning satellites X1-X5 are normal satellites and that the positioning signals received from these satellites are all normal.

On the other hand, the positioning satellite X2 in FIG. 5 does not appear in the sky map in FIG. 7. In such a case, the positioning satellite X2 can be presumed to be a satellite that does not originally exist in light of the orbit information. Therefore, in the determination unit 120, the positioning satellites X1 and X3-X5 are normal satellites, but the signal received as a radio wave from the positioning satellite X2 is abnormal (that is, it may be a spoofing signal). Can be judged.

Even when the positioning satellite X2 appears in the sky map of FIG. 7, the position of the positioning satellite X2 shown in FIG. 7 does not substantially match the position of the positioning satellite X2 shown in FIG. 5 (for example). , When the distance between the two is more than a predetermined distance) is also conceivable. Even in such a case, the positioning satellite X2 in FIG. 5 may be presumed to be a satellite that does not originally exist in light of the orbit information.

If the position calculation unit 110 cannot search for a position that can be determined to match the position of the positioning satellite with the sky map of FIG. 5 based on the orbit information, the position calculation unit 110 indicates the position indicated by another sky map having the next highest degree of matching. The position of the satellite may be the second position.

Further, the determination unit 120 maximizes the degree of agreement with the sky map showing the first position illustrated in FIG. 5 by operating the sky map showing the second position exemplified in FIGS. 6 and 7. In this case, the error in the position or orientation of the positioning device 101 can be estimated according to the amount of operation when the maximum is reached. For example, when the determination unit 120 obtains the maximum value of the degree of coincidence with the sky map showing the first position by rotating the sky map showing the second position, the maximum value is obtained. The amount of rotation and the direction of rotation may be estimated as an error in the orientation of the positioning device 101.

Also, the higher the altitude of the positioning device 101, the more the same positioning satellite is shown in the sky map at a position farther from the center. Therefore, when the sky map showing the second position is enlarged or reduced in a similar manner to obtain the maximum value of the degree of coincidence with the sky map showing the first position, the altitude corresponding to the enlargement amount or the reduction amount is obtained. The difference can be calculated. For example, the determination unit 120 is the difference between the altitude of the initial positioning device 101 in FIG. 6 or FIG. 7 and the altitude of the positioning device 101 obtained from the sky map of FIG. 6 or 7 when the degree of coincidence is maximized. May be estimated as the altitude error of the positioning device 101. The altitude of the positioning device 101 in the sky map showing the second position can be obtained when calculating the second position based on the orbit information.

In addition, when the maximum value of the degree of coincidence can be obtained by translating the sky map showing the second position, the determination unit 120 sets the second position when the maximum value of the degree of coincidence is obtained. The amount of movement of the shown sky map with respect to the sky map showing the initial second position may be estimated as an error in the horizontal position of the positioning device 101.

As described above, when the degree of coincidence between the sky map showing the first position and the sky map showing the second position is increased by the operation of the sky map showing the second position, the determination unit 120 performs the operation. The error of at least one of the direction and position of the positioning device can be estimated based on the quantity. Further, when the degree of coincidence is maximized by combining the above-mentioned operations of rotation, enlargement or reduction, and parallel movement, the determination unit 120 has an directional error, an altitude error, and a horizontal direction in the maximum state. The position error may be obtained for each type of operation. In the sky map of FIG. 6 or FIG. 7 obtained from the orbit information, when the receiving position of the positioning signal (that is, the position of the antenna 130) is clearly different from the actual position of the antenna 130, the first position and the first position There may be an abnormality in one of the two positions. For example, if the positioning device 101 is mounted on an aircraft flying at high altitude but the reception position in the sky map of FIG. 6 or 7 is calculated to be on the ground, there is an abnormality in the positioning signal. there is a possibility. When there is an obvious abnormality in the calculation result, the position calculation unit 110 uses the direction of arrival of radio waves from other positioning satellites and the orbit information extracted from the other positioning satellites to obtain the first position and The second position may be recalculated. Further, even if it can be determined that there is no abnormality in the calculation result, the position calculation unit 110 further uses the arrival direction of the radio wave from the other positioning satellite and the orbit information extracted from the other positioning satellite to make the first position. The position and the second position may be recalculated.

The first position illustrated in FIG. 5 is calculated only from the direction of arrival of radio waves. Therefore, if a spoofing signal is transmitted from the same direction as a legitimate positioning satellite, spoofing may not be detected. Therefore, the position calculation unit 110 may obtain a pseudo distance to the positioning satellite based on the positioning signal received by the antenna 130. The pseudo distance is a distance between the positioning satellite and the positioning device 101, which is obtained from the difference between the transmission time of the positioning signal on the positioning satellite and the reception time of the positioning signal on the positioning device 101. If it cannot be determined that the distance between the positioning satellite and the antenna 130 obtained from the orbit information and the pseudo distance match, the determination unit 120 has a pseudo distance different from the pseudo distance obtained from the orbit information. The positioning signal from the satellite may be determined to be a spoofing signal.

Further, the position calculation unit 110 may obtain the relative position between the positioning satellites based on the received radio wave as the first position by acquiring the arrival direction of the radio wave and its pseudo distance for three or more positioning satellites. .. Then, the determination unit 120 may compare the first position with the second position obtained by searching as a relative position between the corresponding positioning satellites based on the orbit information.

FIG. 8 is a flowchart showing an operation example of the positioning device 101. As described above, the antenna 130 receives the positioning signal from the positioning satellite (step S11 in FIG. 8). The demodulation unit 140 demodulates the positioning signal (step S12). The position calculation unit 110 calculates a first position indicating the position of the positioning satellite obtained based on the arrival direction of the radio wave (step S13). Then, the position calculation unit 110 calculates a second position corresponding to the first position, which indicates the position of the positioning satellite based on the orbit information (step S14). The determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position and the second position (step S15).

The positioning device 101 having such a configuration also determines the normality of the positioning signal by comparing the position of the positioning satellite obtained based on the propagation direction of the radio wave with the position of the positioning satellite obtained from the orbit information. can. Therefore, the positioning device 101 can also detect the spoofing of the positioning signal transmitted by the positioning satellite.

Further, according to the procedure of the present embodiment, the position information of the positioning device 101 is not required to calculate the first position and the second position indicating the position of the positioning satellite. Further, the positioning device 101 does not need to use other positioning methods such as inertial navigation and Doppler navigation.

(Third Embodiment)
FIG. 9 is a block diagram showing a configuration example of the positioning device 102 according to the third embodiment of the present invention. The positioning device 102 includes a position calculation unit 110, a determination unit 120, and a demodulation unit 140, similarly to the positioning device 101 of the second embodiment. Further, the positioning device 102 includes a plurality of antennas 130. Each of the antennas 130 may be an omnidirectional antenna. When the positioning device 102 is mounted on an aircraft, the antennas 130 are arranged at a total of four locations, for example, the front and rear ends of the airframe and the tips of both wings. The position calculation unit 110, the determination unit 120, and the demodulation unit 140 may be housed in one equipment room of the aircraft. The antenna 130 and the demodulation unit 140 may be connected by a high frequency line such as a coaxial cable.

The antenna 130 receives radio waves including a positioning signal from a positioning satellite. High-frequency signals including positioning signals are input to the demodulation unit 140 from each of the antennas 130. The demodulation unit 140 demodulates the positioning signal from each high frequency signal. Further, the demodulation unit 140 calculates the phase difference of the radio waves between the plurality of antennas 130 when the radio waves from the positioning satellites are received for each positioning satellite that is the source of the radio waves. The delay time between each of the antennas 130 and the demodulation unit 140 can be calculated or measured in advance. Therefore, the demodulation unit 140 can obtain the phase difference between the antennas 130 at the time of receiving the radio wave by considering the delay time. The demodulation unit 140 outputs the demodulated positioning signal to the first calculation unit 111 and the second calculation unit 112, and outputs the obtained phase difference to the first calculation unit 111.

The first calculation unit 111 includes a function of calculating the first position indicating the position of the positioning satellite based on the arrival direction of the radio wave among the functions of the position calculation unit 110 described in the first and second embodiments. .. If the relative positions between the plurality of antennas 130 are known, the arrival direction of the radio waves can be determined by a well-known procedure based on the phase difference of the radio waves received by each of the antennas 130. Therefore, the first calculation unit 111 can calculate the position of the positioning satellite of the source of the radio wave for each positioning satellite based on the arrival direction of the radio wave. The first position can be obtained by drawing the position of the positioning satellite calculated in this way on the sky map. The demodulation unit 140 may output the reception time difference of the radio waves of each of the antennas 130 to the first calculation unit 111 instead of the phase difference of the radio waves received by each of the antennas 130. In this case, the first calculation unit 111 calculates the first position based on the reception time difference.

The second calculation unit 112 includes a function of calculating a second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite among the functions of the position calculation unit 110 described in the first and second embodiments. .. For example, the second calculation unit 112 calculates the sky map showing the position of the positioning satellite based on the orbit information as the second position according to the procedure described in the second embodiment.

Then, the determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position and the second position according to the procedure described in the first embodiment or the second embodiment. judge.

The positioning device 102 having such a configuration calculates the position (first position) of the positioning satellite obtained from the phase difference or reception time difference of the radio waves between the antennas 130 when receiving the radio waves from the positioning satellite, and also calculates the position (first position) of the positioning satellite. The position (second position) of the positioning satellite obtained from the orbit information is calculated. Then, the positioning device 102 determines the normality of the positioning signal based on the comparison result between the first direction which is the arrival direction of the positioning signal and the second direction which is the direction of the positioning satellite obtained from the orbit information. .. Therefore, the positioning device 102 can also detect the spoofing of the signal transmitted by the positioning satellite.

(Fourth Embodiment)
FIG. 10 is a block diagram showing a configuration example of the positioning device 103 according to the fourth embodiment of the present invention. The positioning device 103 includes a plurality of demodulation units 141 instead of the demodulation unit 140, as compared with the positioning device 102 of the third embodiment. The demodulation unit 141 is a receiver that demodulates the positioning signal, and is arranged for each antenna 130. Further, the position calculation unit 110A of the positioning device 103 includes a first calculation unit 111A and a second calculation unit 112.

The antenna 130 receives a radio wave including a positioning signal and converts it into a high frequency signal. The demodulation unit 141 demodulates the high-frequency signal input from the antenna 130, and outputs the positioning signal received by the antenna 130 and the reception phase of the radio wave at the antenna 130 or the reception time of the radio wave to the position calculation unit 110.

More specifically, the demodulation unit 141 obtains at least one of the phase of the radio wave and the reception time of the radio wave in the connected antenna 130, and outputs the positioning signal to the first calculation unit 111A. Further, the demodulation unit 141 demodulates the positioning signal from the high frequency signal input from the antenna 130, and outputs the demodulated positioning signal to the second calculation unit 112. By controlling each of the demodulation units 141 with the same clock and compensating for the delay in wiring between each of the antennas 130 and the position calculation unit 110A, the first calculation unit 111A between the antennas 130 at the same time. The phase difference and the reception time difference can be obtained. The first calculation unit 111A can calculate the position (first position) of the positioning satellite based on these phase differences or reception time differences.

The other processing in the position calculation unit 110A and the processing in the determination unit 120 may be the same as those in the positioning device 102 according to any one of the first to third embodiments. The determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position and the second position calculated by the position calculation unit 110A. Therefore, the positioning device 103 can also detect the spoofing of the signal transmitted by the positioning satellite.

Further, in the positioning device 103, since the demodulation unit 141 is provided for each antenna 130, the demodulation unit can be arranged in the vicinity of the antenna 130 even if the positions of the antennas 130 are separated from each other. As a result, the loss of the high frequency signal between the antenna 130 and the demodulation unit 141 can be reduced, so that the quality deterioration of the signal received from the positioning satellite can be suppressed.

(Fifth Embodiment)
FIG. 11 is a block diagram showing a configuration example of the positioning device 104 according to the fifth embodiment. The positioning device 104 includes a directional antenna 130A, a demodulation unit 140, a position calculation unit 110B, and a determination unit 120. The position calculation unit 110B is different from the position calculation unit 110 of the third embodiment in that the position calculation unit 110B includes the first calculation unit 111B. The directional antenna 130A is an antenna capable of externally controlling the direction in which the gain of the received radio wave is maximized (hereinafter, referred to as “reception direction”), and is, for example, an array antenna or a parabolic antenna. The first calculation unit 111B has a function of controlling the reception direction of the directional antenna 130A in addition to the function of the first calculation unit 111. The first calculation unit 111B sets the reception direction in which the intensity of the radio wave received from the positioning satellite by the directional antenna 130A is maximum as the arrival direction of the radio wave including the positioning signal. The demodulation unit 140 may be arranged in the vicinity of the directional antenna 130A. By using the directional antenna 130A, the positioning device 104 can know the arrival direction of the radio wave without using the phase difference between the plurality of antennas.

The processing other than the directivity control function of the directional antenna 130A in the first calculation unit 111B is the same as that of the positioning device 102 according to any one of the first to fourth embodiments. Further, the processing of the second calculation unit 112 and the determination unit 120 is the same as that of the positioning device 102 according to any one of the first to fourth embodiments. The determination unit 120 determines the normality of the received positioning signal based on the comparison result between the first position calculated by the first calculation unit 111B and the second position calculated by the second calculation unit 112. do. Therefore, the positioning device 104 can also detect the spoofing of the signal transmitted by the positioning satellite.

(Sixth Embodiment)
FIG. 12 is a block diagram showing a configuration example of the positioning device 105 according to the sixth embodiment of the present invention. The positioning device 105 further includes an output unit 150 in addition to the configuration of the positioning device 101 of the second embodiment.

The determination unit 120 outputs the determination result of normality between the first position and the second position. The output unit 150 is an example of an output means that outputs the determination result output by the determination unit 120 at least one of the image and the sound. For example, the output unit 150 is a terminal including at least one of a display and a speaker. When the determination unit 120 determines that the positioning signal is normal, the output unit 150 displays on the display that the positioning signal is normal, or outputs a voice indicating that the positioning signal is normal from the speaker. .. On the other hand, when the determination unit 120 determines that the positioning signal is abnormal, the output unit 150 displays on the display that the positioning signal is abnormal, or indicates from the speaker that the positioning signal is abnormal. Output as audio. The output from the output unit 150 is not limited to images and sounds. The output unit 150 may send the determination result of the determination unit 120 to a default destination by e-mail.

The positioning device 105 having such a configuration can detect spoofing of a signal transmitted by a positioning satellite and can notify the determination result of the determination unit 120 in a more specific form. The same effect can be obtained when the output unit 150 is provided in any of the positioning devices according to the first, third, fourth, and fifth embodiments.

The embodiment of the present invention may be described as in the following appendix, but is not limited thereto.

(Appendix 1)
The first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal is calculated, and the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal is calculated. A position calculation means for calculating the second position shown, and
A determination means for determining the normality of the received positioning signal based on the comparison result between the first position and the second position, and
Positioning device equipped with.

(Appendix 2)
It is equipped with an antenna that receives the positioning signal.
The positioning satellite is one of a plurality of positioning satellites that can be received by the antenna.
The position calculation means calculates the first position and the second position for each of the plurality of positioning satellites.
The determination means determines the normality of the positioning signal for each of the plurality of positioning satellites based on the comparison result between the first position and the second position of each of the plurality of positioning satellites.
The positioning device according to Appendix 1.

(Appendix 3)
The antenna is one of a plurality of antennas.
The position calculating means has the plurality of positioning satellites based on the arrival direction of the radio wave obtained based on at least one of the phase difference at the time of receiving the radio wave and the reception time difference of the radio wave between the plurality of antennas. The positioning device according to Appendix 2, which calculates the first position for each.

(Appendix 4)
The antenna is an antenna having a variable receiving direction.
The position calculation means is the first position for each of the plurality of positioning satellites based on the arrival direction of the radio wave including the positioning signal obtained based on the reception direction of the antenna that maximizes the reception intensity of the radio wave. The positioning device according to Appendix 2, which calculates.

(Appendix 5)
The positioning device according to any one of Supplementary Provisions 1 to 4, wherein the first position and the second position are represented as positions on the sky map of the positioning satellite.

(Appendix 6)
The determination means is based on the amount of the operation when the degree of agreement between the sky map showing the first position and the sky map showing the second position is increased by the operation of the sky map showing the second position. The positioning device according to Appendix 5, which estimates an error in at least one of the direction and the position of the positioning device.

(Appendix 7)
When the maximum value of the degree of coincidence is obtained by the operation of rotating the sky map showing the second position, the determination means of the sky map showing the second position when the maximum value is obtained. The positioning device according to Appendix 6, which estimates the amount of rotation as an error in the orientation of the positioning device.

(Appendix 8)
The determination means indicates the second position before the operation when the maximum value of the degree of coincidence is obtained by the operation of expanding or contracting the sky map showing the second position in a similar manner. The difference between the altitude of the positioning device obtained from the sky map and the altitude of the positioning device obtained from the sky map indicating the second position when the maximum value is obtained is estimated as an error in the altitude of the positioning device. , The positioning apparatus according to Appendix 6 or 7.

(Appendix 9)
When the maximum value of the degree of coincidence is obtained by the operation of translating the sky map showing the second position, the determination means shows the sky map showing the second position for obtaining the maximum value. The positioning device according to any one of Appendix 6 to 8, wherein the amount of translation of the above is estimated as an error in the horizontal position of the positioning device.

(Appendix 10)
The positioning device according to any one of Supplementary Provisions 1 to 9, wherein the position calculating means further calculates the first position based on a pseudo distance obtained from the positioning signal.

(Appendix 11)
The determination means outputs a determination result that the positioning signal is abnormal if the difference between the first position and the second position exceeds a predetermined range. The positioning device according to item 1.

(Appendix 12)
The positioning apparatus according to any one of Supplementary note 1 to 11, further comprising a demodulation means for extracting the positioning signal from a high-frequency current generated from the radio wave.

(Appendix 13)
The positioning apparatus according to any one of Supplementary note 1 to 12, further comprising an output means for outputting the comparison result on at least one of an image and an audio.

(Appendix 14)
The positioning device according to any one of Appendix 1 to 13, wherein the positioning signal is a signal transmitted from at least one of a GNSS satellite and an SBAS satellite.

(Appendix 15)
With multiple positioning satellites
The positioning device according to any one of Appendix 1 to 10, which performs positioning by receiving positioning signals from the plurality of positioning satellites.
Positioning system equipped with.

(Appendix 16)
Calculate the first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal is calculated.
Based on the comparison result between the first position and the second position, the normality of the received positioning signal is determined.
Positioning method.

(Appendix 17)
The positioning signal is received from a plurality of the positioning satellites by the antenna, and the positioning signal is received.
The first position and the second position are calculated for each of the plurality of positioning satellites.
The normality of the positioning signal is determined for each of the plurality of positioning satellites based on the comparison result between the first position of each of the plurality of positioning satellites and the second position.
The positioning method described in Appendix 16.

(Appendix 18)
For each of the plurality of positioning satellites, the first The positioning method according to Appendix 17, which calculates a position.

(Appendix 19)
Appendix 17 Calculates the first position for each of the plurality of positioning satellites based on the arrival direction of the radio wave including the positioning signal obtained based on the reception direction of the antenna that maximizes the reception intensity of the radio wave. The positioning method described in.

(Appendix 20)
The positioning method according to any one of Appendix 16 to 19, wherein the first position and the second position are expressed as positions on the sky map of the positioning satellite.

(Appendix 21)
The direction of the positioning device based on the amount of the operation when the degree of agreement between the sky map showing the first position and the sky map showing the second position is increased by the operation of the sky map showing the second position. And the positioning method according to Appendix 20, which estimates an error in at least one of the positions.

(Appendix 22)
When the maximum value of the degree of coincidence is obtained by the operation of rotating the sky map showing the second position, the amount of rotation of the sky map showing the second position when the maximum value is obtained is calculated as described above. The positioning method according to Appendix 21, which is estimated to be an error in the orientation of the positioning device.

(Appendix 23)
When the maximum value of the degree of coincidence is obtained by the operation of enlarging or reducing the sky map showing the second position in a similar manner, the sky map showing the second position before the operation can be obtained. Appendix 21 or 22 that the difference between the altitude of the positioning device and the altitude of the positioning device obtained from the sky map showing the second position when the maximum value is obtained is estimated as the error of the altitude of the positioning device. The positioning method described in.

(Appendix 24)
When the maximum value of the degree of coincidence is obtained by the operation of translating the sky map showing the second position, the amount of translation of the sky map showing the second position for obtaining the maximum value is calculated. The positioning method according to any one of Appendix 21 to 23, which is estimated to be an error in the position of the positioning device in the horizontal direction.

(Appendix 25)
Further, the positioning method according to any one of Appendix 16 to 24, wherein the first position is calculated based on the pseudo distance obtained from the positioning signal.

(Appendix 26)
It is described in any one of Appendix 16 to 25, which outputs a determination result that the positioning signal is abnormal if the difference between the first position and the second position exceeds a predetermined range. Positioning method.

(Appendix 27)
The positioning method according to any one of Appendix 16 to 26, wherein the positioning signal is extracted from a high-frequency current generated from the radio wave.

(Appendix 28)
The positioning method according to any one of Appendix 16 to 27, wherein the comparison result is output at least one of an image and an audio.

(Appendix 29)
The positioning method according to any one of Appendix 16 to 28, wherein the positioning signal is a signal transmitted from at least one of a GNSS satellite and an SBAS satellite.

(Appendix 30)
To the computer of the positioning device
A procedure for calculating a first position indicating the position of a positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A procedure for calculating a second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal.
A procedure for determining the normality of the received positioning signal based on the comparison result between the first position and the second position.
A recording medium on which a positioning program for executing is recorded.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the structure and details of the present invention within the scope of the present invention.

Moreover, the configurations described in the respective embodiments are not necessarily exclusive to each other. The constitution, action and effect of the present invention may be realized by a combination of all or a part of the above-described embodiments.

The functions and procedures described in each of the above embodiments may be realized by executing a program by a central processing unit (CPU) included in each positioning device. The program is recorded on a fixed, non-transitory recording medium. A semiconductor memory or a fixed magnetic disk device is used as the recording medium, but the recording medium is not limited thereto. The CPU is, for example, a computer provided in the position calculation unit of each embodiment.

10 Positioning system 100-105

Positioning device

110, 110A, 110B Position calculation unit 111, 111A, 111B 1st calculation unit 112 2nd calculation unit 120 Judgment unit 130 Antenna 130A Directional antenna 140, 141 Demodulation unit 150 Output unit 200 Mobile 300 positioning satellite

Claims

The first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal is calculated, and the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal is calculated. A position calculation means for calculating the second position shown, and
A determination means for determining the normality of the received positioning signal based on the comparison result between the first position and the second position, and
Positioning device equipped with.
It is equipped with an antenna that receives the positioning signal.
The positioning satellite is one of a plurality of positioning satellites that can be received by the antenna.
The position calculation means calculates the first position and the second position for each of the plurality of positioning satellites.
The determination means determines the normality of the positioning signal for each of the plurality of positioning satellites based on the comparison result between the first position and the second position of each of the plurality of positioning satellites.
The positioning device according to claim 1.
The antenna is one of a plurality of antennas.
The position calculating means has the plurality of positioning satellites based on the arrival direction of the radio wave obtained based on at least one of the phase difference at the time of receiving the radio wave and the reception time difference of the radio wave between the plurality of antennas. The positioning device according to claim 2, wherein the first position is calculated for each.
The antenna is an antenna having a variable receiving direction.
The position calculation means is the first position for each of the plurality of positioning satellites based on the arrival direction of the radio wave including the positioning signal obtained based on the reception direction of the antenna that maximizes the reception intensity of the radio wave. 2. The positioning device according to claim 2.
The positioning device according to any one of claims 1 to 4, wherein the first position and the second position are represented as positions on the sky map of the positioning satellite.
The determination means is based on the amount of the operation when the degree of agreement between the sky map showing the first position and the sky map showing the second position is increased by the operation of the sky map showing the second position. The positioning device according to claim 5, wherein an error of at least one of the direction and the position of the positioning device is estimated.
When the maximum value of the degree of coincidence is obtained by the operation of rotating the sky map showing the second position, the determination means of the sky map showing the second position when the maximum value is obtained. The positioning device according to claim 6, wherein the amount of rotation is estimated as an error in the orientation of the positioning device.
The determination means indicates the second position before the operation when the maximum value of the degree of coincidence is obtained by the operation of expanding or contracting the sky map showing the second position in a similar manner. The difference between the altitude of the positioning device obtained from the sky map and the altitude of the positioning device obtained from the sky map indicating the second position when the maximum value is obtained is estimated as an error in the altitude of the positioning device. , The positioning apparatus according to claim 6 or 7.
When the maximum value of the degree of coincidence is obtained by the operation of translating the sky map showing the second position, the determination means shows the sky map showing the second position for obtaining the maximum value. The positioning device according to any one of claims 6 to 8, wherein the amount of translation of the above is estimated as an error in the position of the positioning device in the horizontal direction.
The positioning device according to any one of claims 1 to 9, wherein the position calculating means further calculates the first position based on a pseudo distance obtained from the positioning signal.
Any of claims 1 to 10, wherein the determination means outputs a determination result that the positioning signal is abnormal if the difference between the first position and the second position exceeds a predetermined range. The positioning device according to item 1.
The positioning device according to any one of claims 1 to 11, further comprising a demodulation means for extracting the positioning signal from a high-frequency current generated from the radio wave.
The positioning apparatus according to any one of claims 1 to 12, further comprising an output means for outputting the comparison result on at least one of an image and an audio.
The positioning device according to any one of claims 1 to 13, wherein the positioning signal is a signal transmitted from at least one of a GNSS satellite and an SBAS satellite.
With multiple positioning satellites
The positioning device according to any one of claims 1 to 14, which performs positioning by receiving positioning signals from the plurality of positioning satellites.
Positioning system equipped with.
Calculate the first position indicating the position of the positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal is calculated.
Based on the comparison result between the first position and the second position, the normality of the received positioning signal is determined.
Positioning method.
The positioning signal is received from a plurality of the positioning satellites by the antenna, and the positioning signal is received.
The first position and the second position are calculated for each of the plurality of positioning satellites.
The normality of the positioning signal is determined for each of the plurality of positioning satellites based on the comparison result between the first position of each of the plurality of positioning satellites and the second position.
The positioning method according to claim 16.
The first for each of the plurality of positioning satellites based on the arrival direction of the radio wave obtained based on at least one of the phase difference at the time of receiving the radio wave and the reception time difference of the radio wave between the plurality of antennas. The positioning method according to claim 17, wherein the position is calculated.
The first position is calculated for each of the plurality of positioning satellites based on the arrival direction of the radio wave including the positioning signal obtained based on the reception direction of the antenna that maximizes the reception strength of the radio wave. 17. The positioning method according to 17.
The positioning method according to any one of claims 16 to 19, wherein the first position and the second position are expressed as positions on the sky map of the positioning satellite.
The direction of the positioning device based on the amount of the operation when the degree of agreement between the sky map showing the first position and the sky map showing the second position is increased by the operation of the sky map showing the second position. The positioning method according to claim 20, wherein the error of at least one of the position and the position is estimated.
When the maximum value of the degree of coincidence is obtained by the operation of rotating the sky map showing the second position, the amount of rotation of the sky map showing the second position when the maximum value is obtained is calculated as described above. The positioning method according to claim 21, which is estimated to be an error in the orientation of the positioning device.
When the maximum value of the degree of coincidence can be obtained by the operation of enlarging or reducing the sky map showing the second position in a similar manner, the sky map showing the second position before the operation can be obtained. 21. The positioning method according to 22.
When the maximum value of the degree of coincidence is obtained by the operation of translating the sky map showing the second position, the amount of translation of the sky map showing the second position for obtaining the maximum value is calculated. The positioning method according to any one of claims 21 to 23, which is estimated to be an error in the position of the positioning device in the horizontal direction.
The positioning method according to any one of claims 16 to 24, further, which calculates the first position based on the pseudo distance obtained from the positioning signal.
The invention according to any one of claims 16 to 25, wherein if the difference between the first position and the second position exceeds a predetermined range, a determination result that the positioning signal is abnormal is output. Positioning method.
The positioning method according to any one of claims 16 to 26, wherein the positioning signal is extracted from a high-frequency current generated from the radio wave.
The positioning method according to any one of claims 16 to 27, which outputs the comparison result at least one of an image and an audio.
The positioning method according to any one of claims 16 to 28, wherein the positioning signal is a signal transmitted from at least one of a GNSS satellite and an SBAS satellite.
To the computer of the positioning device
A procedure for calculating a first position indicating the position of a positioning satellite that transmitted the radio wave based on the arrival direction of the radio wave including the positioning signal.
A procedure for calculating a second position indicating the position of the positioning satellite based on the orbit information of the positioning satellite included in the positioning signal.
A procedure for determining the normality of the received positioning signal based on the comparison result between the first position and the second position.
A recording medium on which a positioning program for executing is recorded.