KR101707860B1 - Method for correcting error of the location data of satallite data - Google Patents

Method for correcting error of the location data of satallite data Download PDF

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Publication number
KR101707860B1
KR101707860B1 KR1020150127467A KR20150127467A KR101707860B1 KR 101707860 B1 KR101707860 B1 KR 101707860B1 KR 1020150127467 A KR1020150127467 A KR 1020150127467A KR 20150127467 A KR20150127467 A KR 20150127467A KR 101707860 B1 KR101707860 B1 KR 101707860B1
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KR
South Korea
Prior art keywords
data
ship
detection data
detected
position information
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KR1020150127467A
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Korean (ko)
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양찬수
정재훈
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한국해양과학기술원
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/03—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
    • G01S19/07—Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/14—Receivers specially adapted for specific applications
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/20—Integrity monitoring, fault detection or fault isolation of space segment
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/31—Acquisition or tracking of other signals for positioning

Abstract

The present invention receives location information from another apparatus such as AIS having more precise position information than satellite data, detects an area detected by the satellite data in the AIS apparatus, and uses the more accurate position information of the AIS to detect the satellite data And to a method for correcting a position coordinate.
A method for correcting a position coordinate error of satellite data according to the present invention includes: a first data receiving step of receiving first ship detection data based on satellite data for objects to be detected with respect to a first selected region of the sea; A second data reception step of receiving second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base with respect to the second selection region which is a partial region within the first selection region; A reference object selection step of selecting reference detection objects detected in both the first ship detection data and the second ship detection data; A reference object position correction step of correcting the position information of the reference detection objects detected in the first ship detection data based on the precise position information of the reference detection objects detected in the second ship detection data; And a total object which corrects the position information of the objects to be detected other than the reference target detection target squares in the first ship detection data by using a correction value obtained by correcting the position information of the reference detection target objects in the first ship detection data And a position correcting step.

Description

Field of the Invention < RTI ID = 0.0 > [0001] < / RTI &

The present invention relates to a method for correcting a geometrical error of remote sensing information obtained from a sensor mounted on a satellite or an aircraft. The method is based on a payload geometry modeling method, The present invention relates to a method of using a stationary or mobile float at sea. More particularly, the present invention relates to an apparatus and method for receiving positional information from another apparatus such as a moving object having more precise positional information than satellite data and using more accurate positional information in a mobile apparatus located in an area detected by the satellite data, And a method for correcting the error.

Recently, the use of remote sensing data and remote sensing technology for the marine area is increasing, and target detection technology such as a ship using satellite data is actively being actively carried out. In this case, precise location information for such satellite-based targets is required.

In the case of marine detection using satellite data, a method of calculating the coordinates of all pixels using coordinates of some points present in the satellite meta information is used. In this case, although the position information is given to the satellite-based detection target, As well as position errors ranging from tens to hundreds of meters.

Especially, in case of land, it is possible to correct the position coordinates of the satellite data by using fixed coordinates of the reference points by setting the fixed reference points. However, in case of satellite data for the marine area, This makes the geometric correction more difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a position correction method of satellite data, which can precisely obtain position information on a target to be detected, / RTI >

A method for correcting a positional coordinate error of satellite data according to an embodiment of the present invention includes: a first data receiving step of receiving first ship detection data based on a satellite data with respect to objects to be detected with respect to a first selected region of the sea; A second data reception step of receiving second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base with respect to the second selection region which is a partial region within the first selection region; A reference object selection step of selecting reference detection objects detected in both the first ship detection data and the second ship detection data; A reference object position correction step of correcting the position information of the reference detection objects detected in the first ship detection data based on the precise position information of the reference detection objects detected in the second ship detection data; And a total object which corrects the position information of the objects to be detected other than the reference target detection target squares in the first ship detection data by using a correction value obtained by correcting the position information of the reference detection target objects in the first ship detection data And a position correcting step.

In a preferred embodiment, the reference object to be detected is a fixed float floating in the sea, the second vessel detection data is the positional information of the fixed float, and the fixed float is the floating buoys, lighthouses, Barges or observers.

In a preferred embodiment, the reference object to be detected is a floating float floating in the sea, the second vessel detection data is position information of the floating floats, and the floating floats are floating vessels.

In a preferred embodiment, the second vessel detection data is position information obtained from the AIS data obtained from the vessels.

In a preferred embodiment, the second vessel detection data is radar scattering data obtained from the vessels.

In a preferred embodiment, the second vessel detection data is position information obtained from the AIS data obtained from the vessels and linear information of each vessel obtained from the AIS data, and in the reference object position correction step, Correcting positional information and linear information of the reference detection target objects detected in the first ship detection data based on precise position information and linear information of the reference detection target objects detected in the data, Using the correction values corrected for the position information and the linear information of the reference detection target objects in the first ship detection data, corrects the position information of the detection target objects other than the reference detection target squares in the first ship detection data do.

According to the present invention, positional information is received from various stationary devices or mobile devices floating in the sea as well as satellite data, and used for correcting the position coordinates of the satellite data, thereby providing more accurate position information It is possible to acquire the data having the data.

Further, there is an advantage that more accurate position correction is possible by correcting the position information of the satellite data by using the position information obtained from the AIS as well as the linear information of the ship obtained from the AIS.

FIG. 1 is a flowchart of a position coordinate error correction method of satellite data according to an embodiment of the present invention,
2A is a diagram showing a detection state of targets on the pre-correction satellite data,
FIG. 2B is a view showing AIS information acquired at the same time as the time at which the satellite data is acquired,
FIG. 2C is a view showing objects to be detected in an area where both satellite data and AIS information are acquired,
FIG. 3A is a diagram showing the correction of the position of the satellite data with respect to the target using the AIS information of FIG. 2B,
FIG. 3B is a diagram showing a detection state of targets after correcting the position coordinates of the satellite data using the AIS information, and FIG.
4 is a diagram for explaining a process of receiving position information and linear information of a ship from an AIS and correcting the position information of the satellite data.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to or limited by the embodiments. Like reference symbols in the drawings denote like elements.

[First Embodiment]

FIG. 1 is a flowchart of a position coordinate error correction method of satellite data according to an embodiment of the present invention.

Referring to FIG. 1, a method for correcting a position coordinate error of satellite data according to an embodiment of the present invention includes: a first step of receiving first ship detection data based on satellite data, And a second selection area that is a part of the first selection area and receives second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base, A reference object selecting step (S300) of selecting reference object to be detected detected in both the first ship detection data and the second ship detection data (S200), the reference object detection step A reference object position correcting step (S400) of correcting position information of the reference target objects detected in the first ship detection data based on accurate position information of the target objects, Detecting a position of the object to be detected from the first vessel detection data by using a correction value obtained by correcting the position information of the reference object to be detected in the first vessel detection data; And a correction step S500.

First, the first ship detection data based on the satellite data is received for the objects to be detected with respect to the first selection region 100, which is a predetermined region of the sea (S100). In the first data receiving step, detection data is acquired using a satellite for a detection target object such as a ship located in a specific area of the sea, and is called first ship detection data.

Next, the second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base is received for the second selection region 200, which is a partial region within the first selection region (S200) The reference detection objects detected in both the first ship detection data and the second ship detection data are selected (S300).

Wherein the second vessel detection data is detection data for a partial area within the entire area from which the first vessel detection data is obtained and the second vessel detection data is from a fixed or mobile float floating in the sea, .

These fixed or mobile floats serve as a reference point for the correction of the position of the satellite data on the marine area, such as using specific fixed reference points on land for the correction of the position of the satellite data on land.

Accordingly, the second ship detection data may be positional information of the fixed or mobile floats, and the fixed floats may be one of floating buoys, lighthouses, barges or observers, Can be floating vessels at sea. Therefore, the second ship detection data is position information received from the AIS or the radar device mounted on the ship.

In the embodiment of the present invention, among the objects detected in the first ship detection data, the object detected both in the second ship detection data, i.e., both the first ship detection data and the second ship detection data, Referred to as a reference detection target object.

Wherein the reference object to be detected is a floating or mobile float floating above the sea and the fixed or mobile floats are the device for obtaining the second vessel detection data and they are the reference to be selected from the second vessel detection data And becomes the object to be detected.

In the embodiment of the present invention, the second ship detection data is acquired from the AIS information acquired from a ship having a floating suspension.

2B is a view showing AIS information acquired at the same time as the time at which the satellite data is acquired, and FIG. 2C is a view showing the AIS information acquired at both the time when the satellite data and the AIS information are both FIG. 5 is a view showing objects to be detected in the obtained area. FIG.

The area indicated by a dotted line in FIG. 2A is a region in which data is acquired from the floating submerged fluid, that is, the AIS of the ship, into the second selection region. In FIG. 2A, in this area, the ships equipped with AIS denoted by triangles, that is, the ships 110 in which the second ship detection data is being acquired, and the other detected objects 120 (indicated by circles) ). FIG. 2B shows the vessels represented by the acquired AIS information for the second selection area 200. FIG. The ships are ships equipped with an AIS, and they are objects 210 to be detected having their own accurate position information.

2A and 2B show the same objects as the objects 110 to be detected in FIG. 2A and the objects 210 to be detected in FIG. 2B, respectively. And the reference object to be detected are all detected in the second ship detection data.

In FIG. 2C, the detection objects 110 and 120 identified by the satellite data and the detection objects 210 identified from the AIS are shown together in the second selection area. Referring to FIG. 2C, it can be seen that the detection objects 110 identified by the satellite data and the detection object 210 identified by the AIS are located at different positions. Since these are the same objects, if the location information of two pieces of data is correct, these objects should be superimposed exactly one on top of each other. However, if the positional information of one data is different or if the positional information of the two data are different, they are not overlapped with each other as shown in FIG.

Next, the position information of the reference target objects detected in the first ship detection data is corrected based on the accurate position information of the reference target objects detected in the second ship detection data (S400).

FIG. 3A is a diagram illustrating a correction of a position of the target of the satellite data using the AIS information of FIG. 2B. FIG. 3B is a diagram illustrating a target detection state after correcting the position coordinates of the satellite data by using the AIS information. Showing the drawings,

3A and 3B, in order to correct the position of the reference object, first, the position information of the reference object 210 detected in the second ship detection data and the position information of the reference object 210 detected in the first ship detection data The location information of the reference detection target objects 110 is compared with each other to check whether there is a difference between the two location information. Since the position information of the reference object to be detected detected in the second ship detection data is position information having higher accuracy than the position information of the reference object to be detected detected in the first ship detection data, Information.

When there is a difference between two pieces of positional information, precision position information of the reference detection target objects detected in the second ship detection data is used as a reference, and the position of the reference detection target objects detected in the first ship detection data Information is corrected to the precise position information. That is, the position information is corrected by a difference value appearing between two position information so that the reference detection target objects detected in the first ship detection data are positioned at the positions of the reference detection target objects detected in the second ship detection data .

In this case, the difference value may be the same for all the reference object to be detected, but the difference value between the reference object to be detected and the corresponding reference object to be detected may be different from each other. In this case, it is also possible to correct the position information of all the reference detection objects using the average difference value after calculating the average value of all difference values, or to correct the difference value separately for each reference detection object Do.

Next, using the correction values obtained by correcting the positional information of the reference target objects 110 in the first ship detection data, the detection target objects 120 (S500).

And corrects the position information of the objects to be detected other than the reference detection target gyros in the first ship detection data by directly using the difference value used for the position correction in the reference object position correction step.

If the positions of the objects to be detected are corrected using the average difference value, the positional correction is performed with respect to all the objects to be detected with the same difference value. If the positions of the objects to be detected are corrected, If so, the average difference value is calculated for the remaining objects to be detected, and the same position correction is performed using the average difference value.

[Second Embodiment]

Hereinafter, a method for correcting a position coordinate error of satellite data according to a second embodiment of the present invention will be described.

In the position coordinate error correction method of the satellite data according to the second embodiment of the present invention, the second ship detection data includes not only position information obtained from the AIS data acquired from the ships, but also linear information of each ship obtained from the AIS data .

Therefore, the method of correcting the position coordinate error of the satellite data according to the second embodiment of the present invention is similar to that of the first embodiment, Receiving second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base with respect to the second selection region which is a partial region within the first selection region A second data receiving step, a reference object selecting step of selecting all of the reference detection objects detected in the first vessel detection data and the second vessel detection data, A reference object position correction unit for correcting position information of the reference detection objects detected in the first ship detection data on the basis of the accurate position information, And a correction value obtained by correcting the position information of the reference object to be detected in the first ship detection data to correct the position information of the objects to be detected other than the reference object to be detected in the first ship detection data And an object position correcting step.

In this case, since the second vessel detection data is position information obtained from the AIS data obtained from the vessels and linear information of each vessel obtained from the AIS data, in the reference object position correction step, Correcting the position information and the linear information of the reference detection target objects detected in the first ship detection data on the basis of the precise position information and the linear information of the reference detection target objects, And corrects the position information of the objects to be detected other than the reference target detection gaps in the first ship detection data by using the correction values obtained by correcting the position information and the linear information of the reference detection target objects in the ship detection data.

The linear information of the ship obtained from the AIS is information on the shape and size of the ship. Therefore, when acquiring the linear information of the ship together with the position information from the AIS together with the accurate position information obtained from the AIS information having higher accuracy than the data obtained from the satellite, And corrects the position information of the satellite data by using the linear information of the ship. Direction information of the ship's athlete or stern obtained from the AIS can be corrected to each other by comparing information such as the bow or stern of the ship in the information obtained from the satellite.

4 is a diagram for explaining a process of receiving position information and linear information of a ship from an AIS and correcting the position information of the satellite data. In FIG. 4, the position and linear information of the ship 410 obtained from the AIS and the position and linear information of the ship 310 obtained from the satellite are displayed. Referring to FIG. 4, it is possible to find the direction of the ship (indicated by d31, d32, d33, d41, d42, d43) using the linear information for each ship, (D41, d42, d43) of each ship obtained from the satellite are compared with the navigation directions (d31, d32, d33) of the respective ships obtained from the satellite. Usually, since the navigation direction information of the ship obtained from the AIS is more accurate than the data obtained from the satellite, the navigation direction of the ship obtained from the AIS is corrected by correcting the navigation direction of the ship obtained from the satellite.

 In this way, when using not only the position information obtained from the AIS but also the ship's linear information, it is possible to correct the position information more accurately than the position information of the object to be detected is corrected using only the position information.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention.

Claims (6)

A first data receiving step of receiving first ship detection data on a satellite data basis for objects to be detected with respect to a first selected area of the sea;
A second data reception step of receiving second ship detection data at the same time as the acquisition time of the first ship detection data of the satellite data base with respect to the second selection region which is a partial region within the first selection region;
A reference object selection step of selecting reference detection objects detected in both the first ship detection data and the second ship detection data;
A reference object position correction step of correcting the position information of the reference detection objects detected in the first ship detection data based on the precise position information of the reference detection objects detected in the second ship detection data; And
A total object which corrects the position information of the remaining detection objects other than the reference detection objects in the first ship detection data by using a correction value obtained by correcting the position information of the reference detection objects in the first ship detection data; And a position correction step,
Wherein the reference object to be detected is a movable float floating in the sea,
Wherein the second vessel detection data is positional information of the movable floats,
The movable floats are marine vessels,
The second ship detection data is position information obtained from the AIS data acquired from the ships,
The second ship detection data is position information obtained from the AIS data obtained from the ships and linear information of each ship obtained from the AIS data,
The positional information of the reference object to be detected detected in the first ship detection data on the basis of the precise position information and the linear information of the reference object to be detected detected in the second ship detection data, Correcting the linear information,
Wherein the correcting of the entire object position is performed by using correction values corrected for the position information and the linear information of the reference detection target objects in the first ship detection data, And correcting the positional information of the objects. delete delete delete delete delete
KR1020150127467A 2015-09-09 2015-09-09 Method for correcting error of the location data of satallite data KR101707860B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020091159A1 (en) * 2018-11-02 2020-05-07 한국항공우주연구원 Method and device for correcting image sensor misalignment by using ship identification information

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003269957A (en) * 2002-03-18 2003-09-25 Mitsubishi Space Software Kk Position correction device and position correction method for satellite image
JP2003288698A (en) * 2002-03-27 2003-10-10 Mitsui Eng & Shipbuild Co Ltd Nearby vessel information integrating method and device
JP2015036832A (en) * 2013-08-12 2015-02-23 株式会社日立ソリューションズ Data complementary device, data complementary method, and data complementary program
KR20150049836A (en) * 2013-10-31 2015-05-08 한국해양과학기술원 Ships monitoring apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003269957A (en) * 2002-03-18 2003-09-25 Mitsubishi Space Software Kk Position correction device and position correction method for satellite image
JP2003288698A (en) * 2002-03-27 2003-10-10 Mitsui Eng & Shipbuild Co Ltd Nearby vessel information integrating method and device
JP2015036832A (en) * 2013-08-12 2015-02-23 株式会社日立ソリューションズ Data complementary device, data complementary method, and data complementary program
KR20150049836A (en) * 2013-10-31 2015-05-08 한국해양과학기술원 Ships monitoring apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020091159A1 (en) * 2018-11-02 2020-05-07 한국항공우주연구원 Method and device for correcting image sensor misalignment by using ship identification information

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