CN110208797B - Quick-response SAR satellite high squint attitude maneuver method - Google Patents
Quick-response SAR satellite high squint attitude maneuver method Download PDFInfo
- Publication number
- CN110208797B CN110208797B CN201910446779.2A CN201910446779A CN110208797B CN 110208797 B CN110208797 B CN 110208797B CN 201910446779 A CN201910446779 A CN 201910446779A CN 110208797 B CN110208797 B CN 110208797B
- Authority
- CN
- China
- Prior art keywords
- satellite
- coordinate system
- time
- center
- squint
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 208000004350 Strabismus Diseases 0.000 title claims abstract description 99
- 238000000034 method Methods 0.000 title claims abstract description 26
- 230000004044 response Effects 0.000 title claims abstract description 18
- 239000013598 vector Substances 0.000 claims abstract description 94
- 238000003384 imaging method Methods 0.000 claims abstract description 43
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 239000011159 matrix material Substances 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 6
- 239000004576 sand Substances 0.000 claims description 5
- 238000002347 injection Methods 0.000 claims description 3
- 239000007924 injection Substances 0.000 claims description 3
- 230000002123 temporal effect Effects 0.000 claims description 2
- 230000009466 transformation Effects 0.000 claims description 2
- 230000008859 change Effects 0.000 abstract description 4
- 238000005070 sampling Methods 0.000 abstract description 4
- 238000010586 diagram Methods 0.000 description 8
- 230000008569 process Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000006855 networking Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
Images
Landscapes
- Radar Systems Or Details Thereof (AREA)
Abstract
A quick-response SAR satellite large squint attitude maneuver method comprises the following steps: 1) determining the moment when the relative speed of the scene center and the satellite is zero; 2) calculating the squint observation center time, and the position vector and the velocity vector of the squint observation center time satellite in the geocentric fixed coordinate system; 3) calculating the imaging starting time and the imaging ending time of the strabismus observation; 4) calculating satellite attitude maneuver parameters at the moment of observing the center by squint; 5) in the time range from the beginning to the end of the squint observation, the satellite maneuvers according to attitude maneuvering parameters of the squint observation center moment; 6) and (4) the reserved wave beams are injected with interfaces at a distance angle and an azimuth angle in a satellite body coordinate system, and the wave beam direction is corrected according to the on-orbit wave beam direction calibration value. The invention ensures that the antenna beam points to the target accurately when the quick response SAR satellite observes in a large squint way, and the Doppler frequency change of the distance to each sampling point meets the imaging requirement.
Description
Technical Field
The invention belongs to the technical field of space microwave remote sensing, and relates to a quick response SAR satellite high squint attitude maneuver method.
Background
In order to improve the observation efficiency and the discrimination capability of the satellite-borne SAR on the military target, the military target needs to be subjected to multiple multi-angle observation imaging within the range from front view to back view in a left/right side view monorail. If the phase scanning mode is used to realize the front/back view beam scanning in the left/right side view single track, a huge number of TR modules, feed networks, thermal control networks and the like are needed to ensure the electrical performance during the antenna beam scanning. However, these TR units and networks will greatly increase the overall star weight, power consumption, and development costs. The antenna beam scanning is driven by a maneuvering mode of the quick-response SAR satellite, so that the problems can be effectively avoided, the quick-response SAR satellite needs to be accurately controlled, otherwise, the attitude deviation of the satellite directly causes the deviation of the beam pointing, the observation efficiency of military targets is reduced, and the squint SAR image processing complexity is increased.
Disclosure of Invention
The technical problem solved by the invention is as follows: the method overcomes the defects of the prior art, provides a quick-response SAR satellite large squint attitude maneuver method, ensures that an antenna beam accurately points to a target during the large squint observation of the quick-response SAR satellite, and simultaneously, the Doppler frequency change of the distance to each sampling point meets the imaging requirement.
The technical scheme of the invention is as follows: a quick response SAR satellite large squint attitude maneuver method comprises the following steps:
1) determining the time when the relative speed of the scene center and the satellite is zero according to the position vector of the target scene center in the geocentric fixed coordinate system, the time of passing through the scene orbit satellite, the position of the passing scene orbit satellite in the geocentric fixed coordinate system and the speed vector;
2) calculating the squint observation center time and the position vector and the velocity vector of the squint observation center time satellite in the geocentric fixed coordinate system according to the time when the relative speed of the scene center and the satellite is zero and the imaging requirement squint angle;
3) calculating the imaging starting time and the imaging ending time of the strabismus observation according to the strabismus observation center time, the position velocity vector of the strabismus observation center time satellite in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam azimuth width and the imaging azimuth width;
4) calculating attitude maneuver parameters of the satellite at the squint observation center time according to the squint observation center time, the position velocity vector of the satellite at the squint observation center time in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam pointing distance azimuth angle and the attitude rotation sequence;
5) in the time range from the beginning to the end of the squint observation, the satellite maneuvers according to attitude maneuvering parameters of the squint observation center moment;
6) and (4) the reserved wave beams are injected with interfaces at a distance angle and an azimuth angle in a satellite body coordinate system, and the wave beam direction is corrected according to the on-orbit wave beam direction calibration value.
Determining the time T at which the relative speed of the scene center and the satellite is zero according to the position vector of the target scene center in the geocentric fixed coordinate system, the time of passing the scene orbit segment satellite, and the position and speed vector of the passing scene orbit segment satellite in the geocentric fixed coordinate systemsThe method comprises the following specific steps:
setting the position vector of the scene center in the geocentric fixed coordinate system as RtThere is a time T among the times of the satellites that pass the scene orbit segmentsSo that the relative speed of the scene center and the satellite
Will time TsIs recorded as the relative velocity zero time of the scene center and the satellite, wherein RsAnd VsFor this time, the satellite has a position vector and a velocity vector, R, in the geocentric stationary coordinate systemstThis is the distance of the satellite from the center of the scene at that time.
The time T according to the relative speed of the scene center and the satellite being zerosAnd required squint angle for imaging
Calculating the central time T of strabismus observationsquit0The satellite is on the ground at the time of the squint observation centerPosition vector R in the heart-fixed coordinate systems_squint0And velocity vector Vs_squint0The method comprises the following specific steps:
the time corresponding to the maximum maneuvering capability of the platform pitching forwards or backwards is set to be delta TmaxIn the satellite mobile imaging time range [ Ts-ΔTmax,Ts+ΔTmax]Within, there is a satellite time Tsquit0So that the oblique angle of the satellite pointing to the center of the scene at the moment is the oblique angle required by imaging, namely the oblique angle is satisfied
Rs_squint0For this purpose, the satellite position vector, V, in the geocentric stationary coordinate systems_squint0For this purpose, the satellite has a velocity vector in the geocentric stationary coordinate system.
Observing the central time T according to the squintsquit0And the position vector R of the oblique observation center time satellite in the geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0The position vector R of the scene center in the geocentric fixed coordinate systemtAzimuth width θ of beambwAnd an imaging azimuth width LazCalculating the imaging start time T of the strabismus observationstart＝Tsquit0-0.5TimageAnd an end time Tend＝Tsquit0+0.5TimageWherein
In order to observe the imaging duration in an oblique view,
to look at the beam footprint velocity at the center time of the survey,
for squinting observing central scene central geocentric opening angle, Rst_squint0＝|Rt-Rs_squint0And | is the distance between the satellite and the center of the scene at the moment of observing the center obliquely.
Observing the central time T according to the squintsquit0StrabismusPosition vector R of observation center time satellite in geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0The position vector R of the scene center in the geocentric fixed coordinate systemtBeam pointing distance angle thetaelAnd azimuth angle thetaazAnd posture conversion sequence 1-2-3, calculating the central time T of the squint observationsquit0The method comprises the following steps of (1) satellite attitude maneuver parameters of roll angle, pitch angle pitch and yaw angle yaw:
firstly, establishing a three-axis pointing model of an antenna beam coordinate system of the squint observation center time in a geocentric fixed coordinate system, and forming an antenna beam coordinate system Z of the squint observation center timebeamThe axis pointing to the center of the scene
By simultaneously agreeing on the Y of the antenna beam coordinate systembeamAxis pointing as the antenna beam coordinate system ZbeamAnd the direction of the normal to the plane in which the satellite velocity vector lies, i.e.
(wherein,
) X of the antenna beam coordinate systembeamThe axes satisfy the rule of the right-hand coordinate system
Secondly, according to the distance angle theta of the wave beam in the satellite body coordinate systemelAnd azimuth angle thetaazDetermining the coordinate system X of the satellite bodybThe axes being directed in the Earth's fixed coordinate system at Xb＝Xbeamcosθaz-Ybeamsinθazsinθtemp+ZbeamsinθazcosθtempSatellite body coordinate system YbThe axes pointing in the centroid fixed coordinate system as Yb＝Ybeamcosθtemp+ZbeamsinθtempZ coordinate system of satellite bodybThe axes are directed in a fixed coordinate system of the earth's centerZb＝-Xbeamsinθaz-Ybeamcosθazsinθtemp+ZbeamcosθazcosθtempWherein thetatemp＝arctan(tanθelcosθaz) To define the temporal angle of the aiding calculations.
Finally, according to the satellite position vector R in the geocentric fixed coordinate system of the central moment of the oblique observations_squint0Velocity vector Vs_squint0And the attitude control conversion sequence 1-2-3 calculates the attitude maneuver parameter roll as arcsin (-M)atti(3,2)/cos (pitch)), pitch angle pitch ═ arcsin (M)atti(3,1)) and yaw angle, yaw ═ arcsin (-M)atti(2,1)/cos (pitch)), wherein Matti＝[Me2oXb Me2oYb Me2oZb]TIn the form of a matrix of poses,
is a transformation matrix from the geocentric fixed coordinate system to the satellite orbit coordinate system,
and
for temporary auxiliary calculation of variables, Rs_squint0And Vs_squint0Are all row vectors.
And in the time range from the beginning to the end of the strabismus observation, the satellite maneuvers according to a roll angle roll, a pitch angle pitch and a yaw angle yaw in attitude maneuvering parameters of the strabismus observation center moment.
Distance angle theta of reserved wave beam in satellite body coordinate systemelAnd azimuth angle thetaazAnd the upper injection interface corrects the beam direction according to the on-orbit beam direction calibration value.
Compared with the prior art, the invention has the advantages that:
1. compared with the traditional phase scanning method, the method has the advantages that under the condition that the complexity, the weight and the power consumption of the SAR load system are not increased, the mechanical rotation of the quick-response SAR satellite platform drives the large-caliber antenna to carry out large squint strip beam scanning, multiple multi-angle large squint observation imaging in the range from front view to back view in the left/right side view monorail can be realized, multiple SAR images in a multiple multi-angle high-quality large squint strip mode are obtained, and the observation efficiency and the identification capability of the quick-response SAR satellite on military targets are improved.
2. According to the quick response SAR satellite large squint attitude maneuver method, the peak gain of an antenna beam cannot be attenuated in the multi-angle large squint scanning process, an antenna directional diagram cannot be distorted, the directional diagram is kept symmetrical all the time and is free of interference of grating lobes, the satellite attitude is accurately controlled, so that the maximum value of the antenna beam gain always points to a target scene, the processing complexity of a large squint SAR image is reduced, and the consistency of the signal-to-noise ratio of the SAR image observed at each angle in the range from front view to back view is ensured. .
3. The algorithm is simple in logic and convenient to develop and implement. The method has the advantages that the parameter calculation and acquisition speed is high, the method is suitable for multiple multi-angle large squint strip imaging of a single star in a left/right side view monorail, and meanwhile, the multi-star in-orbit autonomous planning networking can be realized, so that the rapid revisit observation of military targets and the track establishment of moving targets are realized.
Drawings
Fig. 1 is a design flow diagram of the method for maneuvering a large squint attitude of a fast-response SAR satellite according to the present invention.
Fig. 2 is a schematic diagram of a relationship between a large squint observation center time of a fast-response SAR satellite and a relative speed zero time of a scene center satellite.
Fig. 3 is a schematic diagram of beam scanning in a large squint observation time range of a fast-response SAR satellite.
Fig. 4 is a block diagram of conversion from triaxial vectors to attitude maneuver parameters of a satellite body coordinate system under a geocentric fixed coordinate system.
Detailed Description
In order to ensure that the antenna beam points to a target accurately when a fast-response SAR satellite is observed in a large squint manner and the Doppler frequency change of the distance to each sampling point meets the imaging requirement, the invention is designed by the process given in FIG. 1: the method comprises the steps that firstly, the relative speed of a scene center and a satellite is calculated to be zero time according to a position vector of a target scene center in a geocentric fixed coordinate system, the time of passing through a scene orbit satellite and a position speed vector of the passing scene orbit satellite in the geocentric fixed coordinate system; secondly, calculating the squint observation center time, the satellite position vector and the velocity vector of the squint observation center time in the geocentric fixed coordinate system according to the time when the relative speed of the scene center and the satellite is zero and the imaging requirement squint angle; thirdly, calculating the imaging starting time and the imaging ending time of the strabismus observation according to the strabismus observation center time, the position velocity vector of the strabismus observation center time satellite in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam azimuth width and the imaging azimuth width; fourthly, calculating attitude maneuver parameters of the satellite at the oblique observation center time according to the oblique observation center time, the position velocity vector of the satellite at the oblique observation center time in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam pointing distance azimuth angle and the attitude rotation sequence; fifthly, maneuvering the satellite according to attitude maneuvering parameters of the squint observation center moment within the time range from the beginning to the end of the squint observation; and sixthly, reserving a beam, injecting an interface in a distance angle and an azimuth angle in a satellite body coordinate system, and correcting the beam direction according to the on-orbit beam direction calibration value. .
The method comprises the following specific contents:
1) determining the moment when the relative speed of the scene center and the satellite is zero according to the position vector of the scene center in the geocentric fixed coordinate system, the moment of passing through the scene orbit satellite and the position velocity vector of the passing scene orbit satellite in the geocentric fixed coordinate system
The satellite time when the result of the calculation formula (1) of the relative speed between the scene center and the satellite in the geocentric fixed coordinate system is zero is the time T when the relative speed between the scene center and the satellite is zerosE.g. T in satellite orbit in FIG. 2sAt the position, the three-dimensional coordinate vector of the satellite position in the corresponding geocentric fixed coordinate system is RsAnd velocity vector Vs，RstThe distance between the scene center and the satellite and the target at the moment when the relative speed of the satellite is zero.
In the formula, RtAnd fixing the position vector in the coordinate system for the geocentric.
2) Calculating the imaging center time T of the squint observation according to the relative speed zero time of the scene center and the satellite and the imaging demand squint anglesquit0And the satellite position vector R of the central moment of the strabismus observation in the geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0Determining
The scene center squint angle is equal to the imaging requirement squint angle within the range of the search platform with the maximum maneuvering capability in the pitching direction
Satellite time of (c):
Tsearch＝Ts-ΔTmax:Tspace:Ts+ΔTmax (2)
in the formula,. DELTA.TmaxThe time corresponding to the maximum maneuvering capacity of the platform in the pitching forward direction or the back view is Tspace, and the Tspace is a search time interval. Interpolation or track prediction to obtain TsearchTime of day satellite position vector Rs_searchAnd velocity vector Vs_searchThen T issearchThe pointing vector from the satellite to the center of the target scene in the geocentric fixed coordinate system at the moment is as follows:
Rst_search＝Rt-Rs_search (3)
then TsearchThe squint angle from the time satellite to the center of the target scene is as follows:
t in satellite orbit as shown in FIG. 2squint0At a position of
And input required squint angle
Minimum deviation TsearchThe moment is the squint observation imaging center moment Tsquint0The satellite position vector in the corresponding geocentric fixed coordinate system is Rs_squint0The satellite velocity vector in the corresponding geocentric fixed coordinate system is Vs_squint0。
3) Calculating the starting time and the ending time of the strabismus observation according to the strabismus observation center time, the position velocity vector of the strabismus observation center time satellite in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam azimuth width and the imaging azimuth width
The distance from the satellite position of the oblique observation center moment to the center of the target scene in the geocentric fixed coordinate system is as follows:
Rst_squint0＝|Rt-Rs_squint0| (5)
width in beam azimuth thetabwAnd oblique view imaging azimuth width LazNext, the imaging duration of the squint observation is:
in the formula,
(
the geocentric angle of the scene center at the oblique observation center moment). As shown in FIG. 3, the imaging start time T in the satellite orbitstartAnd an imaging end time TendRespectively as follows:
Tstart＝Tsquint0-0.5Timage (7)
Tstart＝Tsquint0+0.5Timage (8)
4) according to the squint observation center time, the position velocity vector of the satellite in the geocentric fixed coordinate system at the squint observation center time and the middle position of the scene center in the geocentric fixed coordinate systemSetting vectors, beam pointing distance angles and attitude rotation sequences to calculate satellite maneuvering parameters of squint observation center time, and in order to meet the requirement that a beam points to a target scene accurately, in a geocentric fixed coordinate system, calculating the squint observation center time Tsquint0The center of the antenna beam points to the center R of the target scenetAnd meanwhile, in order to minimize the Doppler frequency space-variant of the wave beam distance to each echo sampling point, the Y of the antenna wave beam coordinate system is appointedbeamPointing in the direction of the normal to the plane of the centre of the antenna beam and the satellite velocity vector, X of the coordinate system of the antenna beambeamIf the pointing direction meets the rule of the right-hand coordinate system, the three-axis pointing model of the antenna beam coordinate system in the geocentric fixed coordinate system is as follows:
in the formula,
according to the distance angle and the azimuth angle of the wave beam in the satellite body coordinate system (the distance angle and the azimuth angle of the wave beam in the satellite body coordinate system take the installation deviation between the antenna and the satellite before transmission into consideration), the unit vector of the three-axis pointing direction in the earth center fixed coordinate system of the satellite body coordinate system is determined as follows:
in the formula, thetaazFor beams X in the satellite body coordinate systembZbIn-plane deviation ZbAzimuth angle of the axis, thetaelFor beams Y in the satellite body coordinate systembZbIn-plane deviation ZbDistance angle of the axis, defining a secondary calculated time angle thetatemp＝arctan(tanθelcosθaz)。
According to the position vector, the speed vector and the attitude control rotation sequence of the satellite in the geocentric fixed coordinate system at the time of observing the center by strabismus, the triaxial vector of the satellite body coordinate system in the geocentric fixed coordinate system is converted into attitude maneuver parameters for the attitude control subsystem to use according to the diagram shown in FIG. 4.
Calculating a conversion matrix from the geocentric fixed coordinate system to the satellite orbit coordinate system according to the satellite position vector and the velocity vector in the geocentric fixed coordinate system at the time of observing the center at the strabismus, wherein the conversion matrix is as follows:
in the formula,
Rs_squint0and Vs_squint0Are all row vectors, Rs_squint0(1) Fixing the vector R in the coordinate system for the centroids_squint0X-axis component of (2), Rs_squint0(2) Fixing the vector R in the coordinate system for the centroids_squint0The Y-axis component of (a).
The three-axis vectors of the satellite body coordinate system in the satellite orbit coordinate system are respectively as follows:
Xbo＝Me2oXb
Ybo＝Me2oYb
Zbo＝Me2oZb (12)
in the formula, Xb，Yb，ZbAre all column vectors.
Then the three-axis vector of the satellite body coordinate system in the satellite orbit coordinate system can obtain an attitude matrix as follows:
Matti＝[Xbo Ybo Zbo]T (13)
if maneuvering parameters of roll, pitch and yaw are respectively as follows under the 1-2-3 rotation sequence:
roll＝arcsin(-Matti(3,2)/cos(pitch)) (14)
pitch＝arcsin(Matti(3,1)) (15)
yaw＝arcsin(-Matti(2,1)/cos(pitch)) (16)
5) within the time range from the beginning to the end of the strabismus observation, the satellite maneuvers according to attitude maneuvering parameters of the strabismus observation center moment
On-orbit strabismus imaging time range Tstart～TendAnd the satellite can realize large squint strip observation imaging according to roll angle, pitch angle and yaw angle maneuvering shown in formulas (14) to (16), the roll angle, the pitch angle and the yaw angle are unchanged (the corresponding attitude angular velocity is 0) in the whole imaging time range, and the schematic diagram of scanning the target scene by the large squint beam of the fast-sounding SAR satellite in the whole imaging time range is shown in figure 3.
6) And (4) the reserved wave beams are injected with interfaces at a distance angle and an azimuth angle in a satellite body coordinate system, and the wave beam direction is corrected according to the on-orbit wave beam direction calibration value.
Meanwhile, in order to correct beam pointing deviation caused by emission oscillation and environmental change, a distance angle and an azimuth angle upper injection interface of a beam in a satellite body coordinate system are reserved, and the on-orbit periodic updating is carried out to be a ground calibration value.
The invention is not described in detail and is within the knowledge of a person skilled in the art.
Claims (2)
1. A quick response SAR satellite large squint attitude maneuver method is characterized by comprising the following steps:
1) determining the time when the relative speed of the scene center and the satellite is zero according to the position vector of the target scene center in the geocentric fixed coordinate system, the time of passing through the scene orbit satellite, the position of the passing scene orbit satellite in the geocentric fixed coordinate system and the speed vector;
2) calculating the squint observation center time and the position vector and the velocity vector of the squint observation center time satellite in the geocentric fixed coordinate system according to the time when the relative speed of the scene center and the satellite is zero and the imaging requirement squint angle;
3) calculating the imaging starting time and the imaging ending time of the strabismus observation according to the strabismus observation center time, the position velocity vector of the strabismus observation center time satellite in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam azimuth width and the imaging azimuth width;
4) calculating attitude maneuver parameters of the satellite at the squint observation center time according to the squint observation center time, the position velocity vector of the satellite at the squint observation center time in the geocentric fixed coordinate system, the position vector of the scene center in the geocentric fixed coordinate system, the beam pointing distance azimuth angle and the attitude rotation sequence;
5) in the time range from the beginning to the end of the squint observation, the satellite maneuvers according to attitude maneuvering parameters of the squint observation center moment;
6) reserving a distance angle and an azimuth angle upper injection interface of a wave beam in a satellite body coordinate system, and correcting the wave beam direction according to the on-orbit wave beam direction calibration value;
determining the time T at which the relative speed of the scene center and the satellite is zero according to the position vector of the target scene center in the geocentric fixed coordinate system, the time of passing the scene orbit segment satellite, and the position and speed vector of the passing scene orbit segment satellite in the geocentric fixed coordinate systemsThe method comprises the following specific steps:
setting the position vector of the scene center in the geocentric fixed coordinate system as RtThere is a time T among the times of the satellites that pass the scene orbit segmentsSo that the relative speed of the scene center and the satellite
Will time TsIs recorded as the relative velocity zero time of the scene center and the satellite, wherein RsAnd VsFor this time, the satellite has a position vector and a velocity vector, R, in the geocentric stationary coordinate systemstThe distance between the satellite and the scene center at the moment;
the time T according to the relative speed of the scene center and the satellite being zerosAnd required squint angle for imaging
Calculating the central time T of strabismus observationsquit0And the position vector R of the oblique observation center time satellite in the geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0The method comprises the following specific steps:
the time corresponding to the maximum maneuvering capability of the platform pitching forwards or backwards is set to be delta TmaxIn the satellite mobile imaging time range [ Ts-ΔTmax,Ts+ΔTmax]Within, there is a satellite time Tsquit0So that the oblique angle of the satellite pointing to the center of the scene at the moment is the oblique angle required by imaging, namely the oblique angle is satisfied
Rs_squint0For this purpose, the satellite position vector, V, in the geocentric stationary coordinate systems_squint0The satellite velocity vector in the geocentric fixed coordinate system at the moment;
observing the central time T according to the squintsquit0And the position vector R of the oblique observation center time satellite in the geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0The position vector R of the scene center in the geocentric fixed coordinate systemtAzimuth width θ of beambwAnd an imaging azimuth width LazCalculating the imaging start time T of the strabismus observationstart＝Tsquit0-0.5TimageAnd an end time Tend＝Tsquit0+0.5TimageWherein
In order to observe the imaging duration in an oblique view,
to look at the beam footprint velocity at the center time of the survey,
for squinting observing central scene central geocentric opening angle, Rst_squint0＝|Rt-Rs_squint0I is the distance between the satellite and the scene center at the moment of observing the center by squint;
observing the central time T according to the squintsquit0And strabismus observationPosition vector R of center time satellite in geocentric fixed coordinate systems_squint0And velocity vector Vs_squint0The position vector R of the scene center in the geocentric fixed coordinate systemtBeam pointing distance angle thetaelAnd azimuth angle thetaazAnd posture conversion sequence 1-2-3, calculating the central time T of the squint observationsquit0The method comprises the following steps of (1) satellite attitude maneuver parameters of roll angle, pitch angle pitch and yaw angle yaw:
firstly, establishing a three-axis pointing model of an antenna beam coordinate system of the squint observation center time in a geocentric fixed coordinate system, and forming an antenna beam coordinate system Z of the squint observation center timebeamThe axis pointing to the center of the scene
By simultaneously agreeing on the Y of the antenna beam coordinate systembeamAxis pointing as the antenna beam coordinate system ZbeamAnd the direction of the normal to the plane in which the satellite velocity vector lies, i.e.
Wherein,
x of antenna beam coordinate systembeamThe axes satisfy the rule of the right-hand coordinate system
Secondly, according to the distance angle theta of the wave beam in the satellite body coordinate systemelAnd azimuth angle thetaazDetermining the coordinate system X of the satellite bodybThe axes being directed in the Earth's fixed coordinate system at Xb＝Xbeamcosθaz-Ybeamsinθazsinθtemp+ZbeamsinθazcosθtempSatellite body coordinate system YbThe axes pointing in the centroid fixed coordinate system as Yb＝Ybeamcosθtemp+ZbeamsinθtempZ coordinate system of satellite bodybIs axially arranged atThe orientation in the earth's center fixed coordinate system is Zb＝-Xbeamsinθaz-Ybeamcosθazsinθtemp+ZbeamcosθazcosθtempWherein thetatemp＝arc tan(tanθelcosθaz) To define the temporal angle of the aiding calculation;
finally, according to the satellite position vector R in the geocentric fixed coordinate system of the central moment of the oblique observations_squint0Velocity vector Vs_squint0And the attitude control conversion sequence 1-2-3 calculates the attitude maneuver parameter roll as arcsin (-M)atti(3,2)/cos (pitch)), pitch angle pitch ═ arcsin (M)atti(3,1)) and yaw angle, yaw ═ arcsin (-M)atti(2,1)/cos (pitch)), wherein Matti＝[Me2oXb Me2oYb Me2oZb]TIn the form of a matrix of poses,
is a transformation matrix from the geocentric fixed coordinate system to the satellite orbit coordinate system,
and
for temporary auxiliary calculation of variables, Rs_squint0And Vs_squint0Are all row vectors.
2. The method of claim 1, wherein the method comprises the following steps: and in the time range from the beginning to the end of the strabismus observation, the satellite maneuvers according to a roll angle roll, a pitch angle pitch and a yaw angle yaw in attitude maneuvering parameters of the strabismus observation center moment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910446779.2A CN110208797B (en) | 2019-05-27 | 2019-05-27 | Quick-response SAR satellite high squint attitude maneuver method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910446779.2A CN110208797B (en) | 2019-05-27 | 2019-05-27 | Quick-response SAR satellite high squint attitude maneuver method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110208797A CN110208797A (en) | 2019-09-06 |
| CN110208797B true CN110208797B (en) | 2021-02-09 |
Family
ID=67788711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910446779.2A Active CN110208797B (en) | 2019-05-27 | 2019-05-27 | Quick-response SAR satellite high squint attitude maneuver method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110208797B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112462365B (en) * | 2020-09-21 | 2024-05-24 | 北京理工大学 | Space-borne scene matching SAR data acquisition configuration optimization design method |
| CN113091728B (en) * | 2021-03-11 | 2023-02-28 | 上海卫星工程研究所 | Method and system for acquiring ground multi-target access window by satellite |
| CN115276760B (en) * | 2022-06-24 | 2023-06-23 | 中国联合网络通信集团有限公司 | Beam center position determining method and device and computer storage medium |
| CN115616576B (en) * | 2022-12-16 | 2023-03-10 | 西安空间无线电技术研究所 | SAR antenna directional pattern correction method and device under large squint imaging |
| CN115792907B (en) * | 2023-02-07 | 2023-04-14 | 中国科学院空天信息创新研究院 | Method for designing azimuth imaging parameters of spaceborne SAR squint sliding bunching mode |
| CN116699613B (en) * | 2023-08-04 | 2023-10-13 | 中国科学院空天信息创新研究院 | On-orbit accurate calculation method for scanning mode imaging starting time |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103983254A (en) * | 2014-04-22 | 2014-08-13 | 航天东方红卫星有限公司 | Novel imaging method in agile satellite maneuvering |
| CN104848860A (en) * | 2015-05-19 | 2015-08-19 | 北京空间飞行器总体设计部 | Method for planning attitude maneuver in imaging process of agile satellite |
| CN106226768A (en) * | 2016-08-09 | 2016-12-14 | 北京空间飞行器总体设计部 | Ultrahigh resolution agility SAR satellite slip beam bunching mode System Parameter Design method |
| CN106291557A (en) * | 2016-08-30 | 2017-01-04 | 西安空间无线电技术研究所 | A kind of satellite platform attitude maneuver method realizing satellite-borne SAR ultrahigh resolution slip beam bunching mode |
| CN107300700A (en) * | 2016-04-15 | 2017-10-27 | 北京空间飞行器总体设计部 | Quick Synthetic Aperture Radar satellite beam bunching mode attitude maneuver demand computational methods |
| CN107505615A (en) * | 2017-08-22 | 2017-12-22 | 西安电子科技大学 | Satellite-borne SAR slides spotlight imaging pattern celestial body posture design method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101320508B1 (en) * | 2012-09-13 | 2013-10-23 | 국방과학연구소 | Device for efficiency test of synthetic aperture radar |
| CN106249237B (en) * | 2016-07-19 | 2019-05-21 | 西安电子科技大学 | Big Squint SAR frequency domain imaging method under a kind of curvilinear path |
-
2019
- 2019-05-27 CN CN201910446779.2A patent/CN110208797B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103983254A (en) * | 2014-04-22 | 2014-08-13 | 航天东方红卫星有限公司 | Novel imaging method in agile satellite maneuvering |
| CN104848860A (en) * | 2015-05-19 | 2015-08-19 | 北京空间飞行器总体设计部 | Method for planning attitude maneuver in imaging process of agile satellite |
| CN107300700A (en) * | 2016-04-15 | 2017-10-27 | 北京空间飞行器总体设计部 | Quick Synthetic Aperture Radar satellite beam bunching mode attitude maneuver demand computational methods |
| CN106226768A (en) * | 2016-08-09 | 2016-12-14 | 北京空间飞行器总体设计部 | Ultrahigh resolution agility SAR satellite slip beam bunching mode System Parameter Design method |
| CN106291557A (en) * | 2016-08-30 | 2017-01-04 | 西安空间无线电技术研究所 | A kind of satellite platform attitude maneuver method realizing satellite-borne SAR ultrahigh resolution slip beam bunching mode |
| CN107505615A (en) * | 2017-08-22 | 2017-12-22 | 西安电子科技大学 | Satellite-borne SAR slides spotlight imaging pattern celestial body posture design method |
Non-Patent Citations (5)
| Title |
|---|
| Analytic Yaw–Pitch Steering for Side-Looking SAR With Numerical Roll Algorithm for Incidence Angle;Daniel P. Scharf等;《 IEEE Transactions on Geoscience and Remote Sensing》;20120307;第50卷(第9期);全文 * |
| Attitude maneuver strategy for sliding spotlight SAR satellite with hight resolution;C.Zhou等;《Systems Engineering and Electronics》;20180731;第40卷(第7期);全文 * |
| 一种卫星快速姿态机动及稳定控制方法;冯佳佳;《中国空间科学技术》;20170825;第37卷(第4期);全文 * |
| 快响SAR卫星零多普勒波束中心姿态机动策略研究;贺荣荣等;《中国空间科学技术》;20180825;第38卷(第4期);全文 * |
| 高分辨率滑动聚束SAR卫星姿态机动策略;周超伟等;《系统工程与电子技术》;20180731;第40卷(第7期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110208797A (en) | 2019-09-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110208797B (en) | Quick-response SAR satellite high squint attitude maneuver method | |
| CN110515078B (en) | Wave position design method for airspace coverage | |
| CN107132537B (en) | A kind of SAR satellite on-orbit performance method for improving based on electromechanical combination scanning | |
| US4546354A (en) | Range/azimuth ship imaging for ordnance control | |
| CN115792907B (en) | Method for designing azimuth imaging parameters of spaceborne SAR squint sliding bunching mode | |
| CN107064880A (en) | Distributed many base radar transmit-receive beam Synchronizations and the accuracy method of wave beam control | |
| CN109521424B (en) | Satellite-borne sliding spotlight SAR satellite attitude and PRF sequence design method | |
| CN108663052B (en) | Autonomous space non-cooperative target Relative Navigation camera is directed toward control method on a kind of star | |
| CN108613655B (en) | Attitude adjustment method for imaging along inclined strip in agile satellite machine | |
| CN107300700B (en) | Agile synthetic aperture radar satellite bunching mode attitude maneuver demand calculation method | |
| CN110632935A (en) | Autonomous control method for formation satellite around flight | |
| CN110596704A (en) | Satellite platform attitude maneuver method for satellite-borne SAR multi-azimuth repeated observation | |
| CN116859344A (en) | Energy spectrum self-adaptive distributed InSAR spatial synchronization method oriented to coherent optimization | |
| CN112255606A (en) | Method for calculating front side-view imaging attitude angle of Geo-SAR (synthetic aperture radar) satellite based on single reflector antenna | |
| CN106950566A (en) | A kind of synthetic aperture radar image-forming method and device | |
| Dong et al. | A method of zero Doppler centroid control in GEO SAR | |
| CN106843249B (en) | two-dimensional guiding attitude control method | |
| CN113532372B (en) | Using method of space-based double-satellite intersection angle and distance measuring device | |
| CN106961837B (en) | Leggy Centers multibeam synthetic aperture radar orientation phasing and signal processing method | |
| CN111007506B (en) | Target imaging time window calculation method under satellite sliding bunching mode | |
| Zhou et al. | A Feasible Satellite Attitude Maneuver Strategy for High Resolution Sliding Spotlight SAR | |
| CN116087953B (en) | Satellite-borne SAR multi-target imaging parameter design method | |
| Ruth et al. | Video-guidance design for the DART rendezvous mission | |
| KR20240027824A (en) | Satellite with spotlight mode for long-term target imaging | |
| CN108614250B (en) | Wide-area DBS image splicing dark fringe correction method of airborne battlefield surveillance radar |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |