KR101565259B1 - Driving control method for non-stop satellite antenna and computer readable record-midium on which program for excuting method thereof - Google Patents

Abstract

The present invention relates to a method and an apparatus for controlling an operation of a non-stop satellite antenna and a program recording medium therefor. The method for controlling an operation of a non-stop satellite antenna according to one embodiment of the present invention comprises the steps of: calculating a geographic coordinate system of an antenna (LLH_(ANT)) by using a latitude, a longitude, an altitude and GPS coordinates by which an antenna is installed, and then converting LLH_(ANT) into a geocentric coordinate system (ECEF_(ANT)); calculating a geographic coordinate system of a satellite (LLH_(SAT)) by using TLE information, and then converting the LLH_(SAT) into a geocentric coordinate system of a satellite (ECEF_(SAT)); converting the ECEF_(ANT) and the ECEF_(SAT) into a northeast coordinate system of an antenna (ENU_(ANT)); converting the ENU_(ANT) to an antenna body coordinate system (BODY_(ANT)); and deriving an antenna installation angle by using the BODY_(ANT).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a driving control method for a non-geostationary satellite antenna,

The present invention relates to a non-geostationary-satellite antenna, and more particularly, to a method and apparatus for driving a non-geostationary-satellite antenna capable of stably driving at a tracking angle of 88 ° or more and a program recording medium therefor.

Unlike geostationary satellites, which are located at 36,000 km above the Earth, non-geostationary orbit satellites can be used in low orbit of dozens to thousands of kilometers with little signal transmission loss, high resolution and close observation, It is widely used in various fields of business such as military, science, earth exploration, meteorological observation, and navigation, and the number of launching satellites is increasing every year.

When tracking such non-geostationary satellites, the antenna must move and change direction. An antenna system with at least two axes of rotation is required in order to track an active non-stationary satellite and organically move the antenna.

Due to the structural constraints of the hardware, the control of the existing two - axis low - orbit satellite antenna system is subject to constraints in operating a path of 88 degrees or higher. In actual operation of an antenna system for a two-axis low earth orbit satellite, the pass may fail due to a high elevation angle.

In the case of non-geostationary satellites, the azimuth and elevation change rapidly with time, and the driving speed of the antenna system required to track the geostationary and elevation angles should be the same as that of non-geostationary satellites. As a result, in the case of a two-axis antenna, the driving speed of the azimuth axis and the elevation axis must be faster than the azimuth angle and the elevation angle.

Since the driving speed of the tracking antenna is an amount of change per hour, it is convenient to introduce a numerical calculation method. When the angle with time is f (t), the angular velocity f '(t) can be obtained by the following equation.

In the case of a non-geostationary satellite, the azimuthal velocity increases rapidly as the elevation angle increases with the above equation, and the azimuthal velocity increases to infinity when the maximum elevation angle is 90 °.

Figure 1 is a graphical representation of the azimuthal velocity versus the satellite path when the maximum elevation angle is 89.9 °.

As a result, if a non-geostationary satellite is tracked with a two-axis antenna, it can not be traced in the case of a path of a satellite having a maximum elevation angle.

Korean Patent Publication No. 2007-0031275

SUMMARY OF THE INVENTION It is therefore a general object of the present invention to provide a non-geostationary satellite antenna capable of substantially solving various problems caused by limitations and disadvantages of the prior art, And a program recording medium therefor.

It is yet another specific object of the present invention to provide a driving control method and apparatus for a non-stationary satellite antenna capable of stable driving at a tracking angle of 88 ° or more, and a program recording medium therefor.

The drive control of the non-stop wiseongyong antenna method according to one embodiment of the present invention to achieve this by using the latitude, longitude, altitude and the GPS coordinates of the antenna is installed, to obtain the geographic coordinate system of the antenna (LLH _ANT), of the LLH _ANT antenna Into a center coordinate system (ECEF _ANT ); Obtaining LLH _SAT of the satellite using the TLE information, and converting the LLH _SAT into a satellite center coordinate system (ECEF _SAT ) of the satellite; Converting the ECEF _ANT and the ECEF _SAT into a north-east coordinate system (ENU _ANT ) of an antenna; Converting the ENU _ANT into an antenna body coordinate system (BODY _ANT ); And deriving an antenna installation angle using the BODY _ANT .

In the driving control method for a non-geostationary satellite antenna according to an embodiment of the present invention, the method may further include a step of obtaining a true angle of two axes using the ENU _ANT .

In the driving control method for a non-geostationary satellite antenna according to an embodiment of the present invention, a process of converting the LLH _ANT into an earth center coordinate system (ECEF _ANT ) of an antenna may be performed by the following equation (1).

[Equation 1]

를 각각 의미한다.In Equation (1)

Respectively.

The process of converting the LLH _SAT into a satellite center coordinate system (ECEF _SAT ) in the driving control method of a non-geostationary satellite antenna according to an embodiment of the present invention includes the steps of calculating the starting point time, average angular acceleration, average angular acceleration, ascending node RA, eccentricity, perigee for each, the mean anomaly can be made of the process in which each, for receiving at least one of the average acceleration utilizing SGP4 model to calculate the X _{ECEF _ SAT,} Y _{ECEF _ SAT,} Z _{ECEF _ SAT} of the satellite .

In the driving control method for a non-geostationary satellite antenna according to an embodiment of the present invention, a process of converting the ECEF _ANT and the ECEF _SAT into an Northeast coordinate system (ENU _ANT ) of an antenna can be performed by the following equation (2).

&Quot; (2) "

In Equation 2 X _{ECEF _ SAT} are X, Y _ECEF the ECEF coordinates of the satellite _{_ SAT} is the ECEF coordinates of the satellite Y, Z _{ECEF _ SAT} is the ECEF coordinates of the satellite Z, X _{ECEF _ ANT} is ECEF coordinates of the antenna the X, Y _{ECEF _ ANT} is the ECEF coordinates of the antenna Y, Z _{ECEF _ ANT} is of Z, ENU _E ECEF coordinates of the antenna E is the ENU coordinate, ENU is the _N of the ENU coordinate, UU is the _U of the ENU coordinate, φ _r is the latitude of the ENU coordinate system reference point, and λ _r is the hardness of the ENU coordinate system reference point.

In the driving control method of a non-geostationary satellite antenna according to an embodiment of the present invention, a process of converting the ENU _ANT into an antenna body coordinate system (BODY _ANT ) can be performed by the following equation (3).

&Quot; (3) "

는 기울기,

는 트레인을 각각 나타낸다. In Equation (3), ENU _E E of the ENU coordinate, ENU _N is the _N of the ENU coordinate, ENU _U U, BODY _E of the ENU coordinate E of BODY coordinate, BODY _N is _N of BODY coordinate, BODY _U Of the BODY coordinate,

Lt; / RTI >

Respectively.

In the driving control method for a non-geostationary satellite antenna according to an embodiment of the present invention, a process of deriving an antenna installation angle using the BODY _ANT may be performed by Equation (4).

&Quot; (4) "

In Equation (4), BODY _E E of the BODY coordinate, BODY _N Are coordinates of the BODY N, _U is a BODY BODY coordinates U, R is the distance, Φ _{_ Mount ANT} is Mount_Azimuth, λ represents the Mount _Elevation _{ANT_Mount} antenna of each antenna.

In the driving control method of a non-geostationary satellite antenna according to an embodiment of the present invention, a process of calculating a true angle of two axes using the ENU _ANT can be performed by the following equation (5).

&Quot; (5) "

In Equation (5), ENU _E E, ENU _N of the ENU coordinate Of the ENU coordinate N, ENU _U Is the ENU coordinate U, R is the distance, Φ _{_ ANT} is _TRUE True_Azimuth, λ _{_ TRUE} antenna _ANT denotes a True_Elevation of the antenna.

According to the method and apparatus for driving the non-geostationary satellite antenna according to the present invention and the program recording medium therefor, it is possible to stably drive at a tracking angle of 88 ° or more, thereby enabling smooth satellite tracking.

Figure 1 is a graphical representation of the azimuthal velocity versus the satellite path when the maximum elevation angle is 89.9 °.
2 is a diagram showing an LLH coordinate system (geographical coordinate system).
Fig. 3 is a view showing an ECEF coordinate system (centroid coordinate system).
4 is a diagram showing an ENU coordinate system (northeast coordinate system).
5 is a diagram showing a BODY coordinate system (antenna body coordinate system).
6 is a flowchart illustrating a method of controlling the driving of a non-geostationary satellite antenna according to an embodiment of the present invention.
7 is a diagram showing a true angle of correction of two axes.
8 is a view showing a mount angle of three axes.
9 is a diagram illustrating a hardware configuration of a triaxial antenna according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In addition, the terms described below are defined in consideration of the functions of the present invention, and these may vary depending on the intention of the user, the operator, or the precedent. Therefore, the definition should be based on the contents throughout this specification.

The coordinate system required for operating the antenna according to the present invention includes an LLH coordinate system (geographical coordinate system), an ECEF coordinate system (centroid coordinate system), an ENU coordinate system (northeast coordinate system), and a BODY coordinate system (antenna coordinate system) Fig. 3 shows the ECEF coordinate system, Fig. 4 shows the ENU coordinate system, and Fig. 5 shows the BODY coordinate system.

- LLH coordinate system (geographical coordinate system):

* Latitude: the angle between the vertical line of the Earth's ellipsoid and the equator at a point

* Hardness: The angle between the plane perpendicular to the equator and the prime meridian, past a point.

* Altitude: the distance between the origin of the Earth's ellipsoid and the perpendicular point of the Earth's ellipsoid

- ECEF coordinate system (centroid coordinate system):

* Origin: the center of mass of the earth ellipsoid

* X axis: direction of intersection of prime meridian and equator from origin

* Y axis: direction of intersection of the equator with the prime meridian rotated 90 degrees to the east from the origin

* Z axis: From the center of the earth to the north pole

- ENU coordinate system (Northeast coordinate system):

* X _ENU Axis: East (East)

* Y _ENU axis: North direction (North)

* Z _ENU axis: X _ENU -Y _ENU perpendicular to the plane, in the opposite direction of the center of the earth

- BODY coordinate system (body coordinate system):

* Z _BODY axis: axis perpendicular to antenna body plane (aligned with Z _ENU axis)

* X _BODY axis: Z axis perpendicular to the _PLAT axis and having a tilt angle of 0 (aligned to the X _ENU axis)

* Y _BODY axis: Z axis perpendicular to the _PLAT axis and azimuth angle 0 (aligned to the Y _ENU axis)

 A procedure for creating a three-axis (azimuth, elevation, tilt) algorithm using the coordinate system described above and obtaining an azimuth and an elevation of the antenna will be described in detail as follows.

FIG. 6 is a flowchart for explaining a drive control method for a non-geostationary satellite antenna according to an embodiment of the present invention. FIG. 7 is a view showing a true angle of two axes, FIG.

Referring to FIG. 6, first, the geographical coordinate system (LLH _ANT ) of the antenna is obtained using latitude, longitude, altitude and GPS coordinates at which the antenna is installed (S101).

Next, the geo-coordinate system (LLH _ANT ) of the antenna is converted into the geo-coordinate system (ECEF _ANT ) (S102).

The equation for converting from LLH _ANT to ECEF _ANT is shown in Equation 1 below.

In other words, when the antenna's latitude, longitude, and altitude are converted to the above equation, it is converted to X _{ECEF_ANT} , Y _{ECEF_ANT} , and Z _{ECEF_ANT} of the antenna. In FIG. 3, the X, Y, and Z axes of the ECEF coordinate system are defined as follows.

Next, the satellite's geographical coordinate system (LLH _SAT ) is obtained using TLE (Two Line Element) information (S103).

Next, the conversion to the geocentric geographic coordinate system of the satellite _(SAT LLH) coordinate system (ECEF _SAT) (S104). The North American Aerospace Defense Command (TAM), which receives the TLE information, for example, TLE's origin time, average angular acceleration, average angular acceleration, orbit inclination angle, right ascension right ascension, eccentricity, NORAD) to calculate X _{ECEF _ SAT} , Y _{ECEF _ SAT} , and Z _{ECEF _ SAT} of the satellite using the SGP4 model.

The definitions of the physical and mathematical constants used in the SGP4 model are as follows.

sgp4_s.de2ra = 0.017453292519943295

sgp4_s.e6a = 0.000001

sgp4_s.pi = 3.1415926535897931

sgp4_s.pio2 = 1.57079633

sgp4_s.qo = 120.0

sgp4_s.so = 78.0

sgp4_s.tothrd = 0.66666667

sgp4_s.twopi = 6.2831853

sgp4_s.x3pio2 = 4.71238898

sgp4_s.xj2 = 0.001082616

sgp4_s.xj3 = -0.00000253381

sgp4_s.xj4 = -0.00000165597

sgp4_s.xke = 0.0743669161

sgp4_s.xkmper = 6378.137

sgp4_s.xmnpda = 1440.0

sgp4_s.ae = 1.0

sgp4_s.ck2 = 0.5 * sgp4_s.xj2 * (sgp4_s.ae * sgp4_s.ae)

sgp4_s.ck4 = 0.375 * sgp4_s.xj4 * (sgp4_s.ae * sgp4_s.ae * sgp4_s.ae * sgp4_s.ae)

temp = ((sgp4_s.qo - sgp4_s.so) * sgp4_s.ae / sgp4_s.xkmper)

sgp4_s.qoms2t = temp * temp * temp * temp

sgp4_s.s = sgp4_s.ae * (1 + sgp4_s.so / sgp4_s.xkmper)

Here, the parameters in the TLE file are defined as follows.

epoch: starting point

xndt2o: average angular acceleration

xndd6o: average angular acceleration

iexp: Ephemeris type

bstar: BSTAR

ibexp: Ephmeris number

xincl: Orbit inclination angle

xnodeo: Right ascension school

eo: eccentricity

omegao: perigee angle

xmo: the mean nearest point

xno: average acceleration

rev_n: Revolution numver at epoch

eo = eo * 0.0000001

xnodeo1 = xnodeo

omegao1 = omegao

xmo1 = xmo

xincl1 = xincl

xno1 = xno

xndt2o1 = xndt2o

xndd6o = xndd6o * 0.00001

bstar = bstar * 0.00001

xndd6o = xndd6o * Math.Pow (10, iexp)

xnodeo = xnodeo * sgp4_s.de2ra

omegao = omegao * sgp4_s.de2ra

xmo = xmo * sgp4_s.de2ra

xincl = xincl * sgp4_s.de2ra

temp = sgp4_s.twopi / sgp4_s.xmnpda / sgp4_s.xmnpda

xno = xno * temp * sgp4_s.xmnpda

xndt2o = xndt2o * temp

xndd6o = xndd6o * temp / sgp4_s.xmnpda

bstar = bstar * Math.Pow (10, ibexp) / sgp4_s.ae

tle.epoch = epoch

tle.xndt2o = xndt2o

tle.xndd6o = xndd6o

tle.iexp = iexp

tle.bstar = bstar

tle.ibexp = ibexp

tle.xincl = xincl

tle.xnodeo = xnodeo

tle.eo = eo

tle.omegao = omegao

tle.xmo = xmo

tle.xno = xno

tle.rev_n = rev_n

Next, it converts the ECEF _SAT and _ANT ECEF to ENU _ANT (S105). That is, the value of the ECEF coordinate system of the antenna and the satellite obtained in S101 to S104 process X _{ECEF _ SAT,} Y _{ECEF _ SAT,} Z _{ECEF_SAT} and X _{ECEF _} using _ANT, Y _{ECEF _ ANT,} Z _{ECEF _ ANT} at the ground station antenna ENU coordinate system.

The X _{ECEF _ SAT} , Y _{ECEF _ SAT} , and Z _{ECEF _ SAT} are the ECEF _SAT Coordinates and, _ECEF X _{_ ANT, ANT _ ECEF} Y, Z of the antenna _{ANT ECEF_ANT} is ECEF Coordinates. φr and λr are the latitude and longitude of the reference point (origin) of the ENU coordinate system, and the two-axis ENU coordinate values ENU _{E ,} ENU _N , and ENU _U are calculated by the conversion formula.

The conversion formula is shown in Equation 2 below.

The definition of the parameter in the above equation is as follows.

X _{ECEF _ SAT} : X of the ECEF coordinates of the satellite

Y _{ECEF _ SAT} : Y of the ECEF coordinates of the satellite

Z _{ECEF _ SAT} : Z of the ECEF coordinates of the satellite

X _{ECEF _ ANT:} the ECEF coordinates of the antenna X

Y _{ECEF _ ANT:} antenna Y coordinates in ECEF

Z _{ECEF _ ANT:} the ECEF coordinates of the antenna Z

ENU _E : E of the ENU coordinate

ENU _N : N of the ENU coordinate

ENU _U : U of the ENU coordinate

φ _r ,: the latitude of the reference point of the ENU coordinate system

λ _r : Longitude of the reference point of the ENU coordinate system

Also, a true angle of two axes can be obtained as shown in FIG. 7 using the ENU _ANT obtained in step S105 (S106). That is, the azimuth angle and the elevation angle in the two-axis coordinate system are obtained before obtaining the azimuth and elevation angles in the three-axis coordinate system, and the calculation can be omitted in the calculation on the three-axis algorithm as shown in FIG.

The azimuth and elevation from the ENU coordinate system obtained in the previous step are expressed by Equation (3).

The parameter definition in the above equation is as follows.

ENU _E : E of the ENU coordinate

ENU _N : N of the ENU coordinate

ENU _U : U of the ENU coordinate

R: Distance

Φ _{ANT _ TRUE} : True_Azimuth of the antenna

λ _{ANT _ TRUE:} antenna True_Elevation

Next, ENU _ANT is converted into BODY _ANT by applying Tilt and Train (S107). That is, it is a process of converting from ENU to an antenna co-ordinate system (BODY), and is an algorithm conversion step in a three-axis antenna using Tilt and Train.

The following is the conversion from the ENU coordinate system to the antenna co-ordinate system.

ENU _E , ENU _N , and ENU _U are the coordinate values of the 2-axis ENU, and calculate the following equation by taking the tilt and train into account.

Equation 4 below can be applied to the slope and train values depending on the hardware. For reference, the slope in this embodiment is -7 °, and the train is calculated by setting the az value at max el in the path.

The parameter definition in the above equation is as follows.

ENU _E : E of the ENU coordinate

ENU _N : N of the ENU coordinate

ENU _U : U of the ENU coordinate

BODY _E : E of the BODY coordinate

BODY _N : N of the BODY coordinate

BODY _U : U of the BODY coordinate

Next, the mount angle of the antenna is obtained using the body coordinate system as shown in FIG. 8 (S108). That is, the process of obtaining azimuth angle and elevation angle, which are the final control values of the three-axis algorithm, using the body coordinate system obtained in step S107.

The equation for obtaining the azimuth angle and elevation angle from the three-axis fuselage coordinate system is shown in Equation (5).

The parameter definition in the above equation is as follows.

BODY _E : E of the BODY coordinate

BODY _N : N of the BODY coordinate

BODY _U : U of the BODY coordinate

R: Distance

Φ _{ANT _ Mount:} antenna Mount_Azimuth

λ _{ANT _ Mount} : Mounting the antenna _Elevation

9 is a diagram illustrating a hardware configuration of a 3-axis antenna according to an embodiment of the present invention, in which a 3-axis antenna 1 model is designed using 3-D CAD software such as Solid Works.

Referring to FIG. 9, the azimuth angle and elevation angle are the same as the basic modeling of the conventional 2.4 m antenna, and a slope and a train axis are added to the lower end of the 2.4 m antenna. In this embodiment, the azimuth angle, elevation angle, and train axis can be changed, and the tilt axis is fixed at -7 °.

Three-dimensional modeling and implementation of the three-axis transformation algorithm The comparison conditions of the driving angle are as follows.

- The three-dimensional modeled antenna can input the train, azimuth angle, elevation angle.

- The train value inputs the train value generated from the virtual table track.

- The input values of the azimuth and elevation are the azimuth and elevation to which the 3-axis transformation algorithm is applied.

- When inputting the azimuth and elevation values using the 3-axis transformation algorithm, the 3D modeled antenna moves to the corresponding value position.

- The 2-axis azimuth and elevation angle are the angles looking at the satellite at the horizontal and vertical positions from the ground, so compare the azimuth and elevation of the entered 3-axis transformation algorithm.

Tables 1 and 2 below show the comparison between the three-dimensional modeling and the driving angles of the three-axis conversion algorithm implemented according to the present invention.

Max Elevation (38.584) 3-axis transformation algorithm 3D modeling Azimuth Elevation AZ_PED EL_PED Azimuth Elevation AZ_PED EL_PED 192.559 9.876 294.801 12.886 192.559 9.876 294.801 12.886 195.211 12.58 297.158 15.863 195.211 12.579 297.158 15.863 198.46 15.589 300.095 19.202 198.461 15.589 300.095 19.202 202.519 18.955 303.834 22.967 202.519 18.954 303.834 22.967 207.691 22.705 308.706 27.205 207.69 22.705 308.706 27.205 214.402 26.808 315.208 31.896 214.402 26.809 315.208 31.896 223.203 31.074 324.038 36.838 223.204 31.074 324.038 36.838 234.64 35.021 336.004 41.471 234.64 35.021 336.004 41.471 248.802 37.812 351.449 44.743 248.802 37.813 351.449 44.743 260.365 38.584 4.334 45.566 260.365 38.584 4.334 45.566 264.641 38.544 9.105 45.466 264.642 38.545 9.105 45.466 280.037 36.931 26.029 43.289 280.037 36.931 26.029 43.289 293.182 33.581 39.892 39.08 293.181 33.581 39.892 39.08 303.541 29.439 50.315 34.066 303.541 29.44 50.315 34.066 311.464 25.211 57.976 29.082 311.464 25.212 57.976 29.082 317.529 21.245 63.664 24.497 317.529 21.245 63.664 24.497 322.243 17.656 67.983 20.409 322.243 17.656 67.983 20.409 325.982 14.443 71.344 16.792 325.982 14.443 71.344 16.792 329.007 11.567 74.021 13.585 329.008 11.568 74.021 13.585 331.505 8.977 76.199 10.718 331.505 8.976 76.199 10.718 333.603 6.623 78.005 8.132 333.603 6.622 78.005 8.132 335.393 4.465 79.526 5.776 335.393 4.465 79.526 5.776 336.944 2.469 80.827 3.608 336.944 2.469 80.827 3.608

Max Elevation (63.20200) 3-axis transformation algorithm 3D modeling Azimuth Elevation AZ_PED EL_PED Azimuth Elevation AZ_PED EL_PED 2.042 174.569 0.719 100.966 2.042 174.569 0.719 100.966 4.106 175.223 2.689 101.862 4.105 175.223 2.689 101.862 6.359 175.987 4.836 102.889 6.359 175.987 4.836 102.889 8.851 176.89 7.203 104.082 8.851 176.89 7.203 104.082 11.651 177.981 9.854 105.499 11.651 177.981 9.854 105.499 14.851 179.327 12.873 107.217 14.85 179.326 12.873 107.217 18.58 181.036 16.377 109.363 18.58 181.036 16.377 109.363 23.019 183.288 20.527 112.136 23.019 183.288 20.527 112.136 28.416 186.392 25.537 115.876 28.416 186.391 25.537 115.876 35.076 190.943 31.657 121.205 35.076 190.943 31.657 121.205 43.258 198.183 39.051 129.317 43.258 198.183 39.051 129.317 61.073 235.043 54.379 164.537 61.073 235.043 54.379 164.537 63.226 260.179 56.261 185.195 63.226 260.178 56.261 185.195 62.668 271.381 55.935 194.361 62.668 271.381 55.935 194.361 55.832 300.461 50.74 220.224 55.832 300.46 50.74 220.224 46.337 316.214 42.773 236.498 46.337 316.213 42.773 236.498 37.668 324.864 35.119 246.282 37.668 324.865 35.119 246.282 30.531 330.138 28.651 252.534 30.531 330.138 28.651 252.534 24.758 333.657 23.343 256.825 24.758 333.657 23.343 256.825 20.038 336.173 18.963 259.951 20.038 336.172 18.963 259.951 16.101 338.067 15.286 262.343 16.101 338.068 15.286 262.343 12.747 339.553 12.138 264.244 12.747 339.553 12.138 264.244 9.831 340.757 9.39 265.804 9.831 340.757 9.39 265.804

We also compared the 3D modeling driving angle by changing the azimuth angle and elevation angle after locating the train at zero on its 7.3 m antenna. As shown in Table 3 below, the largest error is 0.029 degrees when the antenna itself is compared with the three-dimensional modeling driving angle.

Three-dimensional modeling and its own 7.3m antenna driving information comparison 7.3m drive angle 3D modeling error AZ EL AZ_PED EL_PED AZ EL AZ_PED EL_PED AZ EL 354.5 -6.997 0 0 354.5 -7 0 0 0 0.003 44.5 -4.51 49.8 0 44.511 -4.512 49.8 0 -0.011 0.002 94.5 1.224 100.102 0 94.528 1.225 100.102 0 -0.028 -0.001 144.5 6.068 150.205 0 144.52 6.071 150.205 0 -0.02 -0.003 194.5 6.579 199.858 0 194.495 6.582 199.858 0 0.005 -0.003 244.5 2.407 249.833 0 244.471 2.408 249.833 0 0.029 0 294.5 -3.51 300.173 0 294.487 -3.512 300.173 0 0.013 0.002 344.5 -6.892 350.061 0 344.488 -6.894 350.061 0 0.012 0.002 7.3m drive angle 3D modeling error AZ EL AZ_PED EL_PED AZ EL AZ_PED EL_PED AZ EL 354.5 -1.997 0 5 354.5 -2 0 5 0 0.003 44.5 0.51 50.247 5 44.488 0.508 50.247 5 0.012 0.002 94.5 6.26 100.7 5 94.52 6.26 100.7 5 -0.02 0 144.5 11.077 150.492 5 144.501 11.079 150.492 5 -0.001 -0.002 194.5 11.584 199.645 5 194.491 11.586 199.645 5 0.009 -0.002 244.5 7.435 249.298 5 244.514 7.436 249.298 5 -0.014 -0.001 294.5 1.517 299.651 5 294.497 1.515 299.651 5 0.003 0.002 344.5 -1.89 349.95 5 344.483 -1.893 349.95 5 0.017 0.003 7.3m drive angle 3D modeling error AZ EL AZ_PED EL_PED AZ EL AZ_PED EL_PED AZ EL 354.5 3 0 10 354.5 3 0 10 0 0 44.5 5.531 50.713 10 44.477 5.529 50.713 10 0.023 0.002 94.5 11.297 101.315 10 94.52 11.297 101.315 10 -0.02 0 144.5 16.087 150.818 10 144.516 16.089 150.818 10 -0.016 -0.002 194.5 16.589 199.421 10 194.479 16.591 199.421 10 0.021 -0.002 244.5 12.473 248.674 10 244.477 12.474 248.674 10 0.023 -1E-03 294.5 6.545 299.114 10 294.5 6.544 299.114 10 0 0.001 344.5 3.111 349.852 10 344.493 3.108 349.852 10 0.007 0.003 7.3m drive angle 3D modeling error AZ EL AZ_PED EL_PED AZ EL AZ_PED EL_PED AZ EL 354.5 8.003 0 15 354.5 0 0 15 0 0.003 44.5 10.559 51.25 15 44.521 10.557 51.25 15 -0.021 0.002 94.5 16.335 101.952 15 94.522 16.336 101.952 15 -0.022 -1E-03 144.5 21.095 151.105 15 144.482 21.097 151.105 15 0.018 -0.002 194.5 21.593 199.208 15 194.485 21.596 199.208 15 0.015 -0.003 244.5 17.503 248.111 15 244.519 17.504 248.111 15 -0.019 -0.001 294.5 11.575 298.551 15 294.495 11.574 298.551 15 0.005 0.001 344.5 8.112 349.738 15 344.49 8.109 349.738 15 0.01 0.003 7.3m drive angle 3D modeling error AZ EL AZ_PED EL_PED AZ EL AZ_PED EL_PED AZ EL 354.5 13.003 0 20 354.5 13 0 20 0 0.003 44.5 15.581 51.75 20 44.505 15.579 51.75 20 -0.005 0.002 94.5 21.374 102.602 20 94.507 21.374 102.602 20 -0.007 0 144.5 26.106 151.455 20 144.496 26.108 151.455 20 0.004 -0.002 194.5 26.596 199.008 20 194.516 26.599 199.008 20 -0.016 -0.003 244.5 22.542 247.461 20 244.504 22.542 247.461 20 -0.004 0 294.5 16.608 297.951 20 294.479 16.606 297.951 20 0.021 0.002 344.5 13.113 349.638 20 344.506 13.11 349.638 20 -0.006 0.003

According to the comparison between driving angles and satellite tracking results, the error between the 3D modeling and the 3-axis conversion algorithm in the driving angle comparisons was within 0.001 for both the azimuth and elevation angles, and the error between the 3D modeling and the 7.3m antenna itself was 0.029 , And the maximum elevation angle is 0.003, indicating that there is almost no error in the driving design of the conventional 7.3m antenna.

In addition, it was confirmed that the largest error was 0.029 as a result of comparing the three-dimensional driving angle while changing the azimuth angle and elevation angle after locating the train at zero at its own 7.3 m antenna.

In comparison of the driving angles, it is judged that the error between the 3-axis transformation algorithm, the 3-D modeling error and the 7.3m antenna itself is less than 0.03, but it is difficult to acquire information according to the accurate time when acquiring information Therefore, even if time compensation is performed, some error may occur.

Embodiments of the present invention include computer readable media including program instructions for performing various computer implemented operations. The computer-readable medium may include program instructions, local data files, local data structures, and the like, alone or in combination. The media may be those specially designed and constructed for the present invention or may be those known to those skilled in the computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floppy disks, and ROMs, And hardware devices specifically configured to store and execute the same program instructions. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, 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 similarities.

Accordingly, the scope of the present invention should be construed as being limited to the embodiments described, and it is intended that the scope of the present invention encompasses not only the following claims, but also equivalents thereto.

1: 3-axis antenna

Claims (9)

A method of driving a non-geostationary satellite antenna having three axes of azimuth, elevation, and tilt,
Obtaining a geographical coordinate system (LLH _ANT ) of the antenna using latitude, longitude, altitude and GPS coordinates at which the antenna is installed, and converting the LLH _ANT into a center coordinate system (ECEF _ANT ) of the antenna;
Obtaining LLH _SAT of the satellite using TLE (Two Line Element) information and converting the LLH _SAT into a satellite center coordinate system (ECEF _SAT ) of the satellite;
Converting the ECEF _ANT and the ECEF _SAT into a north-east coordinate system (ENU _ANT ) of an antenna;
Converting the ENU _ANT into an antenna body coordinate system (BODY _ANT );
And deriving an antenna installation angle using the BODY _ANT .
The method of claim 1, further comprising: obtaining a true angle of biaxiality using the ENU _ANT .
2. The method of claim 1, wherein the step of converting the LLH _ANT to an antenna center coordinate system (ECEF _ANT )
Wherein the non-geostationary satellite antenna is made up of the following formula (1).
[Equation 1]

In Equation (1)

Respectively.
The method of claim 1, wherein the step of converting the LLH _SAT into a satellite center coordinate system (ECEF _SAT )
TLE of gisanjeom time, the average angular acceleration, the average Angular acceleration, inclination, ascending node RA, eccentricity, perigee each, mean anomaly of each, by utilizing SGP4 model receives the at least one of the average acceleration satellite X _{ECEF _ SAT,} Y _{ECEF SAT _, _} Z _ECEF drive control method of a non-stop wiseongyong the antenna made of a process of calculating the _SAT according to claim.
2. The method of claim 1, wherein the step of converting the ECEF _ANT and the ECEF _SAT into an antenna north-east coordinate system (ENU _ANT )
Wherein the non-geostationary satellite antenna is made up of the following formula (2).
&Quot; (2) "

In Equation 2 X _{ECEF _ SAT} are X, Y _ECEF the ECEF coordinates of the satellite _{_ SAT} is the ECEF coordinates of the satellite Y, Z _{ECEF _ SAT} is the ECEF coordinates of the satellite Z, X _{ECEF _ ANT} is ECEF coordinates of the antenna the X, Y _{ECEF _ ANT} is the ECEF coordinates of the antenna Y, Z _{ECEF _ ANT} is of Z, ENU _E ECEF coordinates of the antenna E is the ENU coordinate, ENU is the _N of the ENU coordinate, UU is the _U of the ENU coordinate, φ _r is the latitude of the ENU coordinate system reference point, and λ _r is the hardness of the ENU coordinate system reference point.
The method of claim 1, wherein the step of converting the ENU _ANT into an antenna body coordinate system (BODY _ANT )
Wherein the non-geostationary-satellite antenna is made up of the following formula (3).
&Quot; (3) "

In Equation (3), ENU _E E of the ENU coordinate, ENU _N is the _N of the ENU coordinate, ENU _U U, BODY _E of the ENU coordinate E of BODY coordinate, BODY _N is _N of BODY coordinate, BODY _U Of the BODY coordinate,

Lt; / RTI >

Respectively.
2. The method of claim 1, wherein the step of deriving an antenna installation angle using the BODY _ANT
Wherein the non-geostationary-satellite antenna is made up of the following formula (4).
&Quot; (4) "

In Equation (4), BODY _E E of the BODY coordinate, BODY _N Are coordinates of the BODY N, _U is a BODY BODY coordinates U, R is the distance, Φ _{_ Mount ANT} is Mount_Azimuth, λ represents the Mount _Elevation _{ANT_Mount} antenna of each antenna.
3. The method according to claim 2, wherein the step of obtaining a true angle of two axes using the ENU _ANT
Wherein the non-geostationary-satellite antenna is made up of the following formula (5).
&Quot; (5) "

In Equation (5), ENU _E E, ENU _N of the ENU coordinate Of the ENU coordinate N, ENU _U Is the ENU coordinate U, R is the distance, Φ _{_ ANT} is _TRUE True_Azimuth, λ _{_ TRUE} antenna _ANT denotes a True_Elevation of the antenna.
A program recording medium on which a program for executing a drive control method for a non-geostationary satellite antenna according to any one of claims 1 to 8 is recorded.

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