阅读说明：本技术 地面测站天线对卫星的指向导引系统 (Pointing guidance system of ground survey station antenna to satellite ) 是由 辛阁霖 易灵 苏小明 许榆川 陆启省 李绿萍 凌惠祥 于 2020-03-19 设计创作，主要内容包括：本发明提供一种地面测站天线对卫星的指向导引系统,包括：惯性系卫星位置模块：输入目标时刻t<Sub>1</Sub>的星历信息,输出t<Sub>1</Sub>时刻卫星在惯性系下的位置R<Sub>wECI</Sub>；地固系卫星位置模块：输入目标时刻t<Sub>1</Sub>和所述卫星在惯性系下的位置R<Sub>wECI</Sub>,输出t<Sub>1</Sub>时刻卫星在地固系下的位置R<Sub>wECF</Sub>。本发明不依赖于仿真软件或过多假设内容,考虑卫星实际运行情况计算地面测站天线对卫星的指向,有效解决了地面站接收天线对卫星的指向控制问题,而且达到了比较高的指向精度。(The invention provides a pointing guidance system of a ground survey station antenna for a satellite, which comprises: inertial system satellite position module: inputting a target time t 1 Outputs t from the ephemeris information 1 Position R of time satellite under inertial system wECI (ii) a Geostationary satellite position module: inputting a target time t 1 And the position R of said satellite in the inertial system wECI Output t 1 Position R of time satellite under earth's fixation wECF . The invention does not depend on simulation software or excessive assumed contents, considers the actual running condition of the satellite to calculate the direction of the ground station antenna to the satellite, effectively solves the problem of controlling the direction of the ground station receiving antenna to the satellite, and achieves higher direction accuracy.)

1. A system for directing a satellite by an antenna of a ground station, comprising:

inertial system satellite position module:inputting a target time t₁Outputs t from the ephemeris information₁Position R of time satellite under inertial system_wECI；

Geostationary satellite position module: inputting a target time t₁And the position R of said satellite in the inertial system_wECIOutput t₁Position R of time satellite under earth's fixation_wECF；

The antenna position module of the ground fixed system survey station: inputting longitude and latitude and elevation of the ground station antenna, and outputting the position R of the ground station antenna under a ground fixation system_tECF；

A station-based satellite position module: inputting the t₁Position R of time satellite under earth's fixation_wECFAnd the position R of the ground survey station antenna under the ground fixing system_tECFOutput t₁Position R of time satellite under the system of the center of the station_wCT；

The survey station antenna pointing guidance angle module: inputting the position of the satellite under the station center system and outputting t₁The antenna pointing guidance angle of the ground survey station at the moment: high and low angleHorizontal angle psi. The antenna pointing guiding process is completed through the two pointing guiding angles.

2. The ground station antenna-to-satellite pointing guidance system of claim 1, wherein the inertial system satellite position module:

inputting a target time t₁Includes: the device comprises a track semi-major axis a, a track eccentricity e, a track inclination angle i, a rising intersection declination omega, an argument omega of a near place and an average and near point angle M;

calculating t₁Position R of time satellite under inertial system_wECI：

R_wECI＝Q*r_p

Wherein the content of the first and second substances,

the rotation matrix Q is described in the order of 3-1-3 rotations:

vector r_p：

Wherein M is₁True proximal angle:

3. the ground station antenna-to-satellite pointing guidance system of claim 1, wherein the geostationary satellite position module:

according to a given target time t₁Calculating a second count value t of epoch J2000.0 to a predetermined target time_cInputting t₁Year, month, day, hour, minute, second of the moment, calculate julian day JD:

wherein the content of the first and second substances,

floor () is a round-down operation;

calculating a second count value t from epoch J2000.0 to a given target time based on the julian day JD_c：

t_c＝(JD-2455197.5)×86400+315547200

According to the epoch J2000.0 obtained by calculation to the second counting value t of the given target time_cCalculating the rotation matrix ER, nutation matrix NR and precision matrix PR of the earth, and calculating the transformation matrix M from the inertial system to the earth-fixed system_ECI2ECF：

M_ECI2ECF＝ER*NR*PR

According to the t₁Position R of time satellite under inertial system_wECIAnd the calculated transformation matrix M from the inertial system to the earth-fixed system_ECI2ECFCalculating t₁Position R of time satellite under earth's fixation_wECF：

R_wECF＝M_ECI2ECF*R_wECI。

4. The ground station antenna-to-satellite pointing guidance system of claim 1, wherein the ground station antenna position module:

inputting longitude lon, latitude lat and elevation h of an antenna of the ground station;

computing coordinate components G1, G2:

wherein the content of the first and second substances,

re represents the Earth's equatorial radius;

f is the geometric oblateness of the earth ellipsoid, and f is 1/298.257;

calculating the position R of the ground survey station antenna under the ground fixing system_tECF：

5. The system of claim 1 wherein the station-based satellite position module:

under the system of the station center, a conversion matrix M from the earth fixation system to the system of the station center is calculated_ECF2CTDescribed as one rotation about the Z-axis of the earth fixation system and one rotation about the X-axis of the earth fixation system:

M_ECF2CT＝R_x(90°-lat)R_z(90°+lon)

wherein the content of the first and second substances,

lon is the geographical longitude of the antenna of the ground survey station;

lat is the geographical latitude of the antenna of the ground station;

according to the t₁Position R of time satellite under earth's fixation_wECFPosition R of the ground station antenna under the ground anchor_tECFAnd a transformation matrix M tied to the site-centric system_ECF2CTTranslating the origin of coordinates from the geocentric to the antenna of the ground survey station, and calculating t₁Position R of time satellite under the system of the center of the station_wCT：

R_wCT＝M_ECF2CT*(R_wECF-R_tECF) 。

6. The ground station antenna-to-satellite pointing guidance system of claim 1, wherein the station antenna pointing guidance angle module:

the high and low angles and the horizontal angle are defined under the station center systemTo point to a vector R_wCTAnd O_CTX_CTY_CTAngle of plane, X_CTRepresenting the x-axis, Y-axis of the antenna coordinate system of the station_CTRepresenting the y-axis of the antenna coordinate system of the measuring station, defining R_wCTVector sum of O_CTZ_CTThe included angle is less than 90 degrees and is positive; the horizontal angle psi being the director vector R_wCTAt O_CTX_CTY_CTProjection of plane and O_CTX_CTAngle of axis, defined around O_CTZ_CTShaft driven O_CTX_CTShaft clockwise steering pointing vector R_wCTAt O_CTX_CTY_CTThe projection of the surface is positive, and the antenna pointing angle is determined according to this definition. Assuming that the position of the ground survey station is at the origin of the station center system, the antenna pointing vector of the survey station is at the station center systemProjection of lower is R_wCTRecord R_wCTComprises the following steps:

wherein the content of the first and second substances,

x_CT、y_CT、z_CTrespectively representing the x, y and z three-axis coordinate components of the projection of the antenna pointing vector of the observation station on the station center system;

calculating elevation angle of antenna pointing guiding angleThe horizontal angle ψ is:

and according to x_CT、y_CT、z_CTPositive and negative of (2), angle of elevationDividing the horizontal angle psi into corresponding angle ranges to complete the antenna pointing guidance process:

if z is_CTIf < 0, the high and low angles will be formedDivision into ranges

If z is_CTMore than or equal to 0, the height and angle will be changedDivision into ranges

If x_CT≥0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTIf < 0, the horizontal angle psi is divided into ranges

If x_CT≥0,y_CTIf < 0, the horizontal angle psi is divided into ranges

Technical Field

The invention relates to the field of satellite attitude and orbit control, in particular to a pointing guidance system of a ground survey station antenna for a satellite.

Background

The radar plays a very important role in the scientific and technological construction of China, and along with the requirements of detecting and controlling an outer space target, the practical radar is rapidly developed and is applied to a plurality of important fields such as guidance, beyond-the-horizon detection and the like at present. With the development of the space detection technology, higher and higher requirements are put forward on the tracking and searching capabilities of a radar antenna, because a satellite signal is weak and has strong directivity, in order to capture a communication signal on a moving satellite, the deviation between the attitude of the antenna and the position of the satellite must be adjusted in real time to meet the communication requirement, because the signal-to-noise ratio of link transmission information is reduced due to the satellite-to-ground directional deviation, and if the signal-to-noise ratio exceeds the maximum station tolerance, the signal loss phenomenon can even occur. This requires that the radar antenna must adjust the pointing direction according to the command to track the moving target in real time. Therefore, the dynamic precision of the radar antenna pointing process becomes one of the important indexes of the antenna system function, and the design of the pointing calculation method with high pointing precision has general practical significance.

The method is characterized in that the pointing guidance of the ground survey station antenna to the satellite is mainly to calculate the antenna pointing guidance angle at a target moment according to the orbit information and the time information of the satellite and the position information of the ground survey station antenna, and realize the accurate pointing to the satellite at the target moment through the antenna pointing control.

The existing research on satellite-ground pointing algorithms in China mostly focuses on the optimization design of pointing of a satellite to a ground survey station under the condition that the position of the ground survey station is fixed, and the research on the pointing guidance of a ground survey station antenna to the satellite is less. Under the condition that the ground survey station is movable, under the condition that the geographical longitude, latitude and elevation of the ground survey station are known and the track information of the on-orbit aircraft is tracked, the pointing guidance of the aircraft is automatically finished, and the pointing guidance angle of the antenna is calculated in real time. Aiming at the actual situation, the invention provides a ground station real-time positioning method with higher precision for a ground station antenna, and the method can realize the autonomous pointing guidance of the ground station antenna to a satellite.

The patent "design method of deep space probe antenna pointing" (patent number: CN104369877A) describes a method of pointing a deep space probe antenna to the ground center, which is used to realize the deep space probe antenna to the ground center orientation. The patent is directed to the orientation of the antenna to the geocenter and not to the given position of the earth surface, and the pointing vector of the detector antenna to the geocenter is directly given, and no algorithm for calculating the satellite position through the orbit parameters exists. The method is different from the method in that a method for calculating the satellite pointing direction of the ground station aiming at the given position of the earth surface is designed, the positioning calculation of the ground station is completed, and a calculation process for calculating the ground station-satellite pointing vector through the satellite orbit parameters at the given moment is designed.

The patent "simulation analysis method of pointing angle of data transmission antenna" (patent number: CN105184002A) introduces a method for calculating pointing direction of satellite-borne data transmission antenna to ground station, which uses existing satellite orbit simulation software STK to perform simulation solution on actual position of satellite and calculates two-dimensional pointing angle of data transmission antenna. The disadvantage of the patent is that the satellite position calculation depends on the satellite orbit simulation software STK, no specific calculation process is needed, the description of the coordinate system conversion is simple, and no algorithm of a conversion matrix is given. The invention has the advantages of providing a method for calculating the actual position of the satellite according to the orbit parameters of the satellite at the appointed time without depending on STK software and designing a set of detailed calculation flow of a related coordinate system conversion matrix.

The patent "a method for controlling the pointing direction of a dual-axis antenna to the ground around a moon satellite" (patent number: CN101204994A) describes a method for calculating the pointing direction of a satellite to the earth center around a moon satellite, which estimates the position of the satellite according to ephemeris data on the ground, calculates the visible area of the satellite to the earth, and calculates the pointing angle of the dual-axis antenna. The patent is directed to the geocenter, does not orient the surface location, and is mainly calculated in combination with a moon-related coordinate system. The invention is different from the method in that the calculation is mainly combined with the earth and the earth surface position related coordinate system to complete the position calculation of the ground survey station antenna and the directional calculation of the ground survey station antenna to the satellite, and the definition and the calculation method of the antenna directional angle are different.

The literature, "pointing algorithm and simulation of satellite sharp beam antenna" (see "Chinese space science and technology", 2008, 2 nd), introduces an algorithm for pointing a satellite-borne sharp beam antenna to an earth surface target point, and the method has the disadvantages that many influence factors are ignored in the process of converting a coordinate system, influences such as time difference and nutation are not considered, and the pointing accuracy is low. The invention deduces formulas on the influence caused by the possible error factors, so that the coordinate system conversion process is more accurate.

Disclosure of Invention

In view of the defects in the prior art, the invention aims to provide a pointing guidance system of a ground station antenna to a satellite.

The invention provides a system for guiding the direction of an antenna of a ground station to a satellite, which comprises:

inertial system satellite position module: inputting a target time t₁Outputs t from the ephemeris information₁Position R of time satellite under inertial system_wECI；

Geostationary satellite position module: inputting a target time t₁And the position R of said satellite in the inertial system_wECIOutput t₁Position R of time satellite under earth's fixation_wECF；

The antenna position module of the ground fixed system survey station: inputting longitude and latitude and elevation of the ground station antenna, and outputting the position R of the ground station antenna under a ground fixation system_tECF；

A station-based satellite position module: inputting the t₁Position R of time satellite under earth's fixation_wECFAnd the position R of the ground survey station antenna under the ground fixing system_tECFOutput t₁Position R of time satellite under the system of the center of the station_wCT；

The survey station antenna pointing guidance angle module: inputting the position of the satellite under the station center system and outputting t₁Antenna finger of time ground survey stationThe direction guiding angle is as follows: high and low angleHorizontal angle psi. The antenna pointing guiding process is completed through the two pointing guiding angles.

Preferably, the inertial system satellite position module:

inputting a target time t₁Includes: the device comprises a track semi-major axis a, a track eccentricity e, a track inclination angle i, a rising intersection declination omega, an argument omega of a near place and an average and near point angle M;

calculating t₁Position R of time satellite under inertial system_wECI：

R_wECI＝Q*r_p

Wherein the content of the first and second substances,

the rotation matrix Q is described in the order of 3-1-3 rotations:

vector r_p：

Wherein M is₁True proximal angle:

preferably, the geo-stationary satellite position module:

according to a given target time t₁Calculating a second count value t of epoch J2000.0 to a predetermined target time_cInputting t₁Year, month, day, hour, minute, second of the moment, calculate julian day JD:

wherein the content of the first and second substances,

floor () is a round-down operation;

calculating a second count value t from epoch J2000.0 to a given target time based on the julian day JD_c：

t_c＝(JD-2455197.5)×86400+315547200

According to the epoch J2000.0 obtained by calculation to the second counting value t of the given target time_cCalculating the rotation matrix ER, nutation matrix NR and precision matrix PR of the earth, and calculating the transformation matrix M from the inertial system to the earth-fixed system_ECI2ECF：

M_ECI2ECF＝ER*NR*PR

According to the t₁Position R of time satellite under inertial system_wECIAnd the calculated transformation matrix M from the inertial system to the earth-fixed system_ECI2ECFCalculating t₁Position R of time satellite under earth's fixation_wECF：

R_wECF＝M_ECI2ECF*R_wECI

Preferably, the geostationary survey station antenna position module:

inputting longitude lon, latitude lat and elevation h of an antenna of the ground station;

computing coordinate components G1, G2:

wherein the content of the first and second substances,

re represents the Earth's equatorial radius;

f is the geometric oblateness of the earth ellipsoid, and f is 1/298.257;

calculating the position R of the ground survey station antenna under the ground fixing system_tECF：

Preferably, the station-centric satellite position module:

under the system of the station center, a conversion matrix M from the earth fixation system to the system of the station center is calculated_ECF2CTDescribed as one rotation about the Z-axis of the earth fixation system and one rotation about the X-axis of the earth fixation system:

M_ECF2CT＝R_x(90°-lat)R_z(90°+lon)

wherein the content of the first and second substances,

lon is the geographical longitude of the antenna of the ground survey station;

lat is the geographical latitude of the antenna of the ground station;

according to the t₁Position R of time satellite under earth's fixation_wECFPosition R of the ground station antenna under the ground anchor_tECFAnd a transformation matrix M tied to the site-centric system_ECF2CTTranslating the origin of coordinates from the geocentric to the antenna of the ground survey station, and calculating t₁Position R of time satellite under the system of the center of the station_wCT：

R_wCT＝M_ECF2CT*(R_wECF-R_tECF)

Preferably, the station antenna points to a steering angle module:

the high and low angles and the horizontal angle are defined under the station center systemTo point to a vector R_wCTAnd O_CTX_CTY_CTAngle of plane, X_CTRepresenting the x-axis, Y-axis of the antenna coordinate system of the station_CTRepresenting the y-axis of the antenna coordinate system of the measuring station, defining R_wCTVector sum of O_CTZ_CTThe included angle is less than 90 degrees and is positive; the horizontal angle psi being the director vector R_wCTAt O_CTX_CTY_CTProjection of plane and O_CTX_CTClamp for shaftAngle, defined around O_CTZ_CTShaft driven O_CTX_CTShaft clockwise steering pointing vector R_wCTAt O_CTX_CTY_CTThe projection of the surface is positive, and the antenna pointing angle is determined according to this definition. Assuming that the position of the ground survey station is located at the origin of the station center system, the projection of the antenna pointing vector of the survey station under the station center system is R_wCTRecord R_wCTComprises the following steps:

wherein the content of the first and second substances,

x_CT、y_CT、z_CTrespectively representing the x, y and z three-axis coordinate components of the projection of the antenna pointing vector of the observation station on the station center system;

calculating elevation angle of antenna pointing guiding angleThe horizontal angle ψ is:

and according to x_CT、y_CT、z_CTPositive and negative of (2), angle of elevationDividing the horizontal angle psi into corresponding angle ranges to complete the antenna pointing guidance process:

if z is_CTIf < 0, the high and low angles will be formedDivision into ranges

If z is_CTMore than or equal to 0, the height and angle will be changedDivision into ranges

If x_CT≥0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTIf < 0, the horizontal angle psi is divided into ranges

If x_CT≥0,y_CTIf < 0, the horizontal angle psi is divided into ranges

Compared with the prior art, the invention has the following beneficial effects:

the invention does not depend on simulation software or excessive assumed contents, considers the actual running condition of the satellite to calculate the direction of the ground station antenna to the satellite, effectively solves the problem of controlling the direction of the ground station receiving antenna to the satellite, and achieves higher direction accuracy.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

fig. 1 is a schematic diagram illustrating a process of calculating a satellite pointing guiding angle by a ground station antenna.

Fig. 2 is a schematic diagram of the direction guidance of the ground station antenna to the satellite.

FIG. 3 shows a standing system O_CTX_CTY_CTZ_CTSchematic representation.

FIG. 4 shows the elevation angle of the standing heart systemAnd horizontal angle psi.

FIG. 5 is a schematic diagram of a variation curve of satellite positions under the inertial system.

FIG. 6 is a diagram illustrating a variation curve of the position of a satellite in the Earth's fixation system.

Fig. 7 is a schematic diagram of a projection variation curve of the pointing vector of the station antenna to the satellite under the station center system.

Fig. 8 is a schematic diagram of a variation curve of the pointing angle of the antenna of the survey station.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The invention provides a system for guiding the direction of an antenna of a ground station to a satellite, which comprises:

inertial system satellite position module: inputting a target time t₁Outputs t from the ephemeris information₁Position R of time satellite under inertial system_wECI；

Geostationary satellite position module: inputting a target time t₁And the position R of said satellite in the inertial system_wECIOutput t₁Position R of time satellite under earth's fixation_wECF；

The antenna position module of the ground fixed system survey station: inputting longitude and latitude and elevation of the ground station antenna, and outputting the position R of the ground station antenna under a ground fixation system_tECF；

A station-based satellite position module: input stationT is described₁Position R of time satellite under earth's fixation_wECFAnd the position R of the ground survey station antenna under the ground fixing system_tECFOutput t₁Position R of time satellite under the system of the center of the station_wCT；

The survey station antenna pointing guidance angle module: inputting the position of the satellite under the station center system and outputting t₁The antenna pointing guidance angle of the ground survey station at the moment: high and low angleHorizontal angle psi. The antenna pointing guiding process is completed through the two pointing guiding angles.

Specifically, the inertial system satellite position module:

inputting a target time t₁Includes: the device comprises a track semi-major axis a, a track eccentricity e, a track inclination angle i, a rising intersection declination omega, an argument omega of a near place and an average and near point angle M;

calculating t₁Position R of time satellite under inertial system_wECI：

R_wECI＝Q*r_p

Wherein the content of the first and second substances,

the rotation matrix Q is described in the order of 3-1-3 rotations:

vector r_p：

Wherein M is₁True proximal angle:

specifically, the geo-stationary satellite position module:

according to a given target time t₁Calculating epoch J2000.0 to a given targetSecond counting value t of the moment_cInputting t₁Year, month, day, hour, minute, second of the moment, calculate julian day JD:

wherein the content of the first and second substances,

floor () is a round-down operation;

calculating a second count value t from epoch J2000.0 to a given target time based on the julian day JD_c：

t_c＝(JD-2455197.5)×86400+315547200

According to the epoch J2000.0 obtained by calculation to the second counting value t of the given target time_cCalculating the rotation matrix ER, nutation matrix NR and precision matrix PR of the earth, and calculating the transformation matrix M from the inertial system to the earth-fixed system_ECI2ECF：

M_ECI2ECF＝ER*NR*PR

According to the t₁Position R of time satellite under inertial system_wECIAnd the calculated transformation matrix M from the inertial system to the earth-fixed system_ECI2ECFCalculating t₁Position R of time satellite under earth's fixation_wECF：

R_wECF＝M_ECI2ECF*R_wECI

Specifically, the earth-fixed-system survey station antenna position module:

inputting longitude lon, latitude lat and elevation h of an antenna of the ground station;

computing coordinate components G1, G2:

wherein the content of the first and second substances,

re represents the Earth's equatorial radius;

f is the geometric oblateness of the earth ellipsoid, and f is 1/298.257;

calculating the position R of the ground survey station antenna under the ground fixing system_tECF：

Specifically, the station-based satellite position module:

under the system of the station center, a conversion matrix M from the earth fixation system to the system of the station center is calculated_ECF2CTDescribed as one rotation about the Z-axis of the earth fixation system and one rotation about the X-axis of the earth fixation system:

M_ECF2CT＝R_x(90°-lat)R_z(90°+lon)

wherein the content of the first and second substances,

lon is the geographical longitude of the antenna of the ground survey station;

lat is the geographical latitude of the antenna of the ground station;

according to the t₁Position R of time satellite under earth's fixation_wECFPosition R of the ground station antenna under the ground anchor_tECFAnd a transformation matrix M tied to the site-centric system_ECF2CTTranslating the origin of coordinates from the geocentric to the antenna of the ground survey station, and calculating t₁Position R of time satellite under the system of the center of the station_wCT：

R_wCT＝M_ECF2CT*(R_wECF-R_tECF)

Specifically, the station antenna points to a steering angle module:

the high and low angles and the horizontal angle are defined under the station center systemTo point to a vector R_wCTAnd O_CTX_CTY_CTAngle of plane, X_CTRepresenting the x-axis, Y-axis of the antenna coordinate system of the station_CTRepresenting the y-axis of the antenna coordinate system of the measuring station, defining R_wCTVector sum of O_CTZ_CTThe included angle is less than 90 degrees and is positive; the horizontal angle psi being the director vector R_wCTAt O_CTX_CTY_CTProjection of plane and O_CTX_CTAngle of axis, defined around O_CTZ_CTShaft driven O_CTX_CTShaft clockwise steering pointing vector R_wCTAt O_CTX_CTY_CTThe projection of the surface is positive, and the antenna pointing angle is determined according to this definition. Assuming that the position of the ground survey station is located at the origin of the station center system, the projection of the antenna pointing vector of the survey station under the station center system is R_wCTRecord R_wCTComprises the following steps:

wherein the content of the first and second substances,

x_CT、y_CT、z_CTrespectively representing the x, y and z three-axis coordinate components of the projection of the antenna pointing vector of the observation station on the station center system;

calculating elevation angle of antenna pointing guiding angleThe horizontal angle ψ is:

and according to x_CT、y_CT、z_CTPositive and negative of (2), angle of elevationDividing the horizontal angle psi into corresponding angle ranges to complete the antenna pointing guidance process:

if z is_CTIf < 0, the high and low angles will be formedDivision into ranges

If z is_CTMore than or equal to 0, the height and angle will be changedDivision into ranges

If x_CT≥0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTThe horizontal angle psi is divided into ranges

If x_CT＜0,y_CTIf < 0, the horizontal angle psi is divided into ranges

If x_CT≥0,y_CTIf < 0, the horizontal angle psi is divided into ranges

The present invention will be described more specifically below with reference to preferred examples.

Preferred example 1:

the technical problem to be solved by the invention is as follows: the system is characterized in that satellite ephemeris data of a given target moment and geographical position information of an antenna of the ground measurement station are converted into an antenna pointing guide angle under a station center system through satellite orbit correlation calculation and conversion calculation of a plurality of correlation coordinate systems, and finally the antenna pointing guide angle is converted into an antenna pointing guide angle under the station center system so as to complete the process of pointing guide of the antenna of the ground measurement station to the satellite.

The invention combines a practical engineering situation: under the condition that the ground survey station is movable, under the condition that the geographical longitude, latitude and elevation of the ground survey station are known and the track information of the on-orbit aircraft is tracked, the pointing tracking of the aircraft is automatically completed, and the antenna pointing guiding angle is calculated in real time. The ground measurement station real-time positioning method is used for a ground measurement station antenna with high precision, and the ground measurement station antenna can guide the satellite in an autonomous pointing mode.

The pointing guidance system of the ground survey station antenna for the satellite calculates the position of the satellite in real time through satellite ephemeris information, considers influence factors of a coordinate system conversion relation comprehensively, has high calculation precision, provides the pointing guidance angle definition suitable for the ground survey station antenna, and effectively meets the requirement of the ground survey station antenna for real-time pointing guidance of the satellite.

The technical solution of the invention comprises the following steps:

(1) inertial system satellite position module: according to a given target time (UTC time) t₁Computing t from ephemeris information of₁Position R of time satellite under inertial system_wECIThe method comprises the following steps:

inputting a target time t₁Includes: the track comprises a semi-major axis a of the track, an eccentricity e of the track, a track inclination angle i, a rising intersection declination omega, an amplitude angle omega at a near place and an average angle M at a near point. Calculating t₁Position R of time satellite under inertial system_wECI：

R_wECI＝Q*r_p

Wherein the rotation matrix Q is described in a 3-1-3 rotation order:

vector r_p：

Wherein M is₁True proximal angle:

(2) geostationary satellite position module: according to a given target time t₁And the position R of the satellite calculated in the step (1) under the inertial system_wECICalculating t₁Position R of time satellite under earth's fixation_wECFThe method comprises the following steps:

(2.1) according to a given target time t₁Calculating a second counting value t from epoch J2000.0 (1/12/2000) to a predetermined target time_c；

(2.2) calculating a second counting value t from epoch J2000.0 (1 month, 1 day, 12 hours in 2000) to a given target time according to the step (2.1)_cAnd calculating a terrestrial rotation matrix ER, a nutation matrix NR and a time offset matrix PR, wherein the term is not considered in the invention because polar shift has little influence on the calculation of the conversion matrix. Calculating a transformation matrix M from an inertial system to a ground-based system_ECI2ECF：

M_ECI2ECF＝ER*NR*PR

(2.3) t calculated according to the step (1)₁Position R of time satellite under inertial system_wECIAnd the transformation matrix M of the inertial system to the earth-fixed system calculated in the step (2.2)_ECI2ECFCalculating t₁Position R of time satellite under earth's fixation_wECF：

R_wECF＝M_ECI2ECF*R_wECI

(3) The antenna position module of the ground fixed system survey station: according to the longitude, latitude and elevation of the given ground measurement station antenna, the position R of the ground measurement station antenna under the ground fixation system is calculated_tECFThe method comprises the following steps:

and inputting longitude lon, latitude lat and elevation h of the antenna of the ground station.

Computing coordinate components G1, G2:

wherein f is the geometric oblateness of the earth ellipsoid, and f is 1/298.257.

Calculating the position R of the ground survey station antenna under the ground fixing system_tECF：

(4) A station-based satellite position module: t calculated according to the step (2)₁Position R of time satellite under earth's fixation_wECFAnd the position R of the ground survey station antenna calculated in the step (3) under the ground system_tECFCalculating t₁Position R of time satellite under the system of the center of the station_wCTThe method comprises the following steps:

(4.1) under the station center system, calculating a conversion matrix M from the earth fixed system to the station center system_ECF2CTDescribed as one rotation about the Z-axis of the earth fixation system and one rotation about the X-axis of the earth fixation system:

M_ECF2CT＝R_x(90°-lat)R_z(90°+lon)

wherein lon is the geographic longitude of the antenna of the ground survey station; lat is the geographic latitude of the ground station antenna.

(4.2) t calculated according to the step (2)₁Position R of time satellite under earth's fixation_wECFThe position of the ground survey station antenna calculated in the step (3) under the ground fixation systemR_tECFThe conversion matrix M from the earth fixation system to the station center system calculated in the step (4.1)_ECF2CTTranslating the origin of coordinates from the geocentric to the antenna of the ground survey station, and calculating t₁Position R of time satellite under the system of the center of the station_wCT：

R_wCT＝M_ECF2CT*(R_wECF-R_tECF)

(5) The survey station antenna pointing guidance angle module: calculating t according to the position of the satellite under the station center system calculated in the step (4)₁The antenna pointing guide angle of the ground survey station at the moment: high and low angleHorizontal angle ψ by the following method:

the high and low angles and the horizontal angle are defined under the station center systemTo point to a vector R_wCTAnd O_CTX_CTY_CTAngle of plane, define R_wCTVector sum of O_CTZ_CTThe included angle is less than 90 degrees and is positive; the horizontal angle psi being the director vector R_wCTAt O_CTX_CTY_CTProjection of plane and O_CTX_CTAngle of axis, defined around O_CTZ_CTShaft driven O_CTX_CTShaft clockwise steering pointing vector R_wCTAt O_CTX_CTY_CTThe projection of the surface is positive, and the antenna pointing angle is determined from this definition, as shown in fig. 4. Assuming that the position of the ground survey station is located at the origin of the station center system, the projection of the antenna pointing vector of the survey station under the station center system is R_wCTRecord R_wCTComprises the following steps:

calculating elevation angle of antenna pointing guiding angleThe horizontal angle ψ is:

and according to x_CT、y_CT、z_CTPositive and negative of (2), angle of elevationDividing the horizontal angle psi into corresponding angle ranges to complete the antenna pointing guidance process:

preferred example 2:

the coordinate system required by the invention is as follows: the inertial system is a J2000.0 inertial coordinate system, and the earth fixation system is a WGS-84 coordinate system. The definition of the station center system is given below.

Standing heart system O_CTX_CTY_CTZ_CT

The center of the station is defined as the origin O_CTIs the ground antenna origin, the basic plane O_CTX_CTY_CTThe surface is a local horizontal surface, O_CTX_CTPointing to true north, O, along the meridian of the local area_CTZ_CTVertical base plane pointing to zenith, O_CTY_CTDetermined by the right hand rule, as shown in FIG. 3.

The calculation process of the present invention is detailed below:

the simulation of the algorithm was verified by using MAT L AB, the earth-related parameters and the station center are set as described above, and the ephemeris data of a certain type of satellite at UTC time 2018, 12, 3, 5 and 30 minutes are as follows:

the satellite pointing tracking is carried out from 5 hours and 30 minutes in 12 months, 3 days and 5 days in 2018 of UTC time, the simulation step length is 1s, the antenna pointing guiding angles (high and low angles and horizontal angles) are continuously simulated for 30 minutes, and satellite ephemeris data of every 1s serving as input are obtained through STK simulation.

(1) Inertial system satellite position module: according to a given target time (UTC time) t₁Computing t from ephemeris information of₁Position R of time satellite under inertial system_wECI. The specific calculation process is as follows:

according to t₁Includes: the track comprises a semi-major axis a of the track, an eccentricity e of the track, a track inclination angle i, a rising intersection declination omega, an amplitude angle omega at a near place and an average angle M at a near point. Calculating t₁Position R of time satellite under inertial system_wECIThe obtained position variation curve of the satellite under the inertial system is shown in fig. 5:

R_wECI＝Q*r_p

wherein the rotation matrix Q is described in a 3-1-3 rotation order:

vector r_p：

Wherein M is₁True proximal angle:

(2) geostationary satellite position module: according to a given target time t₁And the position R of the satellite calculated in the step (1) under the inertial system_wECICalculating t₁Position R of time satellite under earth's fixation_wECF. The method comprises the following specific steps:

(2.1) input of t₁Year (year), month (month), day (day), hour (hour), minute (min), and second (sec) of time (UTC time), julian day JD is calculated:

wherein floor () is a round-down operation.

Calculating a second counting value t from epoch J2000.0 (1 month, 1 day, 12 hours in 2000) to a given target time according to the julian day JD_c：

t_c＝(JD-2455197.5)×86400+315547200

(2.2) calculating a second counting value t from epoch J2000.0 (1 month, 1 day, 12 hours in 2000) to a given target time according to the step (2.1)_cAnd calculating a terrestrial rotation matrix ER, a nutation matrix NR and a precision matrix PR.

The specific calculation method is explained below:

calculating a yellow meridian nutation delta psi, a yellow-red intersection angle and an intersection angle nutation delta:

wherein, T_2kRelative epoch J2000.0 (1 month, 1 day, 12 of 2000):

the earth rotation matrix ER calculation method comprises the following steps:

calculating the declination nutation delta mu:

Δμ＝Δψ*cos

calculating greenNizhiping constancy

Calculating greenwich mean time S_G：

Calculating an earth rotation matrix ER:

the nutation matrix NR calculation method comprises the following steps:

NR＝R_X(--Δ)R_Z(-Δψ)R_X()

wherein the content of the first and second substances,

the calculation method of the age matrix PR comprises the following steps:

calculating the age constant ζ_A、θ_A、Z_A：

Calculating a time offset matrix PR:

PR＝R_Z(-Z_A)R_Y(θ_A)R_Z(-ζ_A)

wherein the content of the first and second substances,

calculating a conversion matrix M from an inertia system to a ground-fixed system according to the earth rotation matrix ER, the nutation matrix NR and the precision matrix PR_ECI2ECF：

M_ECI2ECF＝ER*NR*PR

(2.3) t calculated according to the step (1)₁Position R of time satellite under inertial system_wECIAnd the transformation matrix M of the inertial system to the earth-fixed system calculated in the step (2.2)_ECI2ECFCalculating t₁Position R of time satellite under earth's fixation_wECFThe obtained satellite position variation curve under the earth-fixed system is shown in fig. 6:

R_wECF＝M_ECI2ECF*R_wECI

(3) the antenna position module of the ground fixed system survey station: according to the longitude, latitude and elevation of the given ground measurement station antenna, the position R of the ground measurement station antenna under the ground fixation system is calculated_tECF. The specific calculation process is as follows:

calculating coordinate components G1 and G2 according to longitude lon, latitude lat and elevation h of the ground station antenna:

wherein f is the geometric oblateness of the earth ellipsoid, and f is 1/298.257.

Computing groundPosition R of antenna of surface measuring station under ground fixing system_tECF：

The calculation results are (unit is meter):

(4) a station-based satellite position module: t calculated according to the step (2)₁Position R of time satellite under earth's fixation_wECFAnd the position R of the ground survey station antenna calculated in the step (3) under the ground system_tECFCalculating t₁Position R of time satellite under the system of the center of the station_wCT. The method comprises the following specific steps:

(4.1) under the station center system, calculating a conversion matrix M from the earth fixed system to the station center system_ECF2CTDescribed as the next rotation about the Z axis and one rotation about the X axis in the earth fixation system:

M_ECF2CT＝R_x(90°-lat)R_z(90°+lon)

wherein the content of the first and second substances,

(4.2) t calculated according to the step (2)₁Position R of time satellite under earth's fixation_wECFThe position R of the ground survey station antenna under the ground fixation system obtained by the calculation in the step (3)_tECFThe conversion matrix M from the earth fixation system to the station center system calculated in the step (4.1)_ECF2CTTranslating the origin of coordinates from the geocentric to the antenna of the ground survey station, and calculating t₁Position R of time satellite under the system of the center of the station_wCTNamely, the projection of the direction vector of the station antenna to the satellite under the station center system, and the obtained direction vector of the station antenna to the satelliteThe projection variation curve of the vector under the station center system is shown in FIG. 7:

R_wCT＝M_ECF2CT*(R_wECF-R_tECF)

(5) the survey station antenna pointing guidance angle module: calculating t according to the position of the satellite under the station center system calculated in the step (4)₁The antenna pointing guide angle of the ground survey station at the moment: high and low angleHorizontal angle psi. The specific calculation process is as follows:

assuming that the position of the ground survey station is located at the origin of the station center system, the projection of the antenna pointing vector of the survey station under the station center system is R_wCTRecord R_wCTComprises the following steps:

calculating elevation angle of antenna pointing guiding angleThe horizontal angle ψ is:

and according to x_CT、y_CT、z_CTPositive and negative of (2), angle of elevationThe horizontal angle ψ is divided into corresponding angle ranges to complete the antenna pointing guidance process, and the obtained change curve of the pointing guidance angle of the antenna of the survey station is shown in fig. 8:

in the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

Those skilled in the art will appreciate that, in addition to implementing the systems, apparatus, and various modules thereof provided by the present invention in purely computer readable program code, the same procedures can be implemented entirely by logically programming method steps such that the systems, apparatus, and various modules thereof are provided in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Therefore, the system, the device and the modules thereof provided by the present invention can be considered as a hardware component, and the modules included in the system, the device and the modules thereof for implementing various programs can also be considered as structures in the hardware component; modules for performing various functions may also be considered to be both software programs for performing the methods and structures within hardware components.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.