JP2017133861A - System for calibrating installation angle of antenna and method for calibrating installation angle of antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for calibrating the installation angle of an antenna and a method for calibrating the installation angle of an antenna in which an error in the installation angle of an antenna due to the strain, etc., of the antenna is taken into account.SOLUTION: The system for calibrating the installation angle of an antenna comprises: an angle measurement device 30 for measuring the installation angle α of the antenna 20 of a radar device 10; a radar device 10 for observing an observation object 3; and an arithmetic-logic device 40. The arithmetic-logic device 40 acquires first data that indicates an installation position along the first direction of the antenna 20. The arithmetic-logic device 40 acquires second data that indicates the position of the observation object 3. The arithmetic-logic device 40 calculates third data that indicates the relative position of the observation object 3 to the antenna 20 on the basis of the received data that is received from the radar device 10. The arithmetic-logic device 40 calculates a virtual position P1 of the antenna 20 on the basis of the third data while using the position of the observation object 3 indicated by the second data as a reference position. Furthermore, the arithmetic-logic device 40 calculates an installation angle calibration value α' of the antenna 20 on the basis of the virtual position P1 and the first data.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an antenna installation angle calibration system and an antenna installation angle calibration method.

  A mobile radar device may be used. When a mobile radar device is used, the installation position of the radar device can be acquired using a GPS (Global Positioning System). The installation angle of the antenna of the radar apparatus can be measured by a gyro sensor.

  However, when the installation position is calculated using GPS, a position measurement error of about 1 to 20 m may occur. In addition, regarding the antenna installation angle measured by the gyro sensor, an angle measurement error of the gyro sensor may occur, and the influence of the error due to the distortion of the antenna surface is not reflected in the antenna installation angle. .

  As a related technique, Patent Document 1 discloses a data calibration method for a radar apparatus. In the data calibration method of the radar apparatus described in Patent Document 1, a certain area is irradiated by a radar pulse transmitted from a ground radar apparatus installed on the earth. The scattered wave of the radar pulse is simultaneously observed by the ground radar device and the satellite-borne radar device in space. Then, the observation data obtained by the ground radar device is compared with the observation data obtained by the satellite-borne radar device, and the data is calibrated based on the comparison.

Japanese Patent Publication No. 2-27628

  An object of the present invention is to provide an antenna installation angle calibration system and an antenna installation angle calibration method in consideration of an antenna installation angle error caused by antenna distortion or the like.

  These objects and other objects and benefits of the present invention can be easily confirmed by the following description and the accompanying drawings.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the embodiments for carrying out the invention. These numbers and symbols are added with parentheses for reference in order to show an example of the correspondence between the description of the claims and the mode for carrying out the invention. Accordingly, the claims should not be construed as limiting due to the bracketed description.

  In some embodiments, an antenna installation angle calibration system observes an observation object (3) and an angle measurement device (30) that measures an installation angle (α) of an antenna (20) of a radar device (10). The radar apparatus (10) and the arithmetic unit (40) are provided. The said arithmetic unit (40) acquires the 1st data which show the installation position along the 1st direction of the said antenna (20). The arithmetic unit (40) acquires second data indicating the position of the observation object (3). The arithmetic unit (40) calculates third data indicating a relative position of the observation object (3) with respect to the antenna (20) based on reception data received from the radar device (10). The arithmetic unit (40) uses the position of the observation object (3) indicated by the second data as a reference position, and based on the third data, calculates the virtual position (P1) of the antenna (20). calculate. The arithmetic unit (40) calculates an installation angle calibration value (α ′) of the antenna (20) based on the virtual position (P1) and the first data.

  In the antenna installation angle calibration system, the computing device (40) is based on a difference between a position along the first direction of the virtual position (P1) and the installation position indicated by the first data. The installation angle calibration value (α ′) of the antenna (20) may be calculated.

  In the antenna installation angle calibration system, the arithmetic unit (40) is configured to connect the antenna (20) and the observation object (3) based on the reception data received from the radar device (10). A first distance (L) indicating a distance may be calculated. The arithmetic unit (40) is under a constraint that a distance between the corrected virtual position (P2) of the antenna (20) and the observation object (3) is the first distance (L). The corrected virtual position (P2) of the antenna may be calculated by correcting the virtual position (P1) of the antenna. The computing device (40) calibrates the installation angle of the antenna (20) based on the virtual position (P1), the corrected virtual position (P2), and the position of the observation object (3). The value (α ′) may be calculated.

  In the antenna installation angle calibration system, the calculation device (40) includes a straight line connecting the corrected virtual position (P2) and the observation object (3), the virtual position (P1), and the observation object. The installation angle calibration value (α ′) of the antenna may be calculated based on an angle (β) formed by a straight line connecting (3).

  In the antenna installation angle calibration system, the calculation device (40) may specify a three-dimensional position of the antenna based on the corrected virtual position (P2).

  In the antenna installation angle calibration system, the first direction may be a vertical direction.

  The antenna installation angle calibration system may further include a moving body to which the antenna (20) is attached.

  In some embodiments, an antenna installation angle calibration method includes obtaining a first data indicating an installation position along a first direction of an antenna (20) of a radar apparatus (10), and an angle measurement apparatus (30). Using the radar device (10), obtaining the installation angle (α) of the antenna (20), obtaining second data indicating the position of the observation object (3), and the radar device (10), While obtaining the third data indicating the relative position of the observation object (3) with respect to the antenna (20), and using the position of the observation object (3) indicated by the second data as a reference position, The step of calculating the virtual position (P1) of the antenna (20) based on the third data, and the installation of the antenna based on the virtual position (P1) of the antenna (20) and the first data angle Comprising a calibration value calculation step of calculating a positive value (α ').

  The antenna installation angle calibration method may include a step of acquiring fourth data indicating the position of the second observation object (3-2). Moreover, the process which acquires the 5th data which show the relative position of the said 2nd observation target object (3-2) with respect to the said antenna (20) using the said radar apparatus (10) may be provided. Further, based on the fifth data, the second virtual position (P1-2) of the antenna (20) is used while using the position of the second observation object (3-2) indicated by the fourth data as a reference position. ) May be provided. Further, a second calibration value calculation that calculates an installation angle second calibration value (α ″) of the antenna based on the second virtual position (P1-2) of the antenna (20) and the first data. A process may be provided. And a step of calculating a final calibration value of the installation angle of the antenna (20) based on the installation angle calibration value (α ′) and the second installation angle calibration value (α ″). Also good.

  According to the present invention, it is possible to provide an antenna installation angle calibration system and an antenna installation angle calibration method in consideration of an antenna installation angle error caused by antenna distortion or the like.

FIG. 1 is a diagram for explaining an assumed position identification error of a target object in the case where the installation position of an antenna of a radar apparatus is identified using GPS. FIG. 2 is a diagram for explaining an assumed position specifying error of a target object when an antenna installation angle of a radar apparatus is specified using an angle measuring apparatus such as a gyro sensor. FIG. 3 is a diagram for explaining the outline of the antenna installation angle calibration system and the antenna installation angle calibration method according to the first embodiment. FIG. 4 is a functional block diagram schematically showing the function of the antenna installation angle calibration system. FIG. 5 is a flowchart showing a method of calibrating the antenna installation angle. FIG. 6 is a diagram for explaining the outline of the antenna installation angle calibration system and the antenna installation angle calibration method according to the second embodiment. FIG. 7A is a flowchart showing a method of calibrating the antenna installation angle in the second embodiment. FIG. 7B is a flowchart illustrating a method of calibrating the antenna installation angle in the second embodiment. FIG. 8 is a diagram schematically illustrating an antenna installation angle calibration system according to the third embodiment. FIG. 9 is a diagram schematically illustrating an antenna installation angle calibration system according to the fourth embodiment. FIG. 10 is a diagram schematically illustrating an antenna installation angle calibration system according to the fifth embodiment.

  Hereinafter, a moving object observation system and a moving object observation method according to embodiments will be described with reference to the accompanying drawings. In the accompanying drawings, the same or similar components may be referred to by the same or corresponding reference numerals. Further, the embodiment will be described using a two-dimensional coordinate system so as not to complicate the description. However, it is obvious that the embodiment can be applied by extending to three dimensions. Although the extension to three dimensions can be performed based on the ordinary knowledge of those skilled in the art, information for extending to the three dimensions is also provided as appropriate in the specification.

(Matters recognized by the inventor)
With reference to FIG. 1, a description will be given of the position specifying error of the target object 1 that is assumed when the installation position of the antenna 20 of the radar apparatus 10 is specified using GPS. The radar apparatus 10 includes an antenna 20. The antenna 20 transmits radar waves and receives radar waves. In the example illustrated in FIG. 1, the antenna installation angle is an angle γ. The antenna installation angle may mean an angle formed between the horizontal direction and the antenna directing direction D (for example, a direction perpendicular to the antenna surface at the center of the antenna). In FIG. 1, it is assumed that the actual installation position of the antenna 20 is the position A and the installation position of the antenna 20 calculated by the GPS is the position B. In the example illustrated in FIG. 1, the detection angle of the target object 1 (for example, a flying object that is a threat object) (for example, the angle formed by the antenna directivity direction D and the direction from the antenna 20 toward the target object 1). Is the angle θ. Further, the distance to the target object 1, that is, the distance between the antenna 20 and the target object 1 is a distance L. In the example illustrated in FIG. 1, when the antenna installation position is specified using GPS, the position of the target object 1 is indicated by a broken line instead of the position E (actual position) indicated by a solid line. It will be calculated that it is in the position F.

  Next, a position specifying error of the target object 1 that is assumed when the installation angle of the antenna 20 of the radar apparatus 10 is specified using an angle measuring device such as a gyro sensor will be described with reference to FIG. In the example illustrated in FIG. 2, the actual installation angle of the antenna 20 is the angle γ. In other words, the antenna 20 exists at the position indicated by the solid line J. On the other hand, in the example shown in FIG. 2, the installation angle of the antenna specified by the angle measuring device is an angle γ ′ (an angle formed by the antenna directing direction D ′ and the horizontal direction). In other words, when the antenna installation angle is calculated based on the information from the angle measurement device, the antenna virtually exists at the angle indicated by the broken line K. In the example illustrated in FIG. 2, the radar apparatus 10 detects that the target object 1 exists in the direction indicated by the angle θ. Further, the radar apparatus 10 calculates that the distance between the radar apparatus 10 and the target object 1 is the distance L. In the example shown in FIG. 2, since there is a measurement error of the antenna installation angle (difference between the angle γ and the angle γ ′), the position of the target object 1 is at the position E (actual position) indicated by the solid line. Rather, it is calculated to be at the position G indicated by the broken line.

  The measurement error of the antenna installation angle occurs due to, for example, distortion of the antenna surface. The error due to the distortion of the antenna surface is, for example, about 0.01 ° (0.01 deg.). In addition, the measurement error of the antenna installation angle is caused by, for example, a pointing error (an error caused by a shift in the antenna directing direction due to the weight of the antenna). The pointing error is, for example, about 0.01 ° (0.01 deg.). When the antenna 20 of the radar apparatus is covered with a radio wave transmissive dome, a radome error is included in the error of the antenna installation angle. The radome error is an error due to the radar wave being distorted by the dome. The radome error is, for example, about 0.01 ° (0.01 deg.).

  For example, when the distance L between the target object 1 and the antenna 20 is 500 km, the target object position specifying error due to the measurement error of the antenna installation angle is 260 m with reference to the following formula (1). There is a risk of becoming.

(Equation 1)
500 km × tan {0.01 ° (surface distortion) + 0.01 ° (pointing error) +
0.01 ° (radome error)} = 260 m (1)

  Therefore, particularly when the distance between the target object 1 and the radar apparatus is a long distance (for example, 50 km or more, 100 km or more, or 300 km or more), the effect obtained by calibrating the antenna installation angle is large. For example, it is assumed that the radar device 10 is used as an air defense radar. As will be described later, in the embodiment, the position of the target object 1 (threat object) can be specified with high accuracy by appropriately calibrating the installation angle of the antenna. As a result, it is possible to arrange personnel having a mission of air defense, moving bodies (aircrafts, ships, vehicles, etc.), and flying objects for interception (intercepting missiles, etc.) at more suitable positions. In addition, based on the position of the target object 1 that is specified with high accuracy, the meeting position between the target object 1 and the intercepting weapon (intercepting missile, intercepting laser, etc.) can be calculated more accurately. When flying an interceptor missile toward a more precise meeting position, the missile attitude change required for the missile terminal guidance (guide the missile toward the target object using the sensor installed on the missile) It's small. As a result, the performance required for the missile can be reduced. For example, the size of the missile can be reduced by reducing the amount of fuel mounted on the missile. As a result, the operation of the interceptor missile is facilitated, and the manufacturing cost or the operation cost of the interceptor missile is reduced.

  In some cases, a plurality of pieces of information obtained by using a plurality of radar devices are integrated to detect the target object 1 or perform a cooperative battle. In this case, if the position of the target object 1 (threat object) cannot be specified with high accuracy, the target object detected by the first radar device and the target object detected by the second radar device are the same. It is not possible to determine whether the target object is one of these target objects or two different target objects. From this point of view, the usefulness of appropriately calibrating the installation angle of the antenna can be grasped.

(First embodiment)
The first embodiment will be described below. FIG. 3 is a diagram for explaining the outline of the antenna installation angle calibration system 5 and the antenna installation angle calibration method according to the first embodiment. FIG. 4 is a functional block diagram schematically showing the function of the antenna installation angle calibration system 5.

  The antenna installation angle calibration system 5 includes a radar device 10, an antenna 20 that forms part of the radar device 10, an angle measurement device 30 that measures the installation angle α of the antenna 20, and an arithmetic device 40.

  The arithmetic device 40 acquires first data indicating an installation position along the first direction of the antenna. The first direction may be a vertical direction or another direction. More specifically, the installation position along the first direction of the antenna is a position M along the first direction of the representative point 22 of the antenna. The position of the representative point 22 is arbitrary. When the first direction is the vertical direction, the position M along the first direction is the altitude of the representative point 22, for example, the absolute altitude (altitude above sea level) of the representative point 22, or the representative point 22 from the ground. Altitude.

  The arithmetic device 40 receives the data indicating the antenna installation angle α from the angle measurement device 30, thereby acquiring the antenna installation angle α (measurement value of the installation angle).

  The arithmetic device 40 acquires second data indicating the position of the observation object 3. The observation object 3 is an object that gives a reference position. The observation object 3 may be, for example, a celestial body such as the moon (a celestial body to which radio waves from the earth reach), or an artificial satellite or the like existing in outer space. Data indicating the position (absolute coordinates) of the observation object 3 can be acquired from a database or another observation system.

  The arithmetic device 40 calculates third data indicating the relative position of the observation object 3 with respect to the antenna 20 based on the reception data received from the radar device 10. Based on the received data received from the radar device 10, the arithmetic device 40 makes a direction from the antenna 20 toward the observation object 3 (for example, between a direction from the antenna 20 toward the observation object 3 and a directivity direction of the antenna). Angle θ) is calculated. Further, the arithmetic device 40 calculates the distance L between the antenna 20 and the observation object 3 based on the reception data received from the radar device 10. The calculation of the distance L may be performed based on the difference between the transmission time of the radio wave from the antenna 20 and the reception time at which the antenna 20 receives the radio wave reflected by the observation object 3. Alternatively, the calculation of the distance L may be performed based on data from a distance measuring device (for example, a laser distance measuring device) included in the radar device 10.

  The computing device 40 calculates the virtual position of the antenna 20 based on the third data while using the position (absolute coordinates) of the observation object 3 indicated by the second data as the reference position. For example, when the third data includes the distance L and the angle θ, the virtual position of the antenna 20 can be calculated backward based on the distance L and the angle θ while using the position of the observation object 3 as the reference position. Is possible. In the example illustrated in FIG. 3, the position indicated by the broken line is the virtual position P <b> 1 of the antenna 20. For the antenna virtually existing at the virtual position P1, the position along the first direction of the representative point 22 of the antenna is the position N.

  Further, the arithmetic device 40 calculates a calibration value α ′ of the antenna installation angle based on the virtual position P1 and the first data (for example, data indicating the position M). In the example illustrated in FIG. 3, the magnitude of the deviation between the position M and the position N corresponds to the magnitude of the error in the antenna installation angle. In other words, if the antenna installation angle α calculated by the angle measuring device 30 is not an accurate value, the deviation between the position M and the position N becomes large. In the example shown in FIG. 3, the position N is located below the ground, and the virtual position P1 calculated backward from the reference position cannot be said to represent the accurate installation position of the antenna.

  In the example illustrated in FIG. 3, it is assumed that the value of the position M and the value of the distance L are relatively accurate values. For this reason, if the representative point 22 at the virtual position P1 is virtually rotated around the observation target 3 so that the position along the first direction of the representative point 22 coincides with the position M, more An accurate antenna installation position can be acquired. As a result of the virtual rotational movement, the position of the antenna 20 moves from the position indicated by the broken line to the position indicated by the solid line. The computing device 40 determines the position of the antenna indicated by the solid line as the corrected virtual position P2 obtained by the correction.

  Even when the embodiment is extended to three dimensions, the representative point 22 at the virtual position P1 is moved around the observation object 3 so that the position along the first direction of the representative point 22 coincides with the position M. Can be virtually rotated. In this case, for example, the virtual rotational movement may include a rotational movement on a plane parallel to the paper surface of FIG. 3 and a rotational movement on a surface perpendicular to the paper surface of FIG. In other words, an arbitrary point on the intersection line between the spherical surface having the radius L and the plane perpendicular to the first direction and passing through the position M centering on the position of the observation object 3 is a candidate for the corrected virtual position P2. It becomes. For example, the azimuth angle in the direction from the virtual position P1 toward the observation object 3 (the angle indicating the azimuth in the horizontal plane) and the azimuth angle in the direction from the corrected virtual position P2 toward the observation object 3 are equal. Based on the conditions, it is possible to determine the corrected virtual position P2 from among a plurality of candidates. Alternatively, a position closest to the virtual position P1 among the plurality of candidates may be determined as the corrected virtual position P2.

  The arithmetic unit 40 calculates the calibration value α of the antenna installation angle based on the angle β formed by the straight line connecting the corrected virtual position P2 and the observation object 3 and the straight line connecting the virtual position P1 and the observation object 3. 'May be calculated. The arithmetic device 40 determines, for example, a value (α−β) obtained by subtracting the angle β from the angle α as the calibration value α ′ of the antenna installation angle.

  Alternatively, the arithmetic unit 40 may calculate the corrected virtual position P2 of the antenna indicated by the solid line and the direction from the antenna 20 toward the observation target 3 (for example, the direction from the antenna 20 toward the observation target 3 and the antenna directivity direction). The directivity direction D of the antenna 20 may be calculated based on the angle θ between the two. Then, the arithmetic device 40 may determine an angle α ′ (for example, an angle formed between the horizontal direction and the directivity direction D) indicated by the antenna directivity direction D as the calibration value α ′ of the antenna installation angle. .

  Assume that the first direction is the vertical direction. In this case, when the height of the virtual position P1 (the height of the position N) is lower than the height (the height of the position M) indicated by the first data, the arithmetic device 40 decreases the value of the installation angle α. Thus, the calibration value α ′ of the installation angle may be calculated. Further, when the height of the virtual position (the height of the position N) is higher than the height indicated by the first data (the height of the position M), the arithmetic device 40 increases the value of the installation angle α. The installation angle calibration value α ′ may be calculated. However, when the height of the virtual position (the height of the position N) is substantially equal to the height indicated by the first data (the height of the position M), in other words, the arithmetic device 40, the height of the virtual position and the height of the virtual position. When the absolute value of the difference from the height indicated by one data is smaller than the first threshold value TH1, the installation angle calibration value α ′ = α may be calculated so that the value of the installation angle α is maintained (in other words, The installation angle does not have to be calibrated).

  Note that the computing device 40 may calculate the three-dimensional position of the antenna 20 based on the corrected virtual position P2 of the antenna indicated by the solid line. That is, the arithmetic device 40 may calculate the three-dimensional position of the antenna 20 based on the position (absolute position) of the observation object 3, the distance L, and the first data (for example, the position M).

  In the first embodiment, the antenna installation angle is effectively calibrated. As a result, antenna installation angle errors (including errors due to the above-mentioned surface distortion, pointing errors, radome errors, etc.) can be corrected effectively. When a target object (threat object) is observed using a radar apparatus after calibration by the antenna installation angle calibration system in the first embodiment, the position specifying error of the target object (threat object) is reduced.

  In the first embodiment, it is additionally possible to calculate the three-dimensional position of the antenna. As a result, the GPS device can be omitted. Alternatively, the three-dimensional position of the antenna calculated using the GPS device is effectively calibrated based on the three-dimensional position of the antenna calculated using the antenna installation angle calibration system of the first embodiment. It becomes possible to do.

  In the first embodiment, the antenna installation angle and / or the three-dimensional position of the antenna are effectively calibrated. As a result, when the target object is observed using the radar apparatus, the position specifying error of the target object is reduced. For this reason, it is possible to reduce the antenna performance and / or the manufacturing accuracy of the antenna in consideration of the effect of reducing the position specifying error. As a result, the antenna can be reduced in size and / or the manufacturing cost of the antenna can be reduced.

  With reference to FIG. 4, each component of the antenna installation angle calibration system will be described in more detail. The antenna installation angle calibration system 5 includes a radar device 10, an antenna 20, an angle measurement device 30, a calculation device 40, and a storage device 50. The antenna installation angle calibration system 5 may include a first direction position calculation device 60 and / or a GPS device 70. The antenna installation angle calibration system 5 may include an input device 80 and / or an output device 90.

  The radar apparatus 10 is an apparatus for specifying the position of the target object 1 (threat object). The radar apparatus 10 includes a circuit 12 and an antenna 20. The circuit 12 may include a radar wave generation circuit that generates a radar wave and a reception circuit that receives the reflected radar wave reflected by the target object 1. The circuit 12 and a power source (not shown) that supplies power to the circuit are electrically connected. The circuit 12 and the antenna 20 are electrically connected, and the antenna 20 is configured to emit a radar wave toward the target object 1. The antenna 20 may be an antenna for AESA radar, for example. Note that AESA is an abbreviation for Active electronically scanned array radar. An antenna for an AESA radar includes, for example, a circuit 12 (transmitter, receiver, phase converter, etc.) for each antenna element. In an antenna for an AESA radar, a pointing error or the like occurs due to distortion or the like of the element attachment surface. However, if the antenna installation angle calibration system according to the first embodiment is used, the pointing error and the like are effectively corrected. The antenna 20 may be a parabolic antenna, or another type of antenna having high directivity, such as a Yagi antenna, a logarithmic periodic antenna, an axial mode helical antenna, a conical spiral antenna, or a horn antenna.

  The angle measuring device 30 is a device that measures the orientation of the antenna 20. The angle measuring device 30 measures, for example, an angle formed by a directivity direction of the antenna 20 and a reference direction (for example, a horizontal direction). When the embodiment is extended to three dimensions, the angle measuring device 30 corresponds to, for example, the angle of attack of the antenna (the angle between the antenna directing direction and the horizontal plane) and the antenna azimuth (the antenna directing direction). The direction in the horizontal plane to be measured, in other words, the direction obtained by projecting the directivity direction of the antenna onto the horizontal plane) may be measured. In the example shown in FIG. 4, at least a part of the angle measuring device 30 is provided so as to be rotatable around the pivot 24 together with the antenna 20. The angle measuring device 30 may include, for example, a gyro sensor. Data measured by the angle measuring device 30 (data corresponding to the antenna installation angle) is transmitted to the computing device 40 via wired or wireless.

  The first direction position calculation device 60 is a device that calculates an installation position of the antenna (antenna representative point) along the first direction. When the first direction is the vertical direction, the first direction position calculation device 60 may be an altimeter (for example, a barometric altimeter, a radio altimeter, or the like). Alternatively, the first direction position calculation device 60 uses position data in the horizontal plane acquired by the GPS device 70 and map data (terrain data indicating the correspondence between the position in the horizontal plane and the ground altitude). Thus, the altitude of the antenna may be calculated. When an antenna is installed on a flat ground or on a land with a small inclination, the position data acquired by the GPS device 70 is obtained even when the position measurement error in the horizontal plane by the GPS device 70 is about 20 m. The calculation error of the ground surface height obtained by collating with the map data is relatively small. Then, the first direction position calculation device 60 adds the distance between the ground and the representative point of the antenna to the calculated ground height, thereby setting the installation position along the first direction of the antenna (the antenna installation height). ) Is calculated.

  The first direction position calculation device 60 transmits the calculated data to the arithmetic device 40 via wired or wireless. Note that the arithmetic device 40 may have a part or all of the functions of the first direction position calculation device 60. Note that the first direction position calculation device 60 is arranged along a second direction different from the first direction of the antenna (representative point of the antenna) in addition to the installation position of the antenna (representative point of the antenna) along the first direction. The installation position may be calculated. However, the arithmetic unit 40 can calculate the calibration value α ′ of the antenna installation angle without using data of the installation position along the second direction different from the first direction of the antenna (antenna representative point). It is.

  The GPS device 70 acquires position data of the antenna 20 through communication with a GPS satellite. The GPS device 70 transmits the acquired data to the arithmetic device 40 via a wired or wireless connection.

  The arithmetic device 40 includes a hardware processor such as a CPU. The arithmetic device 40 functions as first data acquisition means 41 that acquires first data indicating the installation position of the antenna 20 along the first direction by executing a program stored in the storage device 50. The first data acquisition unit 41 may acquire the first data by receiving the antenna installation altitude data from the first direction position calculation device 60. Alternatively, the first data acquisition unit 41 calculates the antenna installation altitude based on the antenna position data in the horizontal plane received from the GPS device 70 and the map data stored in the storage device 50, and calculates The installed altitude of the antenna may be acquired as the first data.

  The arithmetic device 40 also functions as an installation angle acquisition unit 42 that acquires the installation angle of the antenna by executing a program stored in the storage device 50. The installation angle acquisition unit 42 may acquire the antenna installation angle α by receiving data indicating the antenna installation angle from the angle measurement device 30.

  In addition, the arithmetic device 40 functions as a second data acquisition unit 43 that acquires second data indicating the position of the observation object 3 by executing a program stored in the storage device 50. The second data acquisition unit 43 may acquire the second data by receiving data indicating the position (absolute position) of the observation object 3 from a system different from the antenna installation angle calibration system 5. Alternatively, when orbit data of the observation object 3 (celestial body or artificial satellite) is stored in the storage device 50, the arithmetic unit 40 uses the orbit data stored in the storage device 50 and the current time. Based on this, the current position of the observation object 3 may be calculated, and the calculated current position may be acquired as the second data.

  The arithmetic device 40 also functions as third data acquisition means 44 that acquires third data indicating the relative position of the observation object 3 with respect to the antenna 20 by executing a program stored in the storage device 50. Based on the data received from the radar apparatus 10, the third data acquisition unit 44 is configured to position the observation target 3 relative to the antenna 20 (for example, the distance L between the antenna 20 and the observation target 3, and the antenna 20 The direction (attack angle and azimuth angle) of the observation object 3 when viewed from above may be calculated, and the calculated relative position may be acquired as the third data.

  The arithmetic device 40 also functions as a virtual position calculation unit 45 that calculates the virtual position of the antenna by executing a program stored in the storage device 50. The virtual position calculation means 45 is based on the third data indicating the relative position of the observation object 3 with respect to the antenna under the condition that the position of the observation object 3 indicated by the second data is the reference position. Is calculated. For example, when the third data includes the distance L and the direction of the observation object 3 when viewed from the antenna 20, the virtual position calculation unit 45 has the condition that the position of the observation object 3 is the reference position. Based on the distance L and the direction of the observation object 3 when viewed from the antenna 20, the virtual position P1 of the antenna 20 is calculated backward.

  The arithmetic device 40 also functions as a calibration value calculation means 46 that calculates a calibration value of the antenna installation angle by executing a program stored in the storage device 50. The calibration value calculation means 46 calculates the calibration value α ′ of the antenna installation angle based on the virtual position of the antenna 20 and the first data indicating the installation position (for example, the position M) of the antenna 20 in the first direction. Is calculated.

  First, the calibration value calculation means 46 calculates the corrected virtual position P2 of the antenna. For example, the calibration value calculation means 46 corrects the virtual position P1 of the antenna 20 under the constraint that the distance between the corrected virtual position P2 of the antenna 20 and the observation object 3 is the distance L, The corrected virtual position P2 of the antenna is calculated. More specifically, the calibration value calculation means 46 performs the first direction of the corrected virtual position P2 under the constraint that the distance between the corrected virtual position P2 of the antenna 20 and the observation object 3 is the distance L. And the position along the first direction of the antenna indicated by the first data (for example, position M) is the position along the first direction of the virtual position P1 (for example, position N). And the corrected virtual position P2 of the antenna is calculated so as to be smaller than the difference between the antenna and the installation position (for example, position M) along the first direction of the antenna indicated by the first data.

  The calibration value calculation means 46 may specify the three-dimensional position of the antenna based on the corrected virtual position P2 of the antenna. For example, the calibration value calculation means 46 may determine the post-correction virtual position P2 of the antenna as the three-dimensional position of the antenna. Alternatively, when the calculation device 40 calculates a plurality of corrected virtual positions P2 corresponding to a plurality of observation objects, the intermediate position or the center of gravity position of the plurality of corrected virtual positions P2 is calculated using the antenna position. You may determine as a three-dimensional position. The calibration value calculation means 46 calculates the distance between the three-dimensional position of the antenna acquired by the GPS device 70 and the corrected virtual position P2 of the antenna, and the distance is the second threshold TH3 (for example, 10 m). , 20 m or 30 m or less), the three-dimensional position of the antenna may be determined based on the calculated corrected virtual position P2. That is, the arithmetic device 40 determines the reliability of the calculated corrected virtual position P2 based on the three-dimensional position of the antenna acquired by the GPS device 70, and determines whether or not the calculated corrected virtual position P2 is accepted. May be.

  Next, the calibration value calculation means 46 calculates the calibration value α ′ of the antenna installation angle based on the virtual position P1, the corrected virtual position P2, and the position of the observation object 3. For example, the calibration value calculation means 46 determines the antenna installation angle based on the angle β formed by the straight line connecting the corrected virtual position P2 and the observation object 3 and the straight line connecting the virtual position P1 and the observation object 3. The calibration value α ′ is calculated.

  The storage device 50 stores various programs and temporarily stores calculation data necessary for the calculation device 40 to perform calculations.

  The input device 80 includes, for example, a keyboard and a mouse. The input device 80 transmits data input by the user to the arithmetic device 40.

  The output device 90 includes, for example, a display and a printer. The output device 90 receives data such as an antenna installation angle calibration value α ′ from the arithmetic device 40 and outputs (displays) the received data.

(Antenna installation angle calibration method)
A method for calibrating the antenna installation angle will be described with reference to FIG. FIG. 5 is a flowchart showing a method of calibrating the antenna installation angle. The antenna installation angle calibration method is executed by using the antenna installation angle calibration system 5 described above.

  In the first step S1, the arithmetic device 40 (first data acquisition means 41) acquires first data indicating the installation position along the first direction of the antenna.

  In the second step S <b> 2, the arithmetic device (installation angle acquisition means 42) receives data indicating the antenna installation angle α from the angle measurement device 30.

  In 3rd step S3, the arithmetic unit 40 performs the observation object selection process which selects the observation object 3. FIG. The computing device 40 may automatically select the observation object 3 that can be observed from the position based on the position of the antenna 20 acquired by the GPS device 70 and the current time. Alternatively, the user may input data indicating the observation target object 3 to the input device 80, and the calculation device 40 may select the observation target object 3 based on the input data. In addition, when the observation object 3 is determined in advance, the third step S3 may be omitted.

  In the fourth step S4, the arithmetic device 40 (second data acquisition means 43) acquires second data indicating the position of the observation object 3. The observation object 3 is an object that gives a reference position.

  In the fifth step S <b> 5, the arithmetic device 40 (third data acquisition unit 44) calculates third data indicating the relative position of the observation object 3 with respect to the antenna 20 based on the reception data received from the radar device 10. For example, the arithmetic device 40 calculates the direction from the antenna 20 toward the observation object 3 and the distance L between the antenna 20 and the observation object 3.

  The order in which the first step S1, the second step S2, the third step S3, the fourth step S4, and the fifth step S5 are executed is arbitrary. However, when the third step S3 is executed, the third step S3 needs to be executed before the fourth step S4.

  In the sixth step S6, the computing device 40 (virtual position calculation means 45) uses the position (absolute coordinates) of the observation object 3 indicated by the second data as the reference position, and based on the third data, A virtual position P1 is calculated.

  In the seventh step S7, the arithmetic unit 40 (calibration value calculation means 46) calculates the calibration value α of the antenna installation angle based on the virtual position P1 of the antenna and the first data (for example, data indicating the position M). 'Is calculated. Note that the specific method of calculating the calibration value α ′ is as described above, and thus the repeated description is omitted. The absolute value of the difference between the position (for example, position N) along the first direction of the virtual position P1 of the antenna and the position (for example, position M) indicated by the first data is greater than the first threshold value TH1. When it is small, the arithmetic unit 40 may not calibrate the antenna installation angle α.

  In addition, in 7th step S7, the arithmetic unit 40 (calibration value calculation means 46) is based on the position (absolute position) of the observation target object 3, the distance L, and 1st data in addition. The three-dimensional position may be calculated. Note that the specific method for calculating the three-dimensional position of the antenna 20 is as described above, and thus the repeated description is omitted.

  After completing the calibration of the antenna installation angle, the arithmetic unit 40 receives the data received from the radar apparatus 10 that detects the target object 1 (threat object), the calibration value α ′ of the antenna installation angle, and the three-dimensional position of the antenna 20. Based on the above, the position of the target object 1 is specified. In the first embodiment, the antenna installation angle is calibrated by the above-described method. For this reason, it becomes possible to specify the position of the target object 1 with higher accuracy using the radar device 10. In addition, in the first embodiment, instead of the calculation of the three-dimensional position of the antenna by the GPS device 70 or in addition to the calculation of the three-dimensional position of the antenna by the GPS device 70, Based on the distance L and the first data, the three-dimensional position of the antenna is calculated. Therefore, since the three-dimensional position of the antenna is specified with higher accuracy, the position of the target object 1 can be specified with higher accuracy using the radar device 10.

  The first step S1 to the seventh step S7 described above may be executed a plurality of times, and the calibration value α ′ for the antenna installation angle may be calculated a plurality of times. In this case, the arithmetic unit 40 determines a final calibration value of the antenna installation angle based on the plurality of calculated calibration values α ′. For example, the arithmetic unit 40 determines the average value of the plurality of calibration values α ′ as the final calibration value of the antenna installation angle. In addition, the above-described first step S1 to seventh step S7 may be executed a plurality of times, and the three-dimensional position of the antenna may be calculated a plurality of times. In this case, the arithmetic device 40 finally determines the three-dimensional position of the antenna based on the calculated three-dimensional positions. For example, the arithmetic unit 40 may determine the center of gravity of a plurality of three-dimensional positions as the final three-dimensional position of the antenna.

(Second Embodiment)
The antenna installation angle calibration system and the antenna installation angle calibration method according to the second embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a diagram for explaining the outline of the antenna installation angle calibration system 5 and the antenna installation angle calibration method according to the second embodiment. 7A and 7B are flowcharts showing a method for calibrating the antenna installation angle in the second embodiment.

  In the second embodiment, the antenna installation angle α is calibrated using the second observation object 3-2 in addition to the observation object 3. In addition, the component which comprises the antenna installation angle calibration system 5 in 2nd Embodiment is the same as the component which comprises the antenna installation angle calibration system in 1st Embodiment. That is, the antenna installation angle calibration system 5 shown in FIG. 4 can be adopted as the antenna installation angle calibration system 5 in the second embodiment. For this reason, the repeated description about each component of the calibration system 5 of an antenna installation angle is abbreviate | omitted.

  With reference to FIG. 6, the second observation target 3-2 is an object different from the observation target 3. The second observation object 3-2 may be, for example, a celestial body such as the moon (a celestial body to which radio waves from the earth reach), or an artificial satellite or the like existing in outer space. Data indicating the position (absolute coordinates) of the second observation object 3-2 can be obtained from a database or another observation system.

  The second observation object 3-2 is an observation object observed after the observation object 3 is observed. More specifically, the second observation target 3-2 is an observation target observed after execution of the first step S1 to the seventh step S7 described with reference to FIG.

  With reference to FIG. 6, FIG. 7A, and FIG. 7B, the antenna installation angle calibration method in the second embodiment will be described. Since the first step S1 to the seventh step S7 are the same as the first step S1 to the seventh step S7 in the antenna installation angle calibration method of the first embodiment, the repetitive description will be omitted.

  In 8th step S8, the arithmetic unit 40 acquires the 1st data which show the installation position along the 1st direction of the antenna 20. FIG. In addition, when using the 1st data acquired in 1st step S1 as 1st data, 8th step S8 is abbreviate | omitted. In the ninth step S <b> 9, the arithmetic device 40 receives data indicating the installation angle α of the antenna 20 from the angle measurement device 30. In addition, when using the data acquired in 2nd step S2 as data which show the installation angle (alpha), 9th step S9 is abbreviate | omitted.

  In the tenth step S10, the arithmetic unit 40 executes a second observation object selection process for selecting the second observation object 3-2. The computing device 40 may automatically select the second observation object 3-2 that can be observed from the position based on the position of the antenna acquired by the GPS device 70 and the current time. The second observation object 3-2 is an object different from the observation object 3.

  In the eleventh step S11, the arithmetic unit 40 acquires fourth data indicating the position of the second observation object 3-2. The second observation object 3-2 is an object that gives a reference position (second reference position). The fourth data acquisition method is the same as the second data acquisition method except that the observation target is not the observation target 3 but the second observation target 3-2.

  In the twelfth step S <b> 12, the arithmetic device 40 calculates fifth data indicating the relative position of the second observation object 3-2 with respect to the antenna 20 based on the reception data received from the radar device 10. For example, the arithmetic device 40 calculates the direction from the antenna 20 toward the second observation object 3-2 and the distance L2 between the antenna 20 and the second observation object 3-2. The fifth data acquisition method is the same as the third data acquisition method except that the observation target is not the observation target 3 but the second observation target 3-2. In FIG. 6, the angle θ <b> 2 is an angle formed between the direction from the antenna 20 toward the second observation target 3-2 and the directivity direction of the antenna.

  The order in which the above-described eighth step S8, ninth step S9, tenth step S10, eleventh step S11, and twelfth step S12 are executed is arbitrary. However, when the tenth step S10 is executed, the tenth step S10 needs to be executed before the eleventh step S11.

  In the thirteenth step S13, the computing device 40 uses the position (absolute coordinates) of the second observation object 3-2 indicated by the fourth data as the reference position, and uses the second virtual of the antenna 20 based on the fifth data. A position P1-2 is calculated. In the calculation method of the second virtual position P1-2, the observation target is not the observation target 3, but the second observation target 3-2, the second data is replaced with the fourth data, and the third data is the fifth. The method is the same as the calculation method of the virtual position P1 except that the data is replaced.

  In the fourteenth step S14, the arithmetic unit 40 calculates the second calibration value α ′ of the antenna installation angle based on the second virtual position P1-2 of the antenna and the first data (for example, data indicating the position M). 'Is calculated. The specific method of calculating the second calibration value α ″ is that the observation object is not the observation object 3 but the second observation object 3-2, the second data is replaced with the fourth data, Except for the point that the third data is replaced with the fifth data and the virtual position P1 is replaced with the second virtual position P1-2, the method is the same as the calculation method of the calibration value α ′.

  In the fourteenth step S14, the arithmetic device 40 additionally adds the three-dimensional antenna 20 based on the position (absolute position) of the second observation object 3-2, the distance L2, and the first data. The position may be calculated. Note that the specific method for calculating the three-dimensional position of the antenna 20 is as described above, and thus the repeated description is omitted.

  In the fifteenth step S15, the arithmetic unit 40 calculates a final calibration value of the antenna installation angle based on the calibration value α ′ and the second calibration value α ″. For example, the arithmetic device 40 may determine an average value of the calibration value α ′ and the second calibration value α ″ as the final calibration value of the antenna installation angle. In addition, the computing device 40 adds the first calculated position that is the three-dimensional position of the antenna calculated in the seventh step S7 and the second calculated position that is the three-dimensional position of the antenna calculated in the fourteenth step. Based on this, the final three-dimensional position of the antenna may be calculated. For example, the arithmetic device 40 may determine an intermediate position between the first calculation position and the second calculation position as the final three-dimensional position of the antenna.

  The second embodiment has the same effects as the first embodiment. In addition, in the second embodiment, the computing device 40 receives data received from the radar device 10 that detects the target object 1 (threat object), the antenna installation angle calibration value α ′, and the second calibration value α ′. The position of the target object 1 is specified based on 'and the three-dimensional position of the antenna 20. For this reason, it becomes possible to specify the position of the target object 1 with higher accuracy using the radar apparatus 10. Additionally, in the second embodiment, the three-dimensional position of the antenna is calculated based on the first calculation position and the second calculation position. Therefore, since the three-dimensional position of the antenna is specified with higher accuracy, the position of the target object 1 can be specified with higher accuracy using the radar apparatus 10.

  In the second embodiment, two observation objects are observed. Alternatively, three or more observation objects may be observed.

(Third embodiment)
A third embodiment will be described with reference to FIG. FIG. 8 is a diagram schematically illustrating the antenna installation angle calibration system 5 according to the third embodiment. In the third embodiment, the antenna installation angle calibration system 5 includes the vehicle 100 to which the antenna 20 is attached. In other respects, the third embodiment is the same as the first embodiment or the second embodiment. When the first direction is the vertical direction, the position M along the first direction is the altitude of the representative point 22 of the antenna 20, for example, the absolute altitude of the representative point 22 or the ground of the representative point 22. Of altitude.

(Fourth embodiment)
A fourth embodiment will be described with reference to FIG. FIG. 9 is a diagram schematically illustrating the antenna installation angle calibration system 5 according to the fourth embodiment. In the fourth embodiment, the antenna installation angle calibration system 5 includes a ship 200 to which the antenna 20 is attached. In other respects, the fourth embodiment is the same as the first embodiment or the second embodiment. When the first direction is the vertical direction, the position M along the first direction is the height of the representative point 22 of the antenna 20, for example, the absolute height of the representative point 22, or the water surface of the representative point 22 ( Altitude from sea level etc.

(Fifth embodiment)
The fifth embodiment will be described with reference to FIG. FIG. 10 is a diagram schematically illustrating the antenna installation angle calibration system 5 according to the fifth embodiment. In the fifth embodiment, the antenna installation angle calibration system 5 includes a flying object 300 (for example, an aircraft) to which the antenna 20 is attached. In other respects, the fifth embodiment is the same as the first embodiment or the second embodiment. When the first direction is the vertical direction, the position M along the first direction is the height of the representative point 22 of the antenna 20, for example, the absolute height of the representative point 22, or the ground of the representative point 22 or It is the altitude from the water surface.

  In the third to fifth embodiments, the antenna installation angle calibration system includes a moving body to which an antenna is attached. For this reason, after the moving body is moved, the antenna installation angle calibration method can be quickly executed without unloading the antenna or the like from the moving body. In addition, it is possible to quickly observe the target object using the radar apparatus whose antenna installation angle is calibrated.

  The present invention is not limited to the embodiments described above, and it is obvious that the embodiments can be appropriately modified or changed within the scope of the technical idea of the present invention. Various techniques used in each embodiment or modification can be applied to other embodiments or modifications as long as no technical contradiction arises.

1: Target object 3: Observation object 3-2: Second observation object 5: Calibration system 10: Radar apparatus 12: Circuit 20: Antenna 22: Representative point 24: Pivot 30: Angle measurement apparatus 40: Arithmetic apparatus 41: First data acquisition means 42: Installation angle acquisition means 43: Second data acquisition means 44: Third data acquisition means 45: Virtual position calculation means 46: Calibration value calculation means 50: Storage device 60: First direction position calculation apparatus 70 : GPS device 80: Input device 90: Output device 100: Vehicle 200: Ship 300: Flying object P1: Virtual position P1-2: Second virtual position P2: Virtual position after correction

Claims (9)

An angle measuring device for measuring the installation angle of the antenna of the radar device;
The radar device for observing an observation object;
An arithmetic unit, and
The arithmetic device acquires first data indicating an installation position along a first direction of the antenna,
The arithmetic device acquires second data indicating a position of the observation object,
The arithmetic device calculates third data indicating a relative position of the observation object with respect to the antenna based on reception data received from the radar device;
The arithmetic unit calculates the virtual position of the antenna based on the third data while using the position of the observation object indicated by the second data as a reference position.
The arithmetic device calculates an antenna installation angle calibration value based on the virtual position and the first data. Antenna calibration system for antenna installation angle. The calculation device calculates the installation angle calibration value of the antenna based on a difference between a position along the first direction of the virtual position and the installation position indicated by the first data. The antenna installation angle calibration system described. The arithmetic device calculates a first distance indicating a distance between the antenna and the observation object based on the reception data received from the radar device,
The arithmetic unit corrects the virtual position of the antenna under a constraint that a distance between the corrected virtual position of the antenna and the observation target is the first distance, and Calculating the corrected virtual position;
The antenna installation angle according to claim 1, wherein the arithmetic device calculates the installation angle calibration value of the antenna based on the virtual position, the corrected virtual position, and the position of the observation object. Calibration system. The calculation device calculates the installation angle calibration value of the antenna based on an angle formed by a straight line connecting the corrected virtual position and the observation object and a straight line connecting the virtual position and the observation object. The antenna installation angle calibration system according to claim 3. The antenna installation angle calibration system according to claim 3 or 4, wherein the arithmetic device specifies a three-dimensional position of the antenna based on the corrected virtual position. The antenna installation angle calibration system according to any one of claims 1 to 5, wherein the first direction is a vertical direction. The antenna installation angle calibration system according to any one of claims 1 to 6, further comprising a moving body to which the antenna is attached. Obtaining first data indicating an installation position along the first direction of the antenna of the radar device;
Obtaining an installation angle of the antenna using an angle measuring device;
Obtaining second data indicating the position of the observation object;
Using the radar apparatus to obtain third data indicating a relative position of the observation object with respect to the antenna;
Calculating the virtual position of the antenna based on the third data while using the position of the observation object indicated by the second data as a reference position;
A calibration value calculation step of calculating an antenna installation angle calibration value based on the virtual position of the antenna and the first data. An antenna installation angle calibration method. Obtaining fourth data indicating the position of the second observation object;
Using the radar apparatus to obtain fifth data indicating a relative position of the second observation object with respect to the antenna;
Calculating a second virtual position of the antenna based on the fifth data while using the position of the second observation object indicated by the fourth data as a reference position;
A second calibration value calculation step of calculating a second calibration value of the antenna installation angle based on the second virtual position of the antenna and the first data;
The antenna installation angle calibration method according to claim 8, further comprising: calculating a final calibration value of the installation angle of the antenna based on the installation angle calibration value and the second installation angle calibration value.

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