JP2019095234A - Satellite positioning device - Google Patents

Abstract

To provide a satellite positioning device that can perform a highly precise positioning.SOLUTION: The satellite positioning device equipped in a vehicle includes: a signal receiving unit 103 for receiving an electric signal from a satellite; a positioning unit 119 for acquiring the current position of the vehicle based on an electric signal received by the signal receiving unit 103; and a control unit 123 for selecting one of a plurality of methods for positioning and instructing the positioning unit 119 to perform positioning by the selected method. The plurality of methods use satellites different at least partially.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a satellite positioning device.

  Conventionally, various services have been put into practical use by calculating current position information using a Global Navigation Satellite System (GNSS). GNSS is a general term for satellite positioning systems such as GPS (Global Positioning System), GALILEO, GLONASS, Quasi-Zenith Satellite System (QZSS), and the like.

  In single-frequency satellite positioning using GPS satellites and the like, it is said that the error from the accurate position will be about 10 m. For example, in a car navigation system mounted on a car or the like, due to this error, the current position may not be displayed on the road on the display although the vehicle is actually traveling on the road. Therefore, map matching processing is known as a technique for correcting the display of the current position (for example, Patent Document 1). The map matching process is a technique of correcting the current position on the road by matching the locus of the current position determined one by one with the road shape. By performing the processing, it is possible to accurately display the current position on the display.

JP, 2008-097413, A

  However, according to the above map matching process, if the road shape similar to the traveling locus of the vehicle is near the current position, the current position of the vehicle resembles the traveling locus even if it does not completely match the traveling locus. It may correct on the road which has shape. Therefore, for example, when traveling on a road traveling in parallel in the same direction, the current position may be displayed on a road traveling in parallel, which is different from the actual position, by the correction. As described above, since accurate display of the current position can not be surely performed even by the map matching process, a technique capable of measuring the current position with high accuracy is required.

  The present invention provides a satellite positioning device capable of highly accurate positioning.

The present invention
A satellite positioning device mounted on a vehicle,
A signal receiving unit for receiving radio signals from satellites;
A positioning unit for acquiring the current position of the vehicle based on the radio wave signal received by the signal reception unit;
A control unit which selects one of a plurality of positioning methods and instructs the positioning unit to perform positioning using the selected positioning method;
The plurality of positioning methods differ in at least part of the satellites used.

  According to the present invention, since the positioning method is selected by selecting a more suitable positioning method among a plurality of positioning methods, stable and accurate positioning can be performed compared to the case where positioning is performed using only a single positioning method. Is possible.

It is the schematic which shows the example of vehicle interior installation of the radar detector which mounts the satellite positioning apparatus of one Embodiment of this invention. It is the schematic which shows the other vehicle interior installation example of the radar detector containing the satellite positioning apparatus of one Embodiment of this invention. It is a block diagram which shows the internal structure of the radar detector shown in FIG.1 and FIG.2.

  Hereinafter, a radar detector equipped with a satellite positioning device according to an embodiment of the present invention will be described with reference to the drawings. The radar detector is provided with a function to warn the user and follow the speed in order to comply with the speed limit of a vehicle such as a car.

  FIG. 1 is a schematic view showing a radar detector provided in a vehicle compartment. As shown in FIG. 1, the radar detector 100 of the present embodiment is held by a bracket fixed to the upper surface of a dashboard DB of a vehicle by a double-sided tape or the like. As shown in FIG. 2, the radar detector 100 may be a mirror type which is fixed by being sandwiched between upper and lower rearview mirrors RM provided in the vehicle. 1 and 2 are viewed in the direction of the reference numerals, and the front, rear, left, right, up and down according to the direction seen from the driver, Fr in the front of the vehicle, Rr in the rear, L in the left, R in the right in the drawing , U above, D below.

  FIG. 3 is a block diagram showing an internal configuration of the radar detector 100 shown in FIG. 1 and FIG. As shown in FIG. 3, the radar detector 100 includes a radar wave detection unit 101, a signal reception unit 103, an acceleration sensor 105, a gyro sensor 107, an air pressure sensor 109, a data memory 111, and a display 113. A speaker 115, a primary storage memory 117, a positioning unit 119, a map storage unit 121, and a control unit 123 are included. The radar detector 100 is supplied with power via a power cable (not shown) connected to a DC power supply system of the vehicle.

  Hereinafter, each component which the radar detector 100 has is demonstrated.

  The radar wave detection unit 101 detects a radar wave emitted from a radar-type speed measuring device, an automatic speed control device, or the like. The radar wave detection unit 101 also detects the detected radar wave and sends a detection signal of the radar wave to the control unit 123.

  The signal receiving unit 103 receives radio signals from satellites such as GPS satellites, geostationary satellites and quasi-zenith orbit satellites. The radio signal transmitted from the satellites includes signals for positioning reinforcement as well as signals for positioning transmitted by each satellite. The radio wave signal received by the signal receiving unit 103 is sent to the positioning unit 119 and the control unit 123.

  The acceleration sensor 105 detects the traveling acceleration of a vehicle equipped with the radar detector 100. A signal indicating the acceleration detected by the acceleration sensor 105 is sent to the control unit 123. The gyro sensor 107 detects the rotational angular velocity of the vehicle on which the radar detector 100 is mounted. A signal indicating the angular velocity detected by the gyro sensor 107 is sent to the control unit 123. The barometric pressure sensor 109 detects the barometric pressure around the radar detector 100. A signal indicating the air pressure detected by the air pressure sensor 109 is sent to the control unit 123.

  The data memory 111 stores road traffic information at positions corresponding to the latitudes and longitudes of all over Japan, and speed limit information of each road of expressways and general roads. In addition, with "road traffic information", there is a fixed type radar type, speed measuring machine (measurement camera), speed warning board, a loop coil equipped with a camera and a loop sensor as a measurement sensor as a speed violation control machine (Obis). Measuring the time taken for a vehicle to pass a certain section using a NH type sensor, "NH system", stealth type, phototube type or infrared type measurement sensor to determine the traveling speed, patrol car for mobile type Information that indicates the signal and installation position of a radar-type enforcement device etc. loaded on the roof of the

  The display 113 displays a setting screen, a warning screen, a standby screen and the like of the radar detector 100. The speaker 115 outputs, for example, a sound such as an operation sound or a warning of a switch not shown. The primary storage memory 117 is a cache memory for temporarily storing data such as video to be displayed on the display 113.

  The positioning unit 119 acquires the current position of the vehicle equipped with the radar detector 100 based on the radio wave signal received by the signal receiving unit 103. The positioning unit 119 performs positioning by the positioning method instructed from the control unit 123. Information indicating the current position acquired by the positioning unit 119 is sent to the control unit 123. The map storage unit 121 stores information of road maps throughout Japan.

  The control unit 123 issues a warning using the display 113 and / or the speaker 115 in accordance with the detection signal from the radar wave detection unit 101. That is, when the radar wave detection unit 101 detects a radar wave, the control unit 123 controls the display unit 113 to display a warning screen indicating that enforcement by the radar wave is being performed, and controls the speaker 115 to output a warning sound. . In addition, the control unit 123 calculates the traveling speed of the vehicle equipped with the radar detector 100 based on the time change of the radio signal from the signal receiving unit 103 or the signal from the acceleration sensor 105. In addition, the control unit 123 acquires road traffic information or speed limit information related to the current position from the data memory 111, and issues a warning according to the acquired information using the display 113 and / or the speaker 115.

  Furthermore, the control unit 123 instructs the positioning unit 119 to perform positioning by a positioning method suitable for the external environment or the like of the vehicle equipped with the radar detector 100. There are two positioning methods that can be selected by the control unit 123. One is to perform positioning using positioning signals from GPS satellites and perform error correction using error correction information distributed from geostationary satellites. The measurement method using a system called “Satellite-Based Augmentation System”, and the other is “SLAS (Sub) that performs positioning using positioning signals from GPS satellites and positioning signals from Quasi-Zenith Satellites or reinforcement signals. measurement method using a system called “meter Level Augmentation Service”. That is, at least a part of the satellites to be used is different between the measurement method using SBAS and the measurement method using SLAS. The Japanese quasi-zenith satellite system “MICHIBIKI” is used for positioning with SLAS in Japan.

  The control unit 123 measures the measurement method using SBAS (hereinafter referred to simply as "SBAS") and the measurement method using SLAS (hereinafter referred to simply as "SLAS" according to the external environment etc. of the vehicle equipped with the radar detector 100). Select one of the appropriate measurement methods and switch automatically. The error correction information distributed from the geostationary satellite by SBAS is distributed as information for each error factor, and the error information related to the ionospheric delay, which is one of the error factors, can also be applied to satellites other than GPS satellites. Therefore, as the number of satellites that can use the error correction information, SBAS is larger than SLAS. On the other hand, since SLAS can receive positioning signals from not only GPS satellites but also Quasi-Zenith satellites in locations where the view upward and diagonally upward is good, stable high-precision positioning is possible. However, where there are many obstacles, such as mountain areas and valleys of buildings, the positioning signal must be accurate because of signal shielding and multipath where radio signals from satellites are reflected by trees and buildings and delayed. The number of satellites that can be received is reduced. In this case, SBAS can perform higher precision positioning than SLAS.

  The control unit 123 automatically selects a positioning method that is more suitable for the position and environment of the vehicle equipped with the radar detector 100 based on the features of the SBAS and SLAS. Hereinafter, selection conditions of the positioning method by the control unit 123 will be described.

(First condition)
The control unit 123 selects an SLAS when the distance between a reference station that obtains an error of the measurement distance for each GPS satellite and distributes the error information via the quasi-zenith satellite and the current position is, for example, 0 to 150 km. If the vehicle equipped with the radar detector 100 is located within a range of 0 to 150 km from the reference station, the error information distributed from the Quasi-Zenith Satellite can be effectively used as positioning reinforcement information. Positioning is possible. Although the location information of the reference station may be stored by the map storage unit 121, it is more preferable to use the latest reference station information distributed from the quasi-zenith satellite.

(Second condition)
The control unit 123 selects the SLAS when the number of satellites for which the signal receiving unit 103 receives a radio wave signal from a satellite transmitting a positioning signal is equal to or more than a predetermined value. If the number of satellites from which the signal reception unit 103 receives a radio wave signal is equal to or more than a predetermined value, it is considered that the view from the vehicle equipped with the radar detector 100 is wide and favorable. Therefore, the positioning unit 119 can perform high-accuracy positioning by SLAS without the influence of signal shielding and multipath.

(Third condition)
The control unit 123 selects the SLAS when the accuracy reduction rate (DOP: Dilution of Precision) indicating the degree to which the positioning accuracy decreases due to the arrangement of the satellites with respect to the radar detector 100 is equal to or less than a predetermined value. If DOP becomes smaller, the positioning accuracy becomes higher, so if DOP is less than a predetermined value, high-accuracy measurement by SLAS is possible.

(The 4th condition)
The control unit 123 selects one of SBAS and SLAS depending on whether the current position of the vehicle equipped with the radar detector 100 acquired by the positioning unit 119 is on a road of a predetermined form or in a predetermined area. Do. For example, if the current position of the vehicle is, for example, on a freeway, there is a high possibility that the upward and diagonally upward visibility is good. Therefore, if SLAS is selected, more accurate positioning than SBAS is possible. In addition, if the current position of the vehicle is, for example, in an area where a high-rise building stands, the view to the upper side is bad, and there is a high possibility that the number of satellites that can receive positioning signals is small. In this case, if SBAS is selected, the number of satellites that can use the error correction information distributed from the geostationary satellite can be increased, so SBAS can be positioned with higher accuracy than SLAS.

  Also, instead of the first to fourth conditions, SBAS or SLAS may be selected by the satellite first captured when the radar detector 100 is activated. That is, if the satellite first captured is a quasi-zenith satellite, select SLAS, and if it is an SBAS satellite, select SBAS.

  The present invention is not limited to the above embodiment, and appropriate modifications, improvements, and the like can be made. For example, in the present specification, the radar detector 100 is described as an example of an onboard information terminal equipped with the satellite positioning device of the present invention, but the onboard information terminal may be a drive recorder or a car navigation system, for example. .

  As described above, the following matters are disclosed in the present specification.

(1) A satellite positioning device mounted on a vehicle,
A signal receiving unit for receiving radio signals from satellites;
A positioning unit for acquiring the current position of the vehicle based on the radio wave signal received by the signal reception unit;
A control unit which selects one of a plurality of positioning methods and instructs the positioning unit to perform positioning using the selected positioning method;
The satellite positioning device, wherein the plurality of positioning methods are different in at least a part of satellites used.

  According to (1), since the positioning is performed by selecting the positioning method that is more suitable than the plurality of positioning methods, stable and high accuracy can be achieved compared to the case where positioning is performed using only a single positioning method. Positioning is possible.

(2) The satellite positioning device according to (1), wherein
The plurality of positioning methods include a first positioning method for performing positioning based on each radio wave signal from the GPS satellites and geostationary satellites received by the signal receiving unit, and a GPS satellite and quasi-zenith satellites received by the signal receiving units. A satellite positioning device, comprising: a second positioning method for positioning based on each radio signal.

  According to (2), the satellite positioning device capable of improving the positioning accuracy between the first positioning method using the radio signal from the geostationary satellite for positioning and the second positioning method using the radio signal from the quasi-zenith satellite for positioning These environments are different from each other, so high-accuracy positioning can be performed by performing positioning according to either the first positioning method or the second positioning method, whichever is more appropriate depending on the position where the satellite positioning device is placed or the environment. .

(3) The satellite positioning device according to (2),
The control unit
The second positioning method is selected when the distance between the satellite positioning device and the reference station that determines the error of the measured distance for each GPS satellite and distributes the error information via the quasi-zenith satellite is less than or equal to a predetermined value A satellite positioning device.

  According to (3), when the distance between the reference station and the satellite positioning device is within the predetermined value, if the positioning unit performs the positioning by the second positioning method, the satellite positioning device receives the error information distributed by the quasi-zenith satellite Since it can be used effectively as positioning reinforcement information, highly accurate positioning is possible.

(4) The satellite positioning device according to (2),
The control unit
The satellite positioning device, which selects the second positioning method when the number of satellites from which the signal reception unit receives a radio signal is equal to or more than a predetermined value.

  According to (4), it is considered that the visibility from the satellite positioning device is wide and good when the number of satellites from which the signal reception unit receives the radio signal is a predetermined value or more. 2 Positioning can be performed by the positioning method.

(5) The satellite positioning device according to (2), wherein
The control unit
The satellite positioning device, which selects the second positioning method when the accuracy decrease rate indicating the degree of decrease in the positioning accuracy is equal to or less than a predetermined value.

  The accuracy reduction rate indicates the degree to which the positioning accuracy is lowered due to the arrangement of the satellites from which the signal reception unit receives the radio signal with respect to the satellite positioning device. As the accuracy reduction rate decreases, the positioning accuracy increases. Therefore, as described in (5), by performing the positioning using the second positioning method when the accuracy decrease rate is less than or equal to the predetermined value, the second positioning is performed in a high positioning accuracy state. It can measure by the method.

(6) The satellite positioning device according to (2),
The control unit
A satellite positioning device, which selects the first positioning method or the second positioning method according to whether the current position of the vehicle measured by the positioning unit is on a road of a predetermined form or within a predetermined area.

  According to (6), if the current position of the vehicle is, for example, on a freeway, there is a high possibility that the view to the upper side and the upper side is good. Therefore, high accuracy positioning can be performed by selecting the second positioning method. Is possible.

(7) The satellite positioning device according to any one of (2) to (6), wherein
The control unit
A satellite positioning device, which selects the first positioning method when the satellite positioning device is activated and the positioning unit performs positioning for the first time.

  The error correction information distributed from the geostationary satellite used in the first positioning method is information for each error factor, and “ionosphere delay error information” which is one of the error factors is also applied to satellites other than GPS satellites. As it is possible, the first positioning method has more satellites available. According to (7), since the positioning that is performed first when the satellite positioning device is activated is performed by the first positioning method that uses a large number of satellites, positioning can be performed quickly under good reception conditions.

100 radar detector 101 radar wave detection unit 103 signal reception unit 105 acceleration sensor 107 gyro sensor 109 atmospheric pressure sensor 111 data memory 113 display 115 speaker 117 primary storage memory 119 positioning unit 121 map storage unit 123 control unit

Claims (7)

A satellite positioning device mounted on a vehicle,
A signal receiving unit for receiving radio signals from satellites;
A positioning unit for acquiring the current position of the vehicle based on the radio wave signal received by the signal reception unit;
A control unit which selects one of a plurality of positioning methods and instructs the positioning unit to perform positioning using the selected positioning method;
The satellite positioning device, wherein the plurality of positioning methods are different in at least a part of satellites used. The satellite positioning device according to claim 1, wherein
The plurality of positioning methods include a first positioning method for performing positioning based on each radio wave signal from the GPS satellites and geostationary satellites received by the signal receiving unit, and a GPS satellite and quasi-zenith satellites received by the signal receiving units. A satellite positioning device, comprising: a second positioning method for positioning based on each radio signal. The satellite positioning device according to claim 2, wherein
The control unit
The second positioning method is selected when the distance between the satellite positioning device and the reference station that determines the error of the measured distance for each GPS satellite and distributes the error information via the quasi-zenith satellite is less than or equal to a predetermined value A satellite positioning device. The satellite positioning device according to claim 2, wherein
The control unit
The satellite positioning device, which selects the second positioning method when the number of satellites from which the signal reception unit receives a radio signal is equal to or more than a predetermined value. The satellite positioning device according to claim 2, wherein
The control unit
The satellite positioning device, which selects the second positioning method when the accuracy decrease rate indicating the degree of decrease in the positioning accuracy is equal to or less than a predetermined value. The satellite positioning device according to claim 2, wherein
The control unit
A satellite positioning device, which selects the first positioning method or the second positioning method according to whether the current position of the vehicle measured by the positioning unit is on a road of a predetermined form or within a predetermined area. The satellite positioning device according to any one of claims 2 to 6, wherein
The control unit
A satellite positioning device, which selects the first positioning method when the satellite positioning device is activated and the positioning unit performs positioning for the first time.

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