JP6753400B2 - Positioning equipment, positioning system and positioning method - Google Patents

Description

The present invention relates to a positioning device, a positioning system and a positioning method.

Various techniques for positioning using data transmitted from a GPS (Global Positioning System) satellite have been proposed. For example, Patent Document 1 discloses a technique in which a user station performs high-precision positioning based on a positioning signal received from a navigation satellite and correction information received from a master station. However, in Non-Patent Document 1, it is reported that the positioning accuracy in GPS depends on the state of the ionosphere through which the positioning signal passes.

Japanese Unexamined Patent Publication No. 2011-203100

T. Sakai, ‘’ Dual Frequency Trial and Preliminary Results (Work Plan: Identity Benefits) ”SBAS IWG / 26, New Delhi India, Feb. 5-7, 2014.

Since the technique disclosed in Patent Document 1 does not consider the state of the ionosphere, there is room for improvement in GPS positioning accuracy.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a positioning device, a positioning system, and a positioning method capable of improving GPS positioning accuracy.

In order to achieve the above object, the positioning device according to one aspect of the present invention obtains the first positioning result based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal. The second positioning result is output based on the first positioning means to be output, the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal. Select either the first positioning result or the second positioning result based on the comparison result between the second positioning means and the output first positioning result and the output second positioning result. It is characterized in that it includes a determination means for outputting as positioning information.

In order to achieve the above object, the positioning system according to one aspect of the present invention includes the above-mentioned positioning device further provided with a communication means for receiving the first correction information and the second correction information, and the above-mentioned positioning device and the first. The control device for transmitting the correction information 1 and the correction information 2 is provided.

In order to achieve the above object, the positioning method according to one aspect of the present invention obtains the first positioning result based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal. Output, the second positioning result is output based on the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal, and the output second Based on the comparison result between the positioning result of 1 and the output second positioning result, one of the first positioning result and the second positioning result is selected and output as positioning information. To do.

According to the present invention, the GPS positioning accuracy can be improved.

This is an example of a block configuration diagram of the positioning device 10 according to the first embodiment of the present invention. This is an example of an operation procedure in which the positioning device 10 according to the first embodiment of the present invention determines a positioning means. This is an example of a system configuration diagram of the positioning system 100 according to the second embodiment of the present invention. This is an example of a block configuration diagram of the master station 400 according to the second embodiment of the present invention. This is an example of a block configuration diagram of the user station 500 according to the second embodiment of the present invention. It is a graph which shows the positioning result when the ionosphere is in a quiet state, and the positioning result when the ionosphere is in a disturbed state. This is an example of an operation procedure in which the user station 500 according to the second embodiment of the present invention determines a positioning method.

(First Embodiment)
A first embodiment of the present invention will be described. A block configuration diagram of the positioning device 10 according to this embodiment is shown in FIG. As shown in FIG. 1, the positioning device 10 includes a first positioning means 11, a second positioning means 12, and a determination means 13.

The first positioning means 11 generates a first positioning result based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal, and generates the generated first positioning result. Output to the determination means 13. Here, the first positioning means 11 receives, for example, the first positioning signal from the GPS satellite. Further, the first positioning means 11 receives, for example, the first correction information from a control station (not shown).

The first positioning result includes a first position information indicating the result of positioning based on the first positioning signal and a position obtained by correcting the position indicated by the first position information based on the first correction information. Includes the first corrected position information shown.

The second positioning means 12 generates and generates a second positioning result based on the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal. The second positioning result is output to the determination means 13. Here, the second positioning means 12 receives, for example, the first positioning signal and the second positioning signal from the GPS satellite. Further, the second positioning means 12 receives, for example, the second correction information from a control station (not shown).

In the second positioning result, the second position information indicating the result of the positioning based on the first positioning signal and the second positioning signal and the position indicated by the second position information are used as the second correction information. Includes a second corrected position information indicating the corrected position based on.

The determination means 13 is a first positioning result or a first positioning result based on a comparison result between the first positioning result input from the first positioning means 11 and the second positioning result input from the second positioning means 12. One of the second positioning results is selected and output as positioning information. The determining means 13 calculates, for example, the first measurement error from the first positioning signal and the first correction information, and further calculates the second measurement error from the second positioning signal and the second correction information. , Either the first positioning result or the second positioning result is selected based on the magnitude of the difference between the calculated first measurement error and the second measurement error.

Specifically, the first measurement error is, for example, the distance between the position indicated by the first position information and the position indicated by the first corrected position information. The second measurement error is, for example, the distance between the position indicated by the second position information and the position indicated by the second corrected position information.

Next, the operation procedure when the positioning device 10 outputs the positioning information will be described with reference to FIG. In FIG. 2, the first positioning means 11 generates a first positioning result based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal, and the generated first The positioning result of is output to the determination means 13 (S101).

On the other hand, the second positioning means 12 generates a second positioning result based on the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal. The generated second positioning result is output to the determination means 13 (S102).

The determination means 13 determines the first positioning result based on the comparison result between the first positioning result input from the first positioning means 11 and the second positioning result input from the second positioning means 12. Alternatively, one of the second positioning results is selected and output as positioning information (S103).

In S103, the determination means 13 uses, for example, a first measurement error calculated from the first positioning signal and the first correction information, and a second measurement error calculated from the second positioning signal and the second correction information. If the difference from is less than 1 m, the first positioning result is selected, and if the difference is 1 m or more, the second positioning result is selected.

According to the above configuration, the positioning device 10 according to the present embodiment is a comparison result between the first positioning result input from the first positioning means 11 and the second positioning result input from the second positioning means 12. Based on, either the first positioning result or the second positioning result is selected and output as positioning information.

Therefore, according to the present embodiment, the GPS positioning accuracy can be improved.

(Second embodiment)
A second embodiment will be described. A system configuration diagram of the positioning system 100 according to the present embodiment is shown in FIG. As shown in FIG. 3, the positioning system 100 includes a navigation satellite 200, a monitor station 300, a master station 400, and a user station 500. The positioning system 100 is a system for improving the positioning accuracy of the user station 500, and is, for example, a geostationary satellite type satellite navigation augmentation system (hereinafter referred to as “SBAS”).

The navigation satellite 200 is, for example, a GPS satellite. The navigation satellite 200 transmits positioning signals to the monitor station 300 and the user station 500 at frequencies of the L1 band (1575.42 MHz) and the L5 band (1176.45 MHz), respectively. In the following description, the positioning signal transmitted by the navigation satellite 200 to the monitor station 300 and the user station 500 in the L1 band is referred to as an “L1 positioning signal”. Further, the positioning signal transmitted by the navigation satellite 200 to the monitor station 300 and the user station 500 in the L5 band is referred to as an "L5 positioning signal". Here, it is desirable that there are three or more navigation satellites 200.

The monitor station 300 is, for example, an antenna such as a parabolic antenna installed on the ground. The monitor station 300 receives the L1 positioning signal and the L5 positioning signal. Then, the monitor station 300 transmits the data included in the received positioning signal (hereinafter, referred to as “positioning data”) to the master station 400. Here, the positioning data is data including, for example, the transmission time of the L1 positioning signal and the L5 positioning signal, the orbit information of the navigation satellite 200, and the like. The monitor station 300 receives the L1 positioning signal and the L5 positioning signal by using, for example, a dual-frequency GPS receiver.

The master station 400 is, for example, a navigation control station. The master station 400 transmits information for correcting the GPS positioning error (hereinafter, referred to as “error correction information”) to the user station 500. The error correction information is grid information, trajectory correction information, and clock correction information, which will be described later. For example, as shown in FIG. 4, the master station 400 includes a communication unit 401, an ionospheric delay calculation unit 402, a grid information generation unit 403, an orbit correction information generation unit 404, and a clock correction information generation unit 405. Be prepared.

The communication unit 401 receives the positioning data transmitted from the monitor station 300. Further, the communication unit 401 obtains error correction information of grid information generated by the grid information generation unit 403, trajectory correction information generated by the trajectory correction information generation unit 404, and clock correction information generated by the clock correction information generation unit 405. Is transmitted to the user station 500 via a geostationary satellite (not shown).

The ionospheric delay calculation unit 402 calculates the ionospheric delay based on the positioning data received by the communication unit 401. Here, the ionospheric delay is a delay that occurs when the L1 positioning signal or the L5 positioning signal transmitted from the navigation satellite 200 passes through the ionosphere.

The grid information generation unit 403 calculates the ionospheric delay at the ionospheric grid point (hereinafter, referred to as “IGP”) based on the ionospheric delay calculated by the ionospheric delay calculation unit 402. Then, the grid information generation unit 403 generates "grid information" which is information for correcting the ionospheric delay in the calculated IGP. Here, for example, the IGP is set every 5 degrees in latitude and longitude.

The orbit correction information generation unit 404 generates "orbit correction information" which is information for correcting the orbit of the navigation satellite 200 based on the positioning data received by the communication unit 401.

The clock correction information generation unit 405 generates "clock correction information" which is information for correcting the clock of the positioning signal transmitted from the navigation satellite 200.

The user station 500 is, for example, an aircraft. The user station 500 is positioned by a method having higher positioning accuracy among positioning by one frequency (hereinafter, referred to as "one frequency positioning") and positioning by two frequencies (hereinafter, referred to as "two frequency positioning"). I do. Here, the one-frequency positioning is a method of performing positioning based on the L1 positioning signal and the error correction information transmitted from the master station 400. Further, the dual frequency positioning is a method of performing positioning based on the L1 positioning signal, the L5 positioning signal, and the error correction information transmitted from the master station 400. The user station 500 normally performs 1-frequency positioning, and when the difference between the positioning error of the first positioning result and the positioning error of the second positioning result, which will be described later, satisfies a predetermined condition, the 1-frequency positioning is performed. Change from to dual frequency positioning.

A block configuration diagram of the user station 500 according to this embodiment is shown in FIG. In FIG. 5, the user station 500 includes a communication unit 501, a first positioning unit 502, a second positioning unit 503, and a positioning determination unit 504.

The communication unit 501 receives the L1 positioning signal, the L5 positioning signal, and the error correction information transmitted from the master station 400. Here, the communication unit 501 receives the L1 positioning signal and the L5 positioning signal by using, for example, a dual-frequency GPS receiver. Further, the communication unit 501 receives the error correction information from the master station 400 via a geostationary satellite (not shown).

The first positioning unit 502 performs one-frequency positioning based on the L1 positioning signal and the error correction information transmitted from the master station 400. Then, the first positioning unit 502 outputs the result of the one-frequency positioning as the first positioning result to the positioning determination unit 504.

The first positioning result includes the first position information indicating the result of positioning based on the L1 positioning signal and the first position indicating the position indicated by the first position information corrected based on the error correction information. The corrected position information of is included.

The second positioning unit 503 performs dual frequency positioning based on the L1 positioning signal, the L5 positioning signal, and the error correction information transmitted from the master station 400. Then, the second positioning unit 503 outputs the result of the dual frequency positioning as the second positioning result to the positioning determination unit 504.

The second positioning result includes a second position information indicating the result of positioning based on the L1 positioning signal and the L5 positioning signal, and a position obtained by correcting the position indicated by the second position information based on the error correction information. The second corrected position information indicating the above is included.

The positioning determination unit 504 calculates the positioning error of the first positioning result from the L1 positioning signal and the error correction information, and calculates the positioning error of the second positioning result from the L1 positioning signal, the L5 positioning signal and the error correction information. ..

Specifically, the positioning determination unit 504 calculates, for example, the distance between the position indicated by the first position information and the position indicated by the first corrected position information as the positioning error of the first positioning result. To do. Further, the positioning determination unit 504 calculates, for example, the distance between the position indicated by the second position information and the position indicated by the second corrected position information as the positioning error of the second positioning result.

Then, the positioning determination unit 504 determines the first positioning result input from the first positioning unit 502 based on the magnitude of the difference between the calculated positioning error of the first positioning result and the positioning error of the second positioning result. And one of the second positioning results input from the second positioning unit 503 is selected and output as the positioning information of the user station 500.

Here, an example of the positioning error of the first positioning result and the positioning error of the second positioning result is shown in FIG.

In addition, in FIG. 6, each positioning error is expressed by a distance.

FIG. 6A shows an example of the positioning error of the first positioning result and the positioning error of the second positioning result when the ionosphere is in the static state, and FIG. 6B shows the first positioning when the ionosphere is in the disturbed state. It is an example of the positioning error of the result and the positioning error of the second positioning result. Note that FIGS. 6A and 6B are graphs of positioning errors disclosed in Non-Patent Document 1 with processing required by the inventor. In FIGS. 6 (A) and 6 (B), the horizontal axis is a number assigned by arranging the positioning points arranged in Japan from north to south, and the vertical axis is the positioning error (m). Further, ■ is the positioning error of the first positioning result, ▲ is the positioning error of the second positioning result, and × is the difference between the two.

As shown in FIG. 6A, when the ionosphere is in a quiet state, the positioning error of the first positioning result is smaller than the positioning error of the second positioning result at all the positioning points. On the other hand, as shown in FIG. 6B, when the ionosphere is in a disturbed state, the positioning error of the second positioning result is larger than the positioning error of the first positioning result on the south side (No. 8-15). Is getting smaller.

It is considered that the smaller the value of the positioning error, which is the result of correction based on the error correction information, the higher the accuracy of the position indicated by the corrected position information. Therefore, it is conceivable that the positioning determination unit 504 selects the positioning result having the smaller positioning error value.

According to FIG. 6, in a part of the north (Nos. 1 and 3), the positioning error of the second positioning result is slightly larger than the positioning error of the first positioning result.

Here, when the positioning result having the smaller positioning error is simply selected, for example, in the north, the first positioning result and the second positioning result are alternately selected, and the positioning information is not available. It will be continuous. On the other hand, when the difference between the two is 1 m or more (south), the positioning error of the second positioning result is continuously smaller than the positioning error of the first positioning result. In the positioning determination unit 504 according to the present embodiment, when the difference between the two becomes 1 m or more, the first positioning result and the second positioning result are obtained by switching from the first positioning result to the second positioning result. It is possible to select the positioning result having the smaller positioning error while suppressing the selection from being alternated. When the difference between the positioning error of the first positioning result and the positioning error of the second positioning result is less than 1 m, the positioning determination unit 504 returns from the second positioning result to the first positioning result.

Next, the operation procedure when the user station 500 outputs the positioning information will be described with reference to FIG. 7. In the user station 500 according to the present embodiment, the positioning determination unit 504 normally selects the first positioning result input from the first positioning unit 502 and outputs it as positioning information (S201).

The communication unit 501 receives the L1 positioning signal and the L5 positioning signal from the GPS satellites, and receives the error correction information from the master station 400 (S202).

The first positioning unit 502 performs one-frequency positioning based on the received L1 positioning signal and error correction information, and outputs the result of the one-frequency positioning as the first positioning result to the positioning determination unit 504 (S203).

The second positioning unit 503 performs dual-frequency positioning based on the received L1 positioning signal, L5 positioning signal, and error correction information, and outputs the result of the dual-frequency positioning as the second positioning result to the positioning determination unit 504. (S204).

The positioning determination unit 504 calculates the positioning error of the first positioning result from the L1 positioning signal and the error correction information, and calculates the positioning error of the second positioning result from the L1 positioning signal, the L5 positioning signal and the error correction information. (S205).

Then, the positioning determination unit 504 determines the first positioning result input from the first positioning unit 502 based on the magnitude of the difference between the calculated positioning error of the first positioning result and the positioning error of the second positioning result. And one of the second positioning results input from the second positioning unit 503 (S206). For example, when the difference between the positioning error of the first positioning result and the positioning error of the second positioning result is less than 1 m (NO in S206), the positioning determination unit 504 directly uses the first positioning result as the user station. It is output as 500 positioning information. On the other hand, in the positioning determination unit 504, the difference between the positioning error of the first positioning result and the positioning error of the second positioning result is 1 m or more, that is, the dual frequency positioning is more accurate than the one frequency positioning. If it is excellent (YES in S206), the selection destination is switched from the first positioning result to the second positioning result, and the second positioning result is output as the positioning information of the user station 500 (S207).

As described above, the user station 500 according to the present embodiment has the first positioning result or the second positioning result based on the magnitude of the difference between the positioning error of the first positioning result and the positioning error of the second positioning result. Select one of the positioning results. In this case, when the ionosphere is in a disturbed state and dual frequency positioning is more advantageous, the first positioning result and the first positioning result and the first positioning result are suppressed while suppressing the alternate selection of the first positioning result and the second positioning result. The positioning result of 2 can be optimally switched.

In the present embodiment, the navigation satellite 200 transmits a positioning signal to the monitor station 300 and the user station 500 at the respective frequencies of the L1 band and the L5 band, but the present invention is not limited to this. For example, the navigation satellite 200 may transmit positioning signals at frequencies of the L1 band and the L2 band (1227.60 MHz), respectively. Further, for example, the navigation satellite 200 may transmit a positioning signal at each frequency of the L2 band and the L5 band. Further, for example, the navigation satellite 200 may transmit a positioning signal at a frequency of the L3 (1381.05 MHz) band or the L4 (1379.913 MHz) band.

Further, in the present embodiment, the positioning determination unit 504 determines which of the 1-frequency positioning and the 2-frequency positioning is superior in positioning accuracy based on the first positioning result and the second positioning result. Not limited to. For example, the positioning determination unit 504 could not receive the L1 positioning signal and the L5 positioning signal used by the communication unit 501 when obtaining the first positioning result and the second positioning result at the point where the reception was supposed to be received. In that case, that is, when the signal is received at an unexpected point, it is determined that the ionosphere is in a disturbed state. On the other hand, when the positioning determination unit 504 receives the L1 positioning signal and the L5 positioning signal used when the communication unit 501 obtains the first positioning result and the second positioning result at a point where reception is expected, It is determined that the ionosphere is in a static state.

Further, in the description of the above operation procedure, the positioning method initially set for the user station 500 is 1-frequency positioning, but the positioning method initially set for the user station 500 is 2-frequency positioning. May be good. Further, for example, the positioning method may not be initially set in the user station 500.

In this embodiment, the positioning error of the first positioning result and the positioning error of the second positioning result are calculated based on one error correction information, respectively. However, the first correction information in the L1 band, which is the frequency band of the L1 positioning signal, and the second correction information in the L5 band, which is the frequency band of the L5 positioning signal, may be prepared respectively. Then, the first positioning result may be configured to be calculated based on the L1 positioning signal and the first correction information. Specifically, for example, a first correction indicating a position in which the first position information is generated based on the L1 positioning signal and the position indicated by the first position information is corrected based on the first correction information. Location information is generated. Then, the positioning error of the first positioning result is calculated by calculating the distance between the position indicated by the first position information and the position indicated by the first corrected position information.

Further, the second positioning result may be configured to be calculated based on the L1 positioning signal, the L5 positioning signal, and the second correction information. Specifically, for example, a position in which the second position information is generated based on the L1 positioning signal and the L5 positioning signal and the position indicated by the second position information is corrected based on the second correction information is obtained. The second corrected position information shown is generated. Then, the positioning error of the second positioning result is calculated by calculating the distance between the position indicated by the second position information and the position indicated by the second corrected position information.

Although each embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiments, and further modifications, substitutions, and modifications are made without departing from the basic technical idea of the present invention. Adjustments can be made. In addition, each embodiment may be combined as appropriate.

The disclosures of the above patent documents and non-patent documents shall be incorporated into this document by citation. Within the framework of all disclosures (including claims) of the present invention, the embodiments can be changed and adjusted based on the basic technical idea thereof. In addition, various combinations or selections of various disclosure elements are possible within the scope of the claims of the present invention. That is, it goes without saying that the present invention includes all disclosure including claims, and various modifications and modifications that can be made by those skilled in the art in accordance with the technical idea.

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 configuration and details of the present invention within the scope of the present invention.

This application claims priority on the basis of Japanese Application Japanese Patent Application No. 2015-143760 filed on 21 July 2015 and incorporates all of its disclosures herein.

10 Positioning device 11 First positioning means 12 Second positioning means 13 Determining means 100 Positioning system 200 Navigation satellite 300 Monitor station 400 Master station 401 Communication unit 402 Ionospheric delay calculation unit 403 Grid information generation unit 404 Orbit correction information generation unit 405 Clock correction information generation unit 500 User station 501 Communication unit 502 First positioning unit 503 Second positioning unit 504 Positioning determination unit

Claims (6)

A first positioning means that outputs a first positioning result based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal, and
A second positioning means that outputs a second positioning result based on the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal.
Based on the comparison result between the output first positioning result and the output second positioning result, either the first positioning result or the second positioning result is selected and output as positioning information. Determining means and
Equipped with a,
The determination means is
The first measurement error is calculated from the first positioning signal and the first correction information, and the second measurement error is calculated from the second positioning signal and the second correction information.
When the difference between the calculated first measurement error and the second measurement error is smaller than a predetermined threshold value, the first positioning result is selected.
When the difference between the calculated first measurement error and the second measurement error is equal to or greater than a predetermined threshold value, the second positioning result is selected.
A positioning device characterized by this. The first frequency is the L1 band (1575.42 MHz).
The second frequency is the L5 band (1176.45 MHz).
The positioning device according to claim 1 . The first positioning signal and the second positioning signal are positioning signals transmitted from GPS satellites.
The positioning device according to claim 1 or 2 . The predetermined threshold is 1 m.
The positioning device according to any one of claims 1 to 3 . The positioning device according to claim 1 or 2 , further comprising a communication means for receiving the first correction information and the second correction information.
A control device that transmits the first correction information and the second correction information to the positioning device, and
Positioning system equipped with. The first positioning result is output based on the first positioning signal of the first frequency and the first correction information regarding the first positioning signal.
The second positioning result is output based on the first positioning signal, the second positioning signal of the second frequency, and the second correction information regarding the second positioning signal.
Output as positioning information by selecting one of the output first positioning result and the outputted second positioning result and compared on the basis of the results first positioning result or the second positioning result of ,
In the process of selecting one of the first positioning result and the second positioning result and outputting it as positioning information.
The first measurement error is calculated from the first positioning signal and the first correction information, and the second measurement error is calculated from the second positioning signal and the second correction information.
When the difference between the calculated first measurement error and the second measurement error is smaller than a predetermined threshold value, the first positioning result is selected.
When the difference between the calculated first measurement error and the second measurement error is equal to or greater than a predetermined threshold value, the second positioning result is selected.
Positioning method.

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