CN104183920A - Anti-wind-disturbing pointing error compensation method for large beam waveguide antenna - Google Patents

Abstract

The invention belongs to the technical field of antennas, and particularly relates to an anti-wind-disturbing pointing error compensation method for a large beam waveguide antenna. The method includes the steps of (1) calculating a transverse displacement needed by the position of an equivalent feed source, (2) determining a reflection mirror combination of an antenna beam waveguide system and estimating a displacement needed by a mirror surface of a feed-source virtual image primarily, (3) specifically determining sizes of mirror surfaces of all reflection mirrors according to the displacement needed by the mirror surface of the feed-source virtual image and the stroke of a driver, (4) determining the structure of the first reflection mirror, and calculating the displacement needed by azimuth direction drive of the first reflection mirror according to the displacement needed by the feed-source virtual image in an azimuth direction, and (5) calculating the displacement needed by pitching direction drive of the first reflection mirror according to the displacement needed by a feed-source virtual image in the pitching direction. According to the method, the position of the equivalent feed source in a primary surface system is changed in the way that the positions of the mirror surfaces in the beam waveguide system are adjustable in real time, and accordingly pointing deviation of the antenna caused by deformation of the primary surface system as a result of wind disturbing is compensated and pointing accuracy of the antenna is improved.

Description

A kind of error in pointing compensation method of large-scale beam waveguide antenna wind disturbance resistance

Technical field

The invention belongs to antenna technical field, be specifically related to a kind of error in pointing compensation method of large-scale beam waveguide antenna wind disturbance resistance.

Background technology

Large-scale reflector antenna leaks and penetrates the advantages such as low with its illumination efficiency height and edge, be widely used in satellite communication, the fields such as deep space exploration, yet large-scale reflector antenna points to controller design objective and has relatively high expectations, 65 meters of aperture antennas of China's " light of firefly engineering " for example, its pointing accuracy requires error to be less than 0.01 °, only have precision to reach requirement, competence exertion antenna aperture efficiency, and along with the continuous increase of bore, antenna structure can be conducted oneself with dignity, wind lotus, the multiple load such as sleet, make antenna interarea system generation plastic deformation, cause the deviation of pointing to, and point to deviation, can cause that antenna electric performance deviation reduces operating efficiency.Certainly along with the difference of antenna operating mode, this impact also can change thereupon.

For how reducing the impact of extraneous load on Antenna pointing control, forefathers are accurately understanding aspect the factor that error in pointing caused, and advanced control theory aspect made a large amount of contributions, and have all reduced error in pointing to a certain extent, but effect is limited; And for how reducing the error in pointing that external applied load causes, innovation is not proposed from antenna existing structure.

Current international survey of deep space antenna is nearly all to adopt Cassegrain structure, compare with front feed antenna intuitively, Cassegrain antenna, when beam direction points to deep space, can, away from ground, make antenna noise temperature reduction by breadth ovfl to the energy in space.Survey of deep space antenna adopts the situation of beam waveguide feed day by day to increase.This be because: the first, beam waveguide feed feed network system and receiver system can be placed in the equipment room on ground, be convenient to maintenance and operation; The second progress along with radio-frequency spectrum developing technology, survey of deep space frequency range used develops to high band gradually, and multifrequency common technology is day by day ripe, adopts beam waveguide feed system to carry out double frequency or multifrequency separation by double-colored face.

Summary of the invention

The object of the invention is to design a kind of beam waveguide system that can change in real time reflector position, by changing reflector position, change equivalent feed position, the error in pointing causing in order to compensate interarea system variant.

For this reason, the invention provides a kind of error in pointing compensation method of large-scale beam waveguide antenna wind disturbance resistance, comprise the steps:

(1) calculate the required lateral displacement in equivalent feed position;

(2) determine the arrangement of mirrors structure of the beam waveguide system of antenna, utilize the required displacement of feed virtual image minute surface according to a preliminary estimate of this arrangement of mirrors structure;

Determined arrangement of mirrors is dual paraboloid combination, and it comprises three plane mirrors; Feed O through speculum one, speculum two, speculum three, speculum four and speculum five from feed the level crossing away from more and more, speculum two and speculum four are paraboloidal mirror; For the speculum four of paraboloidal mirror can rotate with pitch axis, guaranteed that equivalent feed position rotates and change luffing angle with pitch axis; Adjustable in real time for speculum one position of level crossing, be used for changing the real time position of equivalent feed, if by the virtual image O of feed O ₁move to O ₂, equivalent feed point B ₁also move to B ₂;

(3), according to the stroke of the required minute surface displacement of the feed virtual image and driver, specifically determine each mirror mirror size;

(4) determine the structure of speculum one, according to the required displacement of the azimuth direction feed virtual image, calculate speculum one azimuth direction and drive required displacement; ;

(5) according to the required displacement of the pitch orientation feed virtual image, calculate speculum, obtain equivalent feed point B ₁, wherein speculum one, speculum three and speculum five are followed successively by apart from a pitch orientation and drive required displacement.

The computational methods of the lateral displacement that the described equivalent feed position of above-mentioned steps (1) is required are carried out as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the azimuth direction that the interarea system variant that causes causes _max, and equivalent feed B ₁lateral displacement d _u1can produce error in pointing θ equally ₁, make θ _max+ θ ₁=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{u1}=\frac{{\mathrm{\θ}}_{\max }\mathrm{Mf}}{K}$

Wherein f is primary reflection surface focal length, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

The computational methods of the required displacement of minute surface according to a preliminary estimate that above-mentioned steps (2) is described are:

The required displacement estimation method of minute surface:

If speculum five is θ with x to angle ₂, equivalent feed B ₁to B ₂x to displacement d _u1, can be by the picture F of its equivalent feed ₁move to F ₂y to displacement d _u2calculate gained:

d _u1＝d _u2×sin(180-2θ ₂)

And the focal axis direction of speculum four is x direction, so F ₁to F ₂y to displacement d _u2lateral displacement for the parabolic focus of speculum four, make focus generation lateral displacement, the incident light of speculum four need depart from angle θ of x direction, and this angle θ is the beams incident deflection angle of speculum four, because θ is generally less, therefore do not consider the impact defocusing here.The computational methods of θ are as follows:

$\mathrm{\θ}=\frac{d_{u2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum four, f ₁focal length for speculum four.

Speculum three is with x direction angle at 45 ° and maintain static, according to the refraction principle of light, therefore the beams incident deflection angle theta of speculum four is the reflected beam deflection angle of speculum three, and the reflected beam that needs speculum two is the deflection angle theta that the incident wave beam of speculum three also produces corresponding size; Identical with the parabola principle of speculum four, the focus generation lateral displacement d of needed speculum two _u3, computational methods are as follows:

$d_{u3}=\frac{\mathrm{\θ}{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum two, f ₂focal length for speculum two.

Get: K ₁=K ₂, f ₁=f ₂,

D _u3for minute surface Displacement Estimation value.

The specific design step of above-mentioned steps (3) is as follows:

A. design reflectivity mirror five and x are to angle theta ₂between 45 ° to 55 °, guaranteed like this F ₁to F ₂y to displacement, can't produce larger B ₁to B ₂y to displacement, and affect the gain of interarea system electrical property.

B. design reflectivity mirror four, determine bore D ₁and focal distance f ₁:

After primary reflection surface system is determined, wave beam half angle θ _malso determine; Speculum five and x are to angle theta ₂after determining, for guarantee wave beam vertically towards y to, speculum four reflected beam axis and x are to angle theta ₀also determine bore D ₁except the restriction of structure full-size, in order to reduce edge leakage, penetrate and diffraction phenomenon, also should meet following formula:

D ₁≥30λ

Wherein λ is wavelength.

Again according to D ₁with half angle θ _mdetermine the focal distance f of speculum four ₁, specifically should meet formula as follows:

$p_1=\frac{2f_1}{1+\cos ({\mathrm{\θ}}_0-{\mathrm{\θ}}_m)}$

$p_2=\frac{2f_1}{1+\cos ({\mathrm{\θ}}_0+{\mathrm{\θ}}_m)}$

D ₁＝(p ₂-p ₁)cosθ _m

P wherein ₁, p ₂for the light path of beam edge ripple five of speculum four and speculums.

C. design reflectivity mirror three, and speculum three is 45 ° with x to angle, therefore according to speculum four-hole footpath D ₁, determine speculum three bore D ₂.

D. design reflectivity mirror two, according to required equivalent feed lateral displacement d _u1, minute surface Displacement Estimation value and drive stroke d _x, determine the minute surface combined amplifier factor, then redesign speculum two focal distance f in conjunction with speculum three bores ₂and incident half angle θ _mo.

Minute surface combined amplifier factor-alpha is defined as follows:

$\mathrm{\&alpha;}=\frac{d_{u3}}{d_{u1}}\&ap;\frac{f_2{K}_1}{f_1{K}_2}\&ap;\frac{f_2}{f_1}<\frac{d_x}{d_{u1}}$

Make the bore D of speculum two ₃the same D that is of bore with speculum four ₁, and make speculum two θ ₀=pi/2.

Have:

D ₃＝4f ₂tanθ _mo

E. according to incident half angle θ _moand feed is apart from speculum one distance L, determines speculum one bore D ₄.

D ₄＞2Ltanθ _mo

Described speculum one Mirror frame structure design and the speculum one mirror holder minute surface of above-mentioned steps (4) drives the computational methods of required azimuth direction drive displacement to be:

Speculum one Mirror frame structure method for designing:

When azimuth direction error is pointed in compensation, required equivalent feed B ₁at x, to translation, according to mirror-reflection principle, need the virtual image O of feed ₁be x to translation, and the translation of the virtual image, need speculum one to do plane motion, comprise translation and rotation, in order to simplify driving action direction, design reflectivity mirror one Mirror frame structure, this designs simplification driving type of action: this mirror holder is comprised of guide post and mirror holder, guide post is vertical with mirror holder, mirror restitope is on guide post middle vertical plane, guide post divides three sections, epimere is connected with an axle spring respectively with hypomere with stage casing and stage casing, guaranteed that guide post can axial stretching, hypomere end points is connected with feed revolute pair three, epimere end points makes it be positioned at feed virtual image place, and affixed ball, barycenter place, stage casing guide post is connected by revolute pair two with a connecting rod.Make the ball of this mirror holder in horizontal concrete chute, and mirror holder barycenter place connecting rod is placed in horizontal bush, can guarantee that horizontal displacement is done in the virtual image of speculum one all the time, and mirror holder is positioned on the perpendicular bisector of feed and the virtual image all the time.Mirror holder is secondary by two groups of translations, guaranteed that mirror barycenter and mirror holder one end position only do translational motion all the time, two axle springs have guaranteed that speculum one is positioned on the perpendicular bisector of mirror holder all the time, thereby make mirror holder end points be respectively feed position and virtual image position, therefore only one end need be fixed in to feed place, do the other end load driver power of translational motion.

And when compensation pitch orientation error, required equivalent feed B ₁at z, to translation, according to mirror-reflection principle, need the virtual image O of feed ₁be z to translation; Only level crossing need be rotated and can ignore the movement of the virtual image in xy plane around one end, think the virtual image at z to translation has occurred.Therefore designed mirror holder pitch orientation only needs mirror one end to be connected with mirror holder by revolute, other end load driver power.

Azimuth direction drive displacement is calculated:

Because azimuth direction actuating force directly loads on virtual image position, so drive required displacement to be equal to the required displacement d of the virtual image _u3.

Above-mentioned steps (5) described according to the required displacement of the pitch orientation feed virtual image, calculate speculum one and drive required displacement, calculate as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the pitch orientation that the interarea system variant that causes causes _maxe, and equivalent feed B ₁pitching face in z to displacement d _e1can produce error in pointing θ equally _e1, make θ _maxe+ θ _e1=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{e1}=\frac{{\mathrm{\&theta;}}_{\max e}\mathrm{Mf}}{K}$

Wherein f is primary reflection surface focal length, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

Speculum one drives required displacement computational methods:

Equivalence feed B ₁to B ₂z to displacement d _e1, can be by the picture F of its equivalent feed ₁move to F ₂z to displacement d _e2calculate gained:

d _e1＝d _e2

So F ₁to F ₂z to displacement d _e2lateral displacement for the parabolic focus of speculum four, make focus generation lateral displacement, and the incident light of speculum four departs from its xy plane θ _eangle, due to θ _egenerally less, therefore do not consider the impact defocusing here.θ _ecomputational methods as follows:

${\mathrm{\&theta;}}_e=\frac{d_{e2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum four, f ₁focal length for speculum four.

So beams incident deflection angle theta of speculum four _e, need the reflected beam of speculum two also to produce accordingly and the deflection angle theta of xy plane _e; Identical with the parabola principle of speculum four, there is z to displacement d in the focus of needed speculum two _e3, computational methods are as follows:

$d_{e3}=\frac{{\mathrm{\&theta;}}_e{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum two, f ₂focal length for speculum two.

The focus of speculum two is the virtual image of speculum one, and speculum one virtual image z is d to displacement _e3

If the bore of speculum one is D ₄, feed is L apart from the distance of speculum one, by following formula, can be obtained, speculum one drives required displacement d _d:

d _d＝d _e3D ₄/2L

Beneficial effect of the present invention: the present invention adopts the real-time adjustable method of the mirror position in beam waveguide system, change equivalent feed position in interarea system, thereby compensation is disturbed the interarea system variant causing and the antenna direction deviation causing by wind, has improved the pointing accuracy of antenna.This method advantage: 1) from the structure of large-scale beam waveguide antenna, utilize real-time change reflector position to compensate by wind and disturb caused error in pointing, design the suitable minute surface combined amplifier factor and can greatly reduce the required displacement of driving, in the real-time of compensation, can be guaranteed.2) structural design of unique adjustable speculum one mirror holder, making only needs axially to drive with simple, can realize speculum one and do plane motion (comprising translation and rotation), has avoided complicated type of drive, more convenient and practical.

Below with reference to accompanying drawing, the present invention is described in further details.

Accompanying drawing explanation

Fig. 1 is the inventive method flow chart of steps;

Fig. 2 is antenna interarea system vertical view;

Fig. 3 is the dual paraboloid composite wave beam waveguide system of antenna;

Fig. 4 is speculum four, five combination schematic diagrames;

Fig. 5 is movable plane mirror one structure vertical view;

Fig. 6 is movable plane mirror one mirror holder end view;

Fig. 7 is feed virtual image pitch orientation bit shift compensation schematic diagram;

Description of reference numerals: 1, speculum one; 2, speculum two; 3, speculum three; 4, speculum four; 5, speculum five; 6, feed; 7, interarea system primary reflection surface; 8, interarea system breadth; 9, ball; 10, the first axle spring; 11, mirror holder; 12, the second axle spring; 13, drive electric cylinder one; 14, translation secondary case cylinder; 15, translation axis of traction; 16, the secondary chute of translation; 17, first connecting rod; 18, second connecting rod; 19, third connecting rod; 20, drive electric cylinder two; 21, revolute pair one; 22, revolute pair two; 23, revolute pair three; 24, revolute pair four.

Embodiment

Referring to Fig. 1, and in conjunction with Fig. 2 to Fig. 7, the present invention includes following steps:

(1) calculate the required lateral displacement in equivalent feed position;

(2) determine the arrangement of mirrors structure of the beam waveguide system of antenna, utilize the required displacement of feed virtual image minute surface according to a preliminary estimate of this arrangement of mirrors structure;

Determined arrangement of mirrors is dual paraboloid combination, and it comprises three plane mirrors; Feed O, through speculum 1, speculum 22, speculum 33, speculum 44 and speculum 55, obtains equivalent feed point B ₁, wherein speculum 1, speculum 33 and speculum 55 are followed successively by the level crossing more and more far away apart from feed 6, and speculum 22 and speculum 44 are paraboloidal mirror; For the speculum 44 of paraboloidal mirror can rotate with pitch axis, guaranteed that equivalent feed position rotates and change luffing angle with pitch axis; Adjustable in real time for speculum one 1 positions of level crossing, be used for changing the real time position of equivalent feed, if by the virtual image O of feed O ₁move to O ₂, equivalent feed point B ₁also move to B ₂;

(3), according to the stroke of the required minute surface displacement of the feed virtual image and driver, specifically determine each mirror mirror size;

(4) determine the structure of speculum 1, according to the required displacement of the azimuth direction feed virtual image, calculate speculum one 1 azimuth directions and drive required displacement;

(5), according to the required displacement of the pitch orientation feed virtual image, calculate speculum one 1 pitch orientation and drive required displacement.

The computational methods of the lateral displacement that the described equivalent feed position of step (1) is required are carried out as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the azimuth direction that the interarea system variant that causes causes _max, and equivalent feed B ₁lateral displacement d _u1can produce error in pointing θ equally ₁, make θ _max+ θ ₁=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{u1}=\frac{{\mathrm{\&theta;}}_{\max }\mathrm{Mf}}{K}$

Wherein f is primary reflection surface focal length, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

Look-up table herein (lookuptable) is the art prior art, appear in the article of Japanese author NobuharuUkita, look-up table is according to different wind speed, different wind directions, the maximum of the antenna pointing error that antenna diverse location place records, sets up form, when compensation wind is disturbed error, according to current location and wind speed and direction, look into built form, obtain bearing sense error and the pitching error in pointing of required compensation.

The computational methods of the required displacement of minute surface according to a preliminary estimate that step (2) is described are:

The required displacement estimation method of minute surface:

If speculum 55 is θ with x to angle ₂, equivalent feed B ₁to B ₂x to displacement d _u1, can be by the picture F of its equivalent feed ₁move to F ₂y to displacement d _u2calculate gained:

d _u1＝d _u2×sin(180-2θ ₂)

And the focal axis direction of designed speculum 44 is x direction, so F ₁to F ₂y to displacement d _u2lateral displacement for the parabolic focus of speculum 44, make focus generation lateral displacement, the incident light of speculum 44 need depart from angle θ of x direction, and this angle θ is the beams incident deflection angle of speculum 44, because θ is generally less, therefore do not consider the impact defocusing here.The computational methods of θ are as follows:

$\mathrm{\&theta;}=\frac{d_{u2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum 44, f ₁focal length for speculum 44.

Designed speculum 33 is with x direction angle at 45 ° and maintain static, according to the refraction principle of light, therefore the beams incident deflection angle theta of speculum 44 is the reflected beam deflection angle of speculum 33, and the reflected beam that needs speculum 22 is the deflection angle theta that the incident wave beam of speculum 33 also produces corresponding size; Identical with the parabola principle of speculum 44, the focus generation lateral displacement d of needed speculum 22 _u3, computational methods are as follows:

$d_{u3}=\frac{\mathrm{\&theta;}{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum 22, f ₂focal length for speculum 22.

Get: K ₁=K ₂, f ₁=f ₂, d _u3for minute surface Displacement Estimation value.

The specific design step of step (3) is as follows:

E. design reflectivity mirror 55 and x are to angle theta ₂between 45 ° to 55 °, guaranteed like this F ₁to F ₂y to displacement, can't produce larger B ₁to B ₂y to displacement, and affect the gain of interarea system electrical property.

F. design reflectivity mirror 44, determine bore D ₁and focal distance f ₁:

After primary reflection surface system is determined, wave beam half angle θ _malso determine; Speculum 55 and x are to angle theta ₂after determining, for guarantee wave beam vertically towards y to, speculum 44 reflected beam axis and x are to angle theta ₀also determine bore D ₁except the restriction of structure full-size, in order to reduce edge leakage, penetrate and diffraction phenomenon, also should meet following formula:

D ₁≥30λ

Wherein λ is wavelength.

Again according to D ₁with half angle θ _mdetermine the focal distance f of speculum 44 ₁, specifically should meet formula as follows:

$p_1=\frac{2f_1}{1+\cos ({\mathrm{\&theta;}}_0-{\mathrm{\&theta;}}_m)}$

$p_2=\frac{2f_1}{1+\cos ({\mathrm{\&theta;}}_0+{\mathrm{\&theta;}}_m)}$

D ₁＝(p ₂-p ₁)cosθ _m

P wherein ₁, p ₂for the light path of beam edge ripple 55 of speculum 44 and speculums.

G. design reflectivity mirror 33, and speculum 33 is 45 ° with x to angle, therefore according to speculum 44 bore D ₁, determine speculum 33 bore D ₂.

H. design reflectivity mirror 22, according to required equivalent feed lateral displacement d _u1, minute surface Displacement Estimation value and drive stroke d _x, determine the minute surface combined amplifier factor, then redesign speculum 22 focal distance f in conjunction with speculum 33 bores ₂and incident half angle θ _mo.

Minute surface combined amplifier factor-alpha is defined as follows:

$\mathrm{\&alpha;}=\frac{d_{u3}}{d_{u1}}\&ap;\frac{f_2{K}_1}{f_1{K}_2}\&ap;\frac{f_2}{f_1}<\frac{d_x}{d_{u1}}$

Make the bore D of speculum 22 ₃the same D that is of bore with speculum 44 ₁, and make the θ of speculum 22 ₀=pi/2.

Have:

D ₃＝4f ₂tanθ _mo

E. according to incident half angle θ _moand feed is apart from speculum one 1 distance L, determines speculum 1

Bore D ₄.

D ₄＞2Ltanθ _mo

Described speculum one 1 Mirror frame structure designs and the speculum one 1 mirror holder minute surfaces of step (4) drive the computational methods of required azimuth direction drive displacement to be:

Speculum one 1 Mirror frame structure methods for designing:

When azimuth direction error is pointed in compensation, required equivalent feed B ₁at x, to translation, according to mirror-reflection principle, need the virtual image O of feed ₁be x to translation, and the translation of the virtual image, need speculum 1 to do plane motion, comprise translation and rotation, in order to simplify driving action direction, design reflectivity mirror one 1 Mirror frame structures, this designs simplification driving type of action: this mirror holder is comprised of guide post and mirror holder 11, guide post is vertical with mirror holder 11, mirror holder 11 is positioned on guide post middle vertical plane, guide post divides three sections, epimere is connected with an axle spring respectively with hypomere with stage casing and stage casing, guaranteed that guide post can axial stretching, hypomere end points is connected with feed revolute pair 3 23, epimere end points makes it be positioned at feed virtual image place, and affixed ball 9, barycenter place, stage casing guide post is connected by revolute pair 2 22 with a connecting rod.Make the ball 9 of this mirror holder in horizontal concrete chute, and mirror holder barycenter place connecting rod is placed in horizontal bush, can guarantee that horizontal displacement is done in the virtual image of speculum 1 all the time, and mirror holder 11 is positioned on the perpendicular bisector of feed and the virtual image all the time.Mirror holder is secondary by two groups of translations, guaranteed that mirror barycenter and mirror holder one end position only do translational motion all the time, two axle springs have guaranteed that speculum 1 is positioned on the perpendicular bisector of mirror holder all the time, thereby make mirror holder end points be respectively feed position and virtual image position, therefore only one end need be fixed in to feed place, do the other end load driver power of translational motion.

And when compensation pitch orientation error, required equivalent feed B ₁at z, to translation, according to mirror-reflection principle, need the virtual image O of feed ₁be z to translation; Only level crossing need be rotated and can ignore the movement of the virtual image in xy plane around one end, think the virtual image at z to translation has occurred.Therefore designed mirror holder pitch orientation only needs mirror one end to be connected with mirror holder by revolute pair 1, other end load driver power, and drive end is connected with speculum one use revolute pair 4 24.

Azimuth direction drive displacement is calculated:

Because azimuth direction actuating force directly loads on virtual image position, so drive required displacement to be equal to the required displacement d of the virtual image _u3.

Step (5) described according to the required displacement of the pitch orientation feed virtual image, calculate speculum 1 and drive required displacement, calculate as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the pitch orientation that the interarea system variant that causes causes _maxe, and equivalent feed B ₁pitching face in z to displacement d _e1can produce error in pointing θ equally _e1, make θ _maxe+ θ _e1=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{e1}=\frac{{\mathrm{\&theta;}}_{\max e}\mathrm{Mf}}{K}$

Wherein f is primary reflection surface focal length, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

Speculum 1 drives required displacement computational methods:

Equivalence feed B ₁to B ₂z to displacement d _e1, can be by the picture F of its equivalent feed ₁move to F ₂z to displacement d _e2calculate gained:

d _e1＝d _e2

So F ₁to F ₂z to displacement d _e2lateral displacement for the parabolic focus of speculum 44, make focus generation lateral displacement, and the incident light of speculum 44 departs from its xy plane θ _eangle, due to θ _egenerally less, therefore do not consider the impact defocusing here.θ _ecomputational methods as follows:

${\mathrm{\&theta;}}_e=\frac{d_{e2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum 44, f ₁focal length for speculum 44.

So beams incident deflection angle theta of speculum 44 _e, need the reflected beam of speculum 22 also to produce accordingly and the deflection angle theta of xy plane _e; Identical with the parabola principle of speculum 44, there is z to displacement d in the focus of needed speculum 22 _e3, computational methods are as follows:

$d_{e3}=\frac{{\mathrm{\&theta;}}_e{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum 22, f ₂focal length for speculum 22.

The focus of speculum 22 is the virtual image of speculum 1, and speculum one 1 virtual image z are d to displacement _e3

If the bore of speculum 1 is D ₄, feed is L apart from the distance of speculum 1, by following formula, can be obtained, speculum 1 drives required displacement d _d:

d _d＝d _e3D ₄/2L

Below in conjunction with concrete accompanying drawing, the present invention is described in further detail:

First according to Cassegrain antenna interarea system configuration, antenna present position load condition and desired operating mode, estimate the distortion that external applied load causes interarea system, and according to the error in pointing scope of interarea system variant (mainly comprising primary reflection surface distortion and 8 distortion of the interarea system breadth) antenna that estimation causes thus; Secondly, for error in pointing scope, calculate the displacement of required equivalent feed position; According to the driving stroke capability of position changeable speculum, design the size of each speculum, the required displacement of feed zooms in or out, and meets and drives stroke.

First the first step: calculate the required lateral displacement in equivalent feed position.As shown in Fig. 2 antenna interarea system vertical view, according to antenna institute wind-engaging, disturb situation, according to look-up table, estimate to be disturbed by wind the maximum error in pointing θ of the azimuth direction that the interarea system variant that causes causes _max, and equivalent feed B ₁lateral displacement d _u1can produce error in pointing θ equally ₁, make θ _max+ θ ₁=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{u1}=\frac{{\mathrm{\&theta;}}_{\max }\mathrm{Mf}}{K}$

Wherein f is primary reflection surface focal length, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

Second step: utilize the required displacement of minute surface according to a preliminary estimate of designed arrangement of mirrors.What in the present invention, beam waveguide system adopted is dual paraboloid combination, specifically as shown in Figure 3.

As shown in Figure 3, what the beam waveguide system of antenna adopted is dual paraboloid combination, and it comprises three plane mirrors; Feed O, through speculum 1, speculum 22, speculum 33, speculum 44 and speculum 55, obtains equivalent feed point B ₁, wherein speculum 1, speculum 33 and speculum 55 are followed successively by the level crossing more and more far away apart from feed 6, and speculum 22 and speculum 44 are paraboloidal mirror; Wherein speculum 44 can rotate with pitch axis.Speculum one 1 positions are movably used for changing equivalent feed B ₁position.Feed O, through speculum one, two, three, four and five reflections, obtains equivalent feed point B ₁if, by the virtual image O of feed O ₁move to O ₂, equivalent feed point B ₁also move to B ₂.Its O ₁to O ₂displacement d _u3circular is as follows:

Speculum 55 is θ with x to angle ₂, B ₁to B ₂x to displacement d _u1, can be by it as F ₁to F ₂y to displacement d _u2calculate gained:

d _u1＝d _u2×sin(180-2θ ₂)

The focal axis direction of speculum 44 is x direction, so F ₁to F ₂y to displacement d _u2for the lateral displacement of speculum 44 parabolic focus, make focus generation lateral displacement, the incident light of speculum 44 departs from its focal axis direction θ, because θ is generally less, does not therefore consider the impact defocusing here.The computational methods of θ are as follows:

$\mathrm{\&theta;}=\frac{d_{u2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum 44, f ₁focal length for speculum 44.

Speculum 33 is with x direction angle at 45 ° and maintain static, so the beams incident deflection angle theta of speculum 44, needs the reflected beam of speculum 22 also to produce corresponding deflection angle theta; Identical with speculum 44 parabola principles, needed speculum 22 focus generation lateral displacement d _u3, computational methods are as follows:

$d_{u3}=\frac{\mathrm{\&theta;}{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum 22, f ₂focal length for speculum 22.

The 3rd step: according to required d _u1, and drive stroke d _x(d _x> d _u3), design minute surface size, design procedure is as follows:

I. design reflectivity mirror 55 and x are to angle theta ₂between 45 ° to 55 °, guaranteed like this F ₁to F ₂y to displacement, can't produce larger B ₁to B ₂y to displacement, and affect the gain of interarea system electrical property.

J. design reflectivity mirror 44, determine bore D ₁and focal distance f ₁, as shown in Figure 4:

After primary reflection surface system is determined, wave beam half angle θ _malso determine; Speculum 55 and x are to angle theta ₂after determining, for guarantee wave beam vertically towards y to, speculum 44 reflected beam and x are to angle theta ₀also determine bore D ₁except the restriction of structure full-size, in order to reduce edge leakage, penetrate and diffraction phenomenon, also should meet following formula:

D ₁≥30λ

Again according to D ₁with half angle θ _mdetermine the focal distance f of speculum 44 ₁, specifically should meet formula as follows:

$p_1=\frac{2f_1}{1+\cos ({\mathrm{\&theta;}}_0-{\mathrm{\&theta;}}_m)}$

$p_2=\frac{2f_1}{1+\cos ({\mathrm{\&theta;}}_0+{\mathrm{\&theta;}}_m)}$

D ₁＝(p ₂-p ₁)cosθ _m

K. design reflectivity mirror 33, and speculum 33 is 45 ° with x to angle, therefore according to speculum

44 bore D ₁, determine speculum 33 bore D ₂.

L. design reflectivity mirror 22, according to required equivalent feed lateral displacement d _u1, minute surface is estimated displacement d _u3and driving stroke d _x, determine the minute surface combined amplifier factor, then redesign speculum 22 focal distance f in conjunction with speculum 33 bores ₂and incident half angle θ _mo.

Minute surface combined amplifier factor-alpha is defined as follows:

$\mathrm{\&alpha;}=\frac{d_{u3}}{d_{u1}}\&ap;\frac{f_2{K}_1}{f_1{K}_2}\&ap;\frac{f_2}{f_1}<\frac{d_x}{d_{u1}}$

Make the bore D of speculum 22 ₃be D the same as speculum 44 bores ₁, and make the θ of speculum 22 ₀=pi/2.

Have:

D ₃＝4f ₂tanθ _mo

M. according to incident half angle θ _moand feed is apart from speculum one 1 distance L, determines speculum one 1 bore D ₄.

D ₄＞2Ltanθ _mo

The 4th step: calculate compensation azimuth direction error in pointing, drive required displacement.Movable plane mirror one 1 structure vertical views as shown in Figure 5.

As shown in Figure 5, ball 9, the first axle spring 10, mirror holder 11, the second axle spring 12 are connected by first connecting rod 17, second connecting rod 18 and third connecting rod 19 on same member mirror holder, third connecting rod 19 is connected by revolute pair 3 23 with feed 6, translation axis of traction 15 is connected by revolute pair 2 22 with second connecting rod 18, drive electric cylinder 1 can drive ball 9 translation in the secondary chute 16 of translation, translation axis of traction 15 also can translation in translation secondary case cylinder 14, drives electric cylinder 1, translation secondary case cylinder 14 affixed with ground.Speculum 1 is connected with mirror holder 11, and connected mode is as shown in Fig. 6 (speculum one side view orientation).

As shown in Figure 6, mirror holder 11 is connected by revolute pair 1 with speculum one 1 tops, drives electric cylinder 2 20 and mirror holder 11 affixed, is connected by revolute pair 4 24 with speculum 1.

By speculum one 1 structures, can be found out, if ball 9 is positioned at the virtual image O of feed 6 ₁place, and mirror is positioned on whole mirror holder perpendicular bisector, now when driving electric cylinder 1 to drive ball 9 translation in horizontal concrete chute, virtual image O ₁do horizontal movement, work as O ₁horizontal displacement be d _u3time, azimuth direction error in pointing can be compensated.Virtual image O ₁displacement be to drive electric cylinder 1 to drive required displacement.

The 5th step: disturb situation according to antenna institute wind-engaging, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the pitch orientation that the interarea system variant that causes causes _maxe, and equivalent feed B ₁pitching face in z to displacement d _e1can produce error in pointing θ equally _e1, make θ _maxe+ θ _e1=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

$d_{e1}=\frac{{\mathrm{\&theta;}}_{\max e}\mathrm{Mf}}{K}$

Wherein f is interarea system primary reflection surface 7 focal lengths, and M is interarea system amplification factor, and K is primary reflection surface wave beam deflection factor, it to the burnt footpath of primary reflection surface than relevant.

Speculum 1 drives required displacement computational methods:

Equivalence feed B ₁to B ₂z to displacement d _e1, can be by the picture F of its equivalent feed ₁move to F ₂z to displacement d _e2calculate gained:

d _e1＝d _e2

So F ₁to F ₂z to displacement d _e2lateral displacement for the parabolic focus of speculum 44, make focus generation lateral displacement, and the incident light of speculum 44 departs from its xy plane θ _eangle, due to θ _egenerally less, therefore do not consider the impact defocusing here.θ _ecomputational methods as follows:

${\mathrm{\&theta;}}_e=\frac{d_{e2}{K}_1}{f_1}$

K wherein ₁for the wave beam deflection factor of speculum 44, f ₁focal length for speculum 44.

So beams incident deflection angle theta of speculum 44 _e, need the reflected beam of speculum 22 also to produce accordingly and the deflection angle theta of xy plane _e; Identical with the parabola principle of speculum 44, there is z to displacement d in the focus of needed speculum 22 _e3, computational methods are as follows:

$d_{e3}=\frac{{\mathrm{\&theta;}}_e{f}_2}{K_2}$

K wherein ₂for the wave beam deflection factor of speculum 22, f ₂focal length for speculum 22.

The focus of speculum 22 is the virtual image of speculum 1, and speculum one 1 virtual image z are d to displacement _e3

If the bore of speculum 1 is D ₄, feed 6 is L apart from the distance of speculum 1, as shown in Figure 7; By following formula, can be obtained, speculum 1 drives required displacement d _d:

d _d＝d _e3D ₄/2L

The present invention adopts the real-time adjustable method of the mirror position in beam waveguide system, change equivalent feed position in interarea system, thereby compensation is disturbed the interarea system variant causing and the antenna direction deviation causing by wind, has improved the pointing accuracy of antenna.

This method advantage:

1) from the structure of large-scale beam waveguide antenna, utilize real-time change reflector position to compensate by wind and disturb caused error in pointing, design the suitable minute surface combined amplifier factor and can greatly reduce the required displacement of driving, in the real-time of compensation, can be guaranteed.

2) structural design of unique adjustable speculum one mirror holder, making only needs axially to drive with simple, can realize speculum one and do plane motion (comprising translation and rotation), has avoided complicated type of drive, more convenient and practical.

The part that the present embodiment does not describe in detail belongs to the known conventional means of the industry, here not narration one by one.More than exemplifying is only to illustrate of the present invention, does not form the restriction to protection scope of the present invention, within the every and same or analogous design of the present invention all belongs to protection scope of the present invention.

Claims (6)

1. an error in pointing compensation method for large-scale beam waveguide antenna wind disturbance resistance, is characterized in that: comprise the steps:

(1) calculate the required lateral displacement in equivalent feed position;

(2) determine the arrangement of mirrors structure of the beam waveguide system of antenna, utilize the required displacement of feed virtual image minute surface according to a preliminary estimate of this arrangement of mirrors structure;

Determined arrangement of mirrors is dual paraboloid combination, and it comprises three plane mirrors; Feed (6) O, through speculum one (1), speculum two (2), speculum three (3), speculum four (4) and speculum five (5), obtains equivalent feed point B ₁, wherein speculum one (1), speculum three (3) and speculum five (5) are followed successively by apart from feed (6) level crossing more and more far away, and speculum two (2) and speculum four (4) they are paraboloidal mirror; For the speculum four (4) of paraboloidal mirror can rotate with pitch axis, guaranteed that equivalent feed position rotates and change luffing angle with pitch axis; Adjustable in real time for speculum one (1) position of level crossing, be used for changing the real time position of equivalent feed, if by the virtual image O of feed (6) O ₁move to O ₂, equivalent feed point B ₁also move to B ₂;

(3), according to the stroke of the required minute surface displacement of the feed virtual image and driver, specifically determine each mirror mirror size;

(4) determine the structure of speculum one (1), according to the required displacement of the azimuth direction feed virtual image, calculate speculum one (1) azimuth direction and drive required displacement;

(5), according to the required displacement of the pitch orientation feed virtual image, calculate speculum one (1) pitch orientation and drive required displacement.

2. the error in pointing compensation method of a kind of large-scale beam waveguide antenna wind disturbance resistance according to claim 1, is characterized in that: the computational methods of the lateral displacement that the described equivalent feed position of step (1) is required are carried out as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the azimuth direction that the interarea system variant that causes causes _max, and equivalent feed B ₁lateral displacement d _u1can produce error in pointing θ equally ₁, make θ _max+ θ ₁=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

Wherein f is interarea system primary reflection surface (7) focal length, and M is interarea system amplification factor, and K is interarea system primary reflection surface (7) wave beam deflection factor, it to the burnt footpath of interarea system primary reflection surface (7) than relevant.

3. the error in pointing compensation method of a kind of large-scale beam waveguide antenna wind disturbance resistance according to claim 1, is characterized in that: the computational methods of the required displacement of minute surface according to a preliminary estimate that step (2) is described are:

The required displacement estimation method of minute surface:

If speculum five (5) is θ with x to angle ₂, equivalent feed B ₁to B ₂x to displacement d _u1, can be by the picture F of its equivalent feed ₁move to F ₂y to displacement d _u2calculate gained:

d _u1＝d _u2×sin(180-2θ ₂)

And the focal axis direction of speculum four (4) is x direction, so F ₁to F ₂y to displacement d _u2lateral displacement for the parabolic focus of speculum four (4), make focus generation lateral displacement, the incident light of speculum four (4) need depart from angle θ of x direction, this angle θ is the beams incident deflection angle of speculum four (4), because θ is generally less, therefore do not consider the impact defocusing here, the computational methods of θ are as follows:

K wherein ₁for the wave beam deflection factor of speculum four (4), f ₁focal length for speculum four (4);

Speculum three (3) is with x direction angle at 45 ° and maintain static; According to the refraction principle of light, therefore the beams incident deflection angle theta of speculum four (4) is the reflected beam deflection angle of speculum three (3), and the reflected beam that needs speculum two (2) is the deflection angle theta that the incident wave beam of speculum three (3) also produces corresponding size; Identical with the parabola principle of speculum four (4), the focus generation lateral displacement d of needed speculum two (2) _u3, computational methods are as follows:

K wherein ₂for the wave beam deflection factor of speculum two (2), f ₂focal length for speculum two (2).

Get: K ₁=K ₂, f ₁=f ₂,

D _u3for minute surface Displacement Estimation value.

4. the error in pointing compensation method of a kind of large-scale beam waveguide antenna wind disturbance resistance according to claim 1, is characterized in that: the concrete steps of described step (3) are as follows:

A. design reflectivity mirror five (5) and x are to angle theta ₂between 45 ° to 55 °, guaranteed like this F ₁to F ₂y to displacement, can't produce larger B ₁to B ₂y to displacement, and affect the gain of interarea system electrical property;

B. design reflectivity mirror four (4), determine bore D ₁and focal distance f ₁:

After interarea system primary reflection surface (7) system is determined, wave beam half angle θ _malso determine; Speculum five (5) and x are to angle theta ₂after determining, for guarantee wave beam vertically towards y to, speculum four (4) reflected beam axis and x are to angle theta ₀also determine bore D ₁except the restriction of structure full-size, in order to reduce edge leakage, penetrate and diffraction phenomenon, also should meet following formula:

D ₁≥30λ

Wherein λ is wavelength;

Again according to D ₁with half angle θ _mdetermine the focal distance f of speculum four (4) ₁, specifically should meet formula as follows:

D ₁＝(p ₂-p ₁)cosθ _m

P wherein ₁, p ₂for the light path of beam edge ripple between speculum four (4) and speculum five (5).

C. design reflectivity mirror three (3), and speculum three (3) is 45 ° with x to angle, therefore according to speculum four (4) bore D ₁, determine speculum three (3) bore D ₂;

D. design reflectivity mirror two (2), according to required equivalent feed lateral displacement d _u1, minute surface Displacement Estimation value and drive stroke d _x, determine the minute surface combined amplifier factor, then redefine speculum two (2) focal distance f in conjunction with speculum three (3) bores ₂and incident half angle θ _mo;

Minute surface combined amplifier factor-alpha is defined as follows:

Make the bore D of speculum two (2) ₃the same D that is of bore with speculum four (4) ₁, and make speculum two (2) θ ₀=pi/2;

Have: D ₃=4f ₂tan θ _mo

E. according to incident half angle θ _moand feed is apart from speculum one (1) distance L, determines speculum one (1) bore D4, D ₄> 2Ltan θ _mo.

5. the error in pointing compensation method of a kind of large-scale beam waveguide antenna wind disturbance resistance according to claim 1, is characterized in that: described speculum one (1) Mirror frame structure design and speculum one (1) the mirror holder minute surface of step (4) drives the computational methods of required azimuth direction drive displacement to be:

Speculum one (1) Mirror frame structure method for designing:

When azimuth direction error is pointed in compensation, required equivalent feed B ₁at x, to translation, according to mirror-reflection principle, need the virtual image O of feed (6) ₁be x to translation, and the translation of the virtual image, need speculum one (1) to do plane motion, comprise translation and rotation, in order to simplify driving action direction, design reflectivity mirror one (1) Mirror frame structure, this designs simplification driving type of action: this mirror holder is comprised of guide post and mirror holder (11), guide post is vertical with mirror holder (11), mirror holder (11) is positioned on guide post middle vertical plane, guide post divides three sections, epimere is connected with an axle spring respectively with hypomere with stage casing and stage casing, guaranteed that guide post can axial stretching, hypomere end points is connected with feed (6) revolute pair three (23), epimere end points makes it be positioned at feed virtual image place, and affixed ball (9), barycenter place, stage casing guide post is connected by revolute pair two (22) with a connecting rod.Make the ball (9) of this mirror holder in horizontal concrete chute, and mirror holder barycenter place connecting rod is placed in horizontal bush, horizontal displacement is done in the virtual image that can guarantee speculum one (1) all the time, and mirror holder (11) is positioned on the perpendicular bisector of feed (6) and the virtual image all the time.Mirror holder is secondary by two groups of translations, guaranteed that mirror barycenter and mirror holder one end position only do translational motion all the time, two axle springs have guaranteed that speculum one (1) is positioned on the perpendicular bisector of mirror holder all the time, thereby make mirror holder end points be respectively feed (6) position and virtual image position, therefore only one end need be fixed in to feed (6) and locate, do the other end load driver power of translational motion.

And when compensation pitch orientation error, required equivalent feed B ₁at z, to translation, according to mirror-reflection principle, need the virtual image O of feed (6) ₁be z to translation; Only level crossing need be rotated and can ignore the movement of the virtual image in xy plane around one end, think the virtual image at z to translation has occurred.Therefore designed mirror holder pitch orientation only needs mirror one end to be connected with mirror holder by revolute, other end load driver power;

Azimuth direction drive displacement is calculated:

Because azimuth direction actuating force directly loads on virtual image position, so drive required displacement to be equal to the required displacement d of the virtual image _u3.

6. the error in pointing compensation method of a kind of large-scale beam waveguide antenna wind disturbance resistance according to claim 1, it is characterized in that: step (5) described according to the required displacement of the pitch orientation feed virtual image, calculate speculum one (1) and drive required displacement, calculate as follows:

According to antenna institute wind-engaging, disturb situation, application look-up table estimates to be disturbed by wind the maximum error in pointing θ of the pitch orientation that the interarea system variant that causes causes _maxe, and equivalent feed B ₁pitching face in z to displacement d _e1can produce error in pointing θ equally _e1, make θ _maxe+ θ _e1=0, can obtain the required maximum transversal displacement d in equivalent feed position _u1:

Wherein f is interarea system primary reflection surface (7) focal length, and M is interarea system amplification factor, and K is interarea system primary reflection surface (7) wave beam deflection factor, it to the burnt footpath of interarea system primary reflection surface (7) than relevant.

Speculum one (1) drives required displacement computational methods:

Equivalence feed B ₁to B ₂z to displacement d _e1, can be by the picture F of its equivalent feed ₁move to F ₂z to displacement d _e2calculate gained:

d _e1＝d _e2

So F ₁to F ₂z to displacement d _e2lateral displacement for the parabolic focus of speculum four (4), make focus generation lateral displacement, and the incident light of speculum four (4) departs from its xy plane θ _eangle, due to θ _egenerally less, therefore do not consider the impact defocusing here.θ _ecomputational methods as follows:

K wherein ₁for the wave beam deflection factor of speculum four (4), f ₁focal length for speculum four (4).

So beams incident deflection angle theta of speculum four (4) _e, need the reflected beam of speculum two (2) also to produce accordingly and the deflection angle theta of xy plane _e; Identical with the parabola principle of speculum four (4), there is z to displacement d in the focus of needed speculum two (2) _e3, computational methods are as follows:

K wherein ₂for the wave beam deflection factor of speculum two (2), f ₂focal length for speculum two (2).

The focus of speculum two (2) is the virtual image of speculum one (1), and speculum one (1) virtual image z is d to displacement _e3

If the bore of speculum one (1) is D ₄, feed (6) is L apart from the distance of speculum one (1), by following formula, can be obtained, speculum one (1) drives required displacement d _d:

d _d＝d _e3D ₄/2L?。