CN103727919B - A kind of stationary orbit geostationary satellite numeral method for searching star - Google Patents

Abstract

The present invention relates to stationary orbit geostationary satellite technical field, specifically disclose a kind of stationary orbit geostationary satellite numeral method for searching star; Including: directly gather topocentric positional information by GPS or Big Dipper terminal unit; By inputting the parameter of topocentric positional information based on the call instruction of http agreement; By specify topocentric position processing module, spheroid auxiliary variable computing module, specify ground point to specified satellite sighting distance processing module, specify ground point to the elevation angle processing module of specified satellite and to specify ground point to the true north azimuth processing module of specified satellite to be calculated; Calculate arbitrfary point, ground to the sighting distance L of satellite, arbitrfary point, ground to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite, changed by data conversion module and star result is sought in display in human-computer interaction interface, establish the relative position of ground point and satellite by seeking star result. Theory of the present invention is rigorous, and method for searching star is efficient; Calculation result accuracy is high.

Description

A kind of stationary orbit geostationary satellite numeral method for searching star

Technical field

The present invention relates to stationary orbit geostationary satellite technical field, especially relate to a kind of geologic survey in the wild realizes, by stationary orbit geostationary satellite, the method that numeral seeks star.

Background technology

Beidou satellite navigation system space segment is made up of 5 stationary orbits and 30 non-geo satellites, wherein, 5 geostationary satellites (Beidou-G4, G1, G3, G6, G5 of Fig. 1) being arranged in stationary orbit have short message communication, initial location and time service service three zones, the each frequency of its short message communication transmits up to 77 effective bytes, horizontal positioning accuracy is generally about 100m, and satellite height off the ground is about 35766922m. The location of big-dipper satellite and mechanics of communication are in the popularization and application stage in the Asian-Pacific area, its short message communication function can for adopting the outdoor moving equipment of Big Dipper technology, monitoring equipment or field man to provide note to broadcast service, especially for mobile phone signal blind area or without the area (such as western depopulated zone, high altitude localities etc.) in other communication conditions (such as satellite phone, transmitter receiver, radio station etc.), vital effect can be played in life security guarantee, producer goods scheduling, the management of personnel's situation, routine work communication etc.

It is positioned at the big-dipper satellite optimum signal intensity of stationary orbit for making ground communications terminal unit to get, need to guarantee that reception equipment is in satellite communication ken window ranges and by the orientation determined, correct inclination angle and the shortest sighting distance directly to certain satellite.

The Big Dipper is received equipment (or antenna) and adjusts roughly by the mode all taking visual estimation on the spot in routine work, and usual guiding spoken language has:

Where is satellite?-in the south!

Where can be regarded as the south?-see the sun!

Can signal be received? could not there be shelter-the south!

How high is shelter? how far?-antenna tilts about 40 degree to the south and does not find to block just!

Staff can only judge the power of communication state and signal with the signal lattice value size in equipment display window, cause satellite position to be difficult to determine, antenna puts that (place, orientation, the elevation angle) randomness is big, communication visible range scope cannot be predicted, when especially using terminal in Canyon Area, very easily cause downstream signal to receive because massif blocks, upward signal cannot send (or claiming blind spot), has had a strong impact on normally carrying out of work.

Prior art not yet relates to stationary orbit Big Dipper numeral and seeks star, only for being in stationary orbit geostationary satellite (such as Asiasat 1, Asia two, the broadcast satellites such as STAT-2), though once addressing the elevation angle of ground receiving equipment and azimuthal reckoning problem, through consulting related data, calculation method model also relates to seek star parameter (azimuth, the elevation angle) calculating aspect, the technology that existing method for searching star is commonly used to duplicate with satellite simple geometric relationships with Fig. 2 earth, reckoning process is substantially decomposed into azimuthal angle calculation and the elevation angle calculates two steps:

In formula, ��: ground point to satellite through difference;Topocentric latitude; ��: ground point, satellite and the subtended angle that is formed centrally.

Study by analysis, in the shortcoming that techniqueflow involved by prior art and method for searching star exist in reckoning process includes following four:

Earth coordinates should with simple spherosome for reference frame, and the method for searching star thus set up lacks strict theoretical basis and mathematical model, and the result calculated is very rough and without practical value;

The calculating chosen is selected A and is not represented at random cake, and described ground point should not be placed on spherome surface, it is necessary to consider the impact of height above sea level;

The calculating point A chosen and satellite B not should be within same meridian plane, and this not only limit the arbitrariness that ground point is chosen, and this point is not representative;

The elevation angle calculates and with the tangent line of A excessively for benchmark, should should not be based upon on triaxial ellipsoid incisal plane or horizontal plane.

Obviously, seeking star although existing to control the resolving model inference process of parameter simple, but theoretical basis exists (incorrect or imprecision) problem, topocentric method for searching star and practical situation are not inconsistent, and in real work, available value is little.

At present, Beidou navigation satellite (communication and location) technology formally puts into civilian in the Asian-Pacific area, for solving putting of stationary orbit Beidou satellite communication terminal unit and have blindness, seeking star and have randomness, the delineation of signal visible range has artificial property, thus wheresoever answering certain satellite rapidly and accurately? is which satellite from us recently (signal is best)? which satellite will not be blocked problems such as (not in blind area) by barrier above, set up accurately, science, efficient method for searching star seem very necessary and urgent.

Summary of the invention

Technical problem solved by the invention is to provide a kind of stationary orbit geostationary satellite numeral method for searching star, stationary orbit Geo-synchronous big-dipper satellite numeral method for searching star of the present invention, Main Basis astrophysics and riemannian geometry, provide REST (the declarative state transfer) calling interface based on HTTP (HTML (Hypertext Markup Language)), the elevation angle to satellite, the arbitrfary point, far call quick obtaining ground can be passed through, the quantized value of true north azimuth and sighting distance etc. " numeral seeks star " parameter, being disposed and used of Big Dipper terminal unit can effectively play the effect of " compass ", thus the arrangement solving Beidou satellite communication terminal unit is put and is had randomness, the differentiation delineation of signal visible range has the problems such as artificial property.

In order to solve above-mentioned technical problem, the invention provides a kind of stationary orbit geostationary satellite numeral method for searching star, including:

S1: directly gather topocentric positional information by GPS or Big Dipper terminal unit;By inputting the parameter of described topocentric positional information based on the call instruction of http agreement;

S2: according to semimajor axis of ellipsoid a and semi-minor axis b and topocentric latitudeBy specify topocentric position processing module calculate ground point along normal direction at the subpoint of ellipsoid to the distance r in the earth's core;

S3: according to ellipsoidal parameter a and b and ground point latitudeThe satellite beeline to equatorial line is calculated by spheroid auxiliary variable computing module;

The angle of topocentric normal and the equatoriat plane is calculated by spheroid auxiliary variable computing module;

By spheroid auxiliary variable computing module calculating ellipsoid subpoint to the distance between described topocentric incisal plane and meridian plane intersection point;

Incisal plane and meridian plane intersection point is calculated to the distance between ground point normal and equatoriat plane intersection point by spheroid auxiliary variable computing module;

S4: by specifying ground point to calculate the distance between ground point normal and equatoriat plane intersection point and satellite to the sighting distance processing module of specified satellite; By specifying the angle of the ground point elevation angle processing module calculating ground point normal section to specified satellite and equatoriat plane intersection; By specifying ground point to calculate satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point to the true north azimuth processing module of specified satellite;

S5: by data conversion module be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground according to calculating arbitrfary point, ground in described step S3 and described step S4;

S6: seek star result described in display in human-computer interaction interface, described in seek star result and include sighting distance L, elevation angle �� and true north azimuth ��, establish the relative position of described ground point and satellite by described star result of seeking.

Preferably, in described step S1, the call instruction based on http agreement adopts the stipulated form of declarative state transfer interface to carry out; Described GPS or Big Dipper terminal unit include Tian Bao GPS terminal receiver, collection thinks precious hand-held set, Big Dipper terminal module, iphone4S mobile phone and Samsung S4 mobile phone.

More preferably, in described step S1, described topocentric positional information includes satellite longitude, ground point longitude, ground point latitude and ground point elevation.

More preferably, described satellite longitude is appointed as the longitude of certain stationary orbit Geo-synchronous big-dipper satellite, and described longitude includes 160 ��, 140 ��, 110.5 ��, 80 �� or 58.75 ��; The described 160 �� of corresponding stationary orbit Big Dipper-G4 satellites, the described 140 �� of corresponding stationary orbit Big Dipper-G1 satellites, the described 110.5 �� of corresponding stationary orbit Big Dipper-G3 satellites, the described 80 �� of corresponding stationary orbit Big Dipper-G6 satellites, the described 58.75 �� of corresponding stationary orbit Big Dipper-G5 satellites.

More preferably, described ground point longitude, described ground point latitude and described ground point elevation are directly measured by the terminal unit with GPS function.

More preferably, in described step S2, the topocentric positional information of input is converted to the topocentric positional information of Circular measure by described appointment topocentric position processing module, and the topocentric positional information calculation according to Circular measure goes out the described ground point p distance r at the subpoint e to the earth's core o of ellipsoid; Computing formula is:

Wherein, the latitude value of ground point p isSemimajor axis of ellipsoid is a, and semiminor axis of ellipsoid is b.

More preferably, in described step S3, first described spheroid auxiliary variable computing module calculates the satellite s minimum distance H to equatorial line, and computing formula is as follows:

By earth Near Earth Orbit Satellites speed v, orbit radius a is semimajor axis of ellipsoid, and the orbital period is T, calculates centripetal force by gravitation, and formula is:

$G\left(\frac{mM}{a^2}\right)=m\left(\frac{v^2}{a}\right);$

For stationary orbit geostationary satellite, still pressing gravitation and calculate centripetal force, formula is:

$G\left(\frac{mM}{{(a+H)}^2}\right)=m(a+H){\left(\frac{2\mathrm{\π}}{T}\right)}^2;$

In formula, G is universal gravitational constant, and m is near-earth satellite quality, and M is earth quality, then can release:

$H=\sqrt[3]{\frac{{\mathrm{av}}^2{T}^2}{4{\mathrm{\π}}^2}}-a\≈35766922m;$

Then the normal of ground point p and the angle of the equatoriat plane are calculated, ground point p along normal direction at the subpoint e of ellipsoid to the distance of the equatoriat plane and the earth's core o, ellipsoid subpoint e is to distance between described topocentric incisal plane and meridian plane intersection point t, incisal plane and meridian plane intersection point t are to the distance between ground point normal and equatoriat plane intersection point g, distance between ground point normal and equatoriat plane intersection point g and satellite s, the angle of ground point normal section and equatoriat plane intersection and satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point g,

If setting the earth's core as o, the line of ground point p and satellite s is ps, and ground point p is g along the intersection point of normal direction Yu the equatoriat plane, and the angle between line segment sp and line segment sg is ��; Angle between line segment gp and line segment gs is ��, and the latitude value of ground point p isThe longitude of ground point p is ��, and the height value of ground point p is h, and the longitude of satellite S is ��, and ground point p projection is e to the point on ellipsoid, the implicit function at some e place be F (x, y, z), calculating process is as follows:

$F(x,y,z)=\frac{x^2}{a^2}+\frac{y^2}{a^2}+\frac{z^2}{b^2}-1;$

X, y, z is asked partial derivative respectively, and the tangent equation at invocation point e place is:

$\frac{2x_e}{a^2}(x-x_e)+\frac{2y_e}{a^2}(y-y_e)+\frac{2z_e}{b^2}(z-z_e)=0,$

Draw the normal line vector in incisal plane

If setting up an office, the normal section at the e place meridian plane with the intersection of the equatoriat plane and with e point excessively intersects at t point, then vectorAccording toWithThe inner product formula of two vectors, can try to achieve the angle between two vectors:

Or

In the triangle being made up of e, g and o, can draw by sine:

Again because of vector $\stackrel{\→}{og}=\{og*cos\mathrm{\λ},og*\sin \mathrm{\λ},0\}$ And vector $\stackrel{\→}{os}=\{(a+h)cos\mathrm{\ω},(a+$ $h)\sin \mathrm{\ω},0\};$

Then vector $\stackrel{\→}{gs}=\stackrel{\→}{os}-\stackrel{\→}{og}=\{(a+h)cos\mathrm{\ω}-og*cos\mathrm{\λ},(a+h)\sin \mathrm{\ω}-og*$ $\sin \mathrm{\λ},0\};$

Vector simultaneously

In right angled triangle �� egt, utilize trigonometric function relational expression can obtain line segment et and the length of line segment gt, be respectively as follows:

In triangle �� ogs, the cosine law draw:

ByWithThe direction cosines of two vectors draw:

In triangle �� pgs, sine draw:

$\mathrm{\δ}={\sin }^{-1}\left(\frac{eg+h}{\sqrt{{(h+eg)}^2+{\mathrm{gs}}^2-2*gs*(h+eg)cos\mathrm{\θ}}}sin\mathrm{\θ}\right).$

More preferably, in described step S3, when ground point p overlaps with equatorial line, described distance r is equal to semimajor axis of ellipsoid a; When ground point is in a plane together with satellite, the earth's core and rotating shaft, the angle that line segment go and line segment gs is formed is 180 ��.

More preferably, in described step S4, described appointment ground point to specified satellite stadia computation module by described step S3 obtain intermediate variable, the arbitrfary point, the ground sighting distance L to satellite is asked for the spatial triangle that equatoriat plane intersection point forms by the cosine law for by ground point, satellite and topocentric normal, and press the angle sum of a triangle principle equal to 180 degree, asking for the arbitrfary point, the ground elevation angle �� to satellite, computing formula is:

When �¡�0, described ground point is considered as absolute blind spot; As �� > 0 time, if there being barrier to block between ground point and satellite links, described ground point is then considered as relative blind spot; Described absolute blind spot refer to because of earth bending cause cannot the ground point of communication, described relative blind spot refers to that cause cannot the ground point of communication because massif blocks;

Described appointment ground point to specified satellite true north azimuth computing module described in the intermediate variable that obtains in step S3, in topocentric normal section, space right-angle triangle is collectively constituted by described normal section and the intersection point of earth axis and this normal section and the equatoriat plane and two intersection points that intersect through topocentric meridian plane, asking for the arbitrfary point, the ground true north azimuth �� to satellite by antitrigonometric function relation, computing formula is:

$\mathrm{\α}=\mathrm{\π}\±{\tan }^{-1}(\frac{gt}{et}*tan(\mathrm{\π}-{\cos }^{-1}\left(\frac{{\mathrm{og}}^2+{\mathrm{gs}}^2-{(a+H)}^2}{2*og*gs}\right)\left)\right);$

In formula described �� symbol, take as ��-�� > 0 positive sign+, take when ��-�ء�0 negative sign-;

Wherein, the latitude value of ground point p isThe longitude of ground point p is ��, and the height value of ground point p is h, and the longitude of satellite S is ��.

More preferably, in described step S5, described data conversion module is by data conversion module to be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground by calculating arbitrfary point, ground.

Wherein, described stationary orbit geostationary satellite is domestic Beidou location and communications satellite, is now made up of five satellites of Beidou-G4, G1, G3, G6, G5.

Wherein, described ground point is arbitrfary point, earth's surface, longitude, latitude, elevation three parameter determine.

Wherein, described true north azimuth be ground point from earth axis along clockwise direction to the angle of certain satellite.

Wherein, the described elevation angle is ground point to the angle between the line and horizontal plane of certain satellite.

Wherein, described sighting distance is the ground point distance to certain satellite.

Wherein, described blind area is that communication data packets cannot receive or receive incomplete region.

Wherein, described inner product is also referred to as scalar product or dot product.

Wherein, described GPS is the abbreviation of English GlobalPositioningSystem (global positioning system). GPS originates in a project of US military in 1958, within 1964, comes into operation. 20 century 70s, land, sea, and air of U.S. joint research and developments Global Positioning System of new generation. Main purpose is to provide real-time, round-the-clock and global navigation Service for big field, land, sea and air three, and for some military purposes such as information acquisition, Nuclear detonation monitoring and emergency communications, research experiment through more than 20 years, cost 30,000,000,000 dollars, by 1994, the Global coverage rate 24 gps satellite constellations up to 98% are own to be laid.

Wherein, described JSON (JavaScriptObjectNotation) is the data interchange format of a kind of lightweight. It is based on a subset of JavaScript (StandardECMA-2623rdEdition-December1999). JSON adopts the text formatting being totally independent of language, but also using the custom (including C, C++, C#, Java, JavaScript, Perl, Python etc.) being similar to C language family. These characteristics make JSON become desirable data interchange language. It is prone to people read and write, is also easy to machine simultaneously and resolves and generate.

Wherein, described XML is extensible markup language, is the subset of standard generalized markup language, is a kind of make it have structural markup language for labelling e-file. It can be used to flag data, definition data type, is the original language that is defined of a kind of user of permission markup language to oneself. It is especially suitable for WWW transmission, it is provided that unified method describes and exchange the structural data independent of application program or supplier.

The present invention compared with prior art, has the advantages that

The technology based on BeiDou-I satellite location with communication that the present invention carries out in the wild plays an important role in applying, the present invention is based on astrophysics and riemannian geometry rationale, formulate rigorous techniqueflow, establish tight resolving equation and have developed highly effective algorithm, the offset issue causing algorithm basis to exist is calculated: the ground point parameter set up account for Elevation factor on the basis of longitude and latitude, tallies with the actual situation by adopting general ellipsoid reference frame to solve rule spheroid; Ground point can be at optional position, earth's surface (within satellite view scope), without being maintained in same meridian plane with satellite; The elevation angle calculates the datum level relied on and have passed through the calculating of xyz three-dimensional partial derivative, and the datum level drawn is topocentric incisal plane, not with simple tangent line for benchmark. Thus achieve stationary orbit big-dipper satellite numeral and seek star and parameter calculation technology.

Does the invention solves putting of stationary orbit Beidou satellite communication terminal unit and have blindness, seek star and have randomness, the delineation of signal visible range have artificial property, thus wheresoever answering certain satellite rapidly and accurately? is which satellite from us recently (signal is best)?Which satellite will not be blocked problems such as (not in blind area) by barrier above, set up accurately, science, efficient method for searching star seem very necessary and urgent, of the present invention and core technology will necessarily based on big-dipper satellite application play highly important effect.

The theoretical basis that the present invention adopts is more rigorous, and method for searching star is more efficient; The accuracy of calculation result has passed through Ministry of Land and Resources's industry scientific research special item (fund project: the field geological work based on 3S technology manages and service key technical research and application, No.201011010), many field tests that China northeast, northwest, section, southwest are carried out obtain extensive checking, achieves gratifying technique effect. Wheresoever the present invention answers certain " stationary orbit big-dipper satellite " accurately, and which satellite is nearest from us, and which satellite will not by problems such as barrier above block. The present invention can provide the decision-making and reference frame that quantify for the extensive use in the Asian-Pacific area of the stationary orbit Beidou satellite communication technology; How to put for ground communication equipment, how to avoid communication blind zone and provide effective means; May act as numeral to seek " micro-kernel " of star compass and be embedded in the terminal unit of hardware vendor; Corresponding algorithm can be worked out according to method for searching star and be dissolved in all multi-application system of big-dipper satellite; There is promotional value widely.

Accompanying drawing explanation

Exemplary the illustrating of Fig. 1 is positioned at the running orbit schematic diagram of five big-dipper satellites of stationary orbit;

What Fig. 2 was exemplary illustrates the simple geometric relationships schematic diagram of satellite and the earth;

What Fig. 3 was exemplary illustrates numeral method for searching star principle schematic of the present invention;

What Fig. 4 was exemplary illustrates the absolute blind area schematic diagram that the earth is bent to form;

What Fig. 5 was exemplary illustrates that massif blocks the relative blind area schematic diagram of formation;

What Fig. 6 was exemplary illustrates numeral method for searching star schematic flow sheet of the present invention.

Detailed description of the invention

For the technical scheme being better understood from technical problem solved by the invention, provide, below in conjunction with drawings and Examples, the present invention is further elaborated. Specific embodiment described herein is only in order to explain the enforcement of the present invention, but is not intended to limit the present invention.

In a preferred embodiment, what Fig. 3 and Fig. 6 was exemplary illustrates principle and the schematic flow sheet of a kind of stationary orbit geostationary satellite numeral method for searching star; The process of method for searching star includes:

N1: directly gather topocentric positional information by GPS or Big Dipper terminal unit; By inputting the parameter of described topocentric positional information based on the call instruction of http agreement;

N2: according to semimajor axis of ellipsoid a and semi-minor axis b and topocentric latitudeBy specifying topocentric position processing module to calculate the ground point subpoint at ellipsoid to the distance r in the earth's core;

N3: according to ellipsoidal parameter a and b and ground point latitudeThe satellite beeline to equatorial line is calculated by spheroid auxiliary variable computing module;

The angle of topocentric normal and the equatoriat plane is calculated by spheroid auxiliary variable computing module;

By spheroid auxiliary variable computing module calculating ellipsoid subpoint to the distance between described topocentric incisal plane and meridian plane intersection point;

Incisal plane and meridian plane intersection point is calculated to the distance between ground point normal and equatoriat plane intersection point by spheroid auxiliary variable computing module;

N4: by specifying ground point to calculate the distance between ground point normal and equatoriat plane intersection point and satellite to the sighting distance processing module of specified satellite;By specifying the angle of the ground point elevation angle processing module calculating ground point normal section to specified satellite and equatoriat plane intersection; By specifying ground point to calculate satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point to the true north azimuth processing module of specified satellite;

N5: by data conversion module be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground according to calculating arbitrfary point, ground in described step N4;

N6: seek star result as described in display in human-computer interaction interface (such as InternetExplorer web browser window), described star result of seeking includes sighting distance L, elevation angle �� and true north azimuth ��, establishes the relative position of described ground point and satellite by described star result of seeking.

In embodiment more preferably, in described step N1, the call instruction based on http agreement adopts the stipulated form of declarative state transfer interface to carry out. Does the present invention provide internet address and the access mode to be: http: // 219.144.130.58/GEOsitecoder/satellite? satellitelng=satellite Jing Du &lng=ground point Jing Du &lat=ground point Wei Du &elev=ground point Gao Cheng &format=0 or 1, wherein, the http access path of agreement is http: // 219.144.130.58/GEOsitecoder/satellite, and the known parameters that need to input during access is followed successively by:

Satellitelng=satellite longitude;

Lng=ground point longitude;

Lat=ground point latitude;

Elev=ground point elevation;

Format=specifies the output format seeking star result, it is intended that when being 0, object output string format; It is appointed as output label string format when 1.

In embodiment more preferably, in described step N1, described topocentric positional information includes satellite longitude, ground point longitude, ground point latitude and ground point elevation.

In embodiment more preferably, in described step N1, described GPS or Big Dipper terminal unit include Tian Bao GPS terminal receiver, collection thinks precious hand-held set, Big Dipper terminal module, iphone4S mobile phone and Samsung S4 mobile phone.

In embodiment more preferably, described satellite longitude is appointed as the longitude of certain stationary orbit Geo-synchronous big-dipper satellite, and described longitude includes 160 ��, 140 ��, 110.5 ��, 80 �� or 58.75 ��; The described 160 �� of corresponding stationary orbit Big Dipper-G4 satellites, the described 140 �� of corresponding stationary orbit Big Dipper-G1 satellites, the described 110.5 �� of corresponding stationary orbit Big Dipper-G3 satellites, the described 80 �� of corresponding stationary orbit Big Dipper-G6 satellites, the described 58.75 �� of corresponding stationary orbit Big Dipper-G5 satellites.

In embodiment more preferably, described ground point longitude, described ground point latitude and described ground point elevation are directly measured by the terminal unit with GPS.

In embodiment more preferably, in described step N2, the topocentric positional information (decimal scale angular unit) of input can be converted to the topocentric positional information of Circular measure by described appointment topocentric position processing module, and the topocentric positional information calculation according to Circular measure goes out the described ground point p distance r at the subpoint e to the earth's core o of ellipsoid; Computing formula is:

In embodiment more preferably, in described step N3, first described spheroid auxiliary variable computing module calculates the satellite s minimum distance H to equatorial line, and computing formula is as follows:

By earth Near Earth Orbit Satellites speed v, orbit radius a is semimajor axis of ellipsoid, and the orbital period is T, calculates centripetal force by gravitation, and formula is:

$G\left(\frac{mM}{a^2}\right)=m\left(\frac{v^2}{a}\right)$

For stationary orbit geostationary satellite, still pressing gravitation and calculate centripetal force, formula is:

$G\left(\frac{mM}{{(a+H)}^2}\right)=m(a+H){\left(\frac{2\mathrm{\π}}{T}\right)}^2$

In formula, G is universal gravitational constant, and m is near-earth satellite quality, and M is earth quality, then can release:

$H=\sqrt[3]{\frac{{\mathrm{av}}^2{T}^2}{4{\mathrm{\π}}^2}}-a\≈35766922m$

Then the normal of ground point p and the angle of the equatoriat plane are calculated, ground point p along normal direction at the subpoint e of ellipsoid to the distance of the equatoriat plane and the earth's core o, ellipsoid subpoint e is to distance between described topocentric incisal plane and meridian plane intersection point t, incisal plane and meridian plane intersection point t are to the distance between ground point normal and equatoriat plane intersection point g, distance between ground point normal and equatoriat plane intersection point g and satellite s, the angle of ground point normal section and equatoriat plane intersection and satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point g.

If setting the earth's core as o, the line of ground point p and satellite s is ps, and ground point p is g along the intersection point of normal direction Yu the equatoriat plane, and the angle between line segment sp and line segment sg is ��; Angle between line segment gp and line segment gs is ��, and the latitude value of ground point p isThe longitude of ground point p is ��, and the height value of ground point p is h, and the longitude of satellite S is ��, and ground point p projection is e to the point on ellipsoid, the implicit function at some e place be F (x, y, z), calculating process is as follows:

$F(x,y,z)=\frac{x^2}{a^2}+\frac{y^2}{a^2}+\frac{z^2}{b^2}-1;$

X, y, z is asked partial derivative respectively, and the tangent equation at invocation point e place is:

$\frac{2x_e}{a^2}(x-x_e)+\frac{2y_e}{a^2}(y-y_e)+\frac{2z_e}{b^2}(z-z_e)=0,$

Draw the normal line vector in incisal plane $\stackrel{\→}{gp}=\{\frac{x_e}{a^2},\frac{y_e}{a^2},\frac{z_e}{b^2}\};$

If setting up an office, the normal section at the e place meridian plane with the intersection of the equatoriat plane and with e point excessively intersects at t point, then vectorAccording toWithInner product (or being called scalar product, the dot product) formula of two vectors, can try to achieve the angle between two vectors:

Or

In the triangle being made up of e, g and o, can draw by sine:

Again because of vector $\stackrel{\→}{og}=\{og*cos\mathrm{\λ},og*\sin \mathrm{\λ},0\}$ And vector $\stackrel{\→}{os}=\{(a+h)cos\mathrm{\ω},(a+$ $h)\sin \mathrm{\ω},0\};$

Then vector $\stackrel{\→}{gs}=\stackrel{\→}{os}-\stackrel{\→}{og}=\{(a+h)cos\mathrm{\ω}-og*cos\mathrm{\λ},(a+h)\sin \mathrm{\ω}-og*$ $\sin \mathrm{\λ},0\};$

Vector simultaneously

In right angled triangle �� egt, utilize trigonometric function relational expression can obtain line segment et and the length of line segment gt, be respectively as follows:

In triangle �� ogs, the cosine law draw:

$gs=\sqrt{{\mathrm{og}}^2+{(a+H)}^2-2*og*(a+H)cos(\mathrm{\λ}-\mathrm{\ω})}$

ByWithThe direction cosines of two vectors draw:

In triangle �� pgs, sine draw:

$\mathrm{\δ}={\sin }^{-1}\left(\frac{eg+h}{\sqrt{{(h+eg)}^2+{\mathrm{gs}}^2-2*gs*(h+eg)cos\mathrm{\θ}}}sin\mathrm{\θ}\right).$

In embodiment more preferably, in described step N3, when ground point p overlaps with equatorial line, described distance r is equal to semimajor axis of ellipsoid a.

In embodiment more preferably, in described step N3, when ground point is in a plane together with satellite, the earth's core and rotating shaft, the angle that line segment go and line segment gs is formed is 180 ��.

In embodiment more preferably, in described step N4, described appointment ground point to specified satellite stadia computation module by described step N3 obtain intermediate variable, the arbitrfary point, the ground sighting distance L to satellite is asked for the spatial triangle that equatoriat plane intersection point forms by the cosine law for by ground point, satellite and topocentric normal, and press the angle sum of a triangle principle equal to 180 degree, asking for the arbitrfary point, the ground elevation angle �� to satellite, computing formula is: $L=$

When �¡�0, described ground point is considered as absolute blind spot; As �� > 0 time, if there being barrier to block between ground point and satellite links, described ground point is then considered as relative blind spot; Described absolute blind spot refer to because of earth bending cause cannot the ground point of communication, described relative blind spot refers to that cause cannot the ground point of communication because massif blocks;

Described appointment ground point to specified satellite true north azimuth computing module described in the intermediate variable that obtains in step N3, in topocentric normal section, space right-angle triangle is collectively constituted by described normal section and the intersection point of earth axis and this normal section and the equatoriat plane and two intersection points that intersect through topocentric meridian plane, asking for the arbitrfary point, the ground true north azimuth �� to satellite by antitrigonometric function relation, computing formula is:

$\mathrm{\α}=\mathrm{\π}\±{\tan }^{-1}(\frac{gt}{et}*tan(\mathrm{\π}-{\cos }^{-1}\left(\frac{{\mathrm{og}}^2+{\mathrm{gs}}^2-{(a+H)}^2}{2*og*gs}\right)\left)\right)$

In formula described �� symbol, take as ��-�� > 0 positive sign+, take when ��-�ء�0 negative sign-.

In embodiment more preferably, in described step N5, described data conversion module is by data conversion module to be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground by calculating arbitrfary point, ground.

In specific embodiment:

In Fig. 3 numeral method for searching star schematic diagram, each parametric geometry relationship description is as follows:

Parameter shown in Fig. 3 and variable are determined and are adopted WGS84 system for: coordinate system;Semimajor axis of ellipsoid a is equal to 6378137m; Semiminor axis of ellipsoid b is equal to 6356752.3142451793m; G is acceleration of gravity; M is the quality of satellite S; M is the quality of the earth; T is earth rotation period, equal to 23h56min4s; V is the first universal speed, equal to 7.9km/s; H is the satellite S height from equator; �� is the longitude of satellite S; P is at random cake; H is the elevation of p point; �� is the longitude of p point;Latitude for p point; �� is the ground point P azimuth to satellite S; �� is the ground point P elevation angle to satellite S;

Selected xoy plane is the equatoriat plane, and x-axis points to initial longitude; Z-axis keeps consistent with the rotational ellipsoid axis of rotation; E point projects the intersection point to ellipsoid incisal plane place for p point along normal direction; G point was the normal line vector intersection point with the equatoriat plane of p point; R is the e point distance to initial point o; The intersection of the normal section and incisal plane of crossing p point is ef; Cross p point and be parallel to incisal plane and os and intersect at q point; T is incisal plane and the meridian plane intersection crossing p point. For ease of setting up unified mathematical model, being replaced in geoid spheroid incisal plane temporarily, the result of calculation impact seeking star parameter is ignored by both differences (deviation of plumb line).

For making big-dipper satellite technology be used widely in Geological Survey in China field, China Geological Survey Bureau northeastward, northwest, the area such as southwest set up some projects, having carried out some exemplary work in the field works such as regional geologic reconnaissance, mineral products prospective study, geological disaster detailed survey, region Geophysical-chemical surface sweeping, the theory simultaneously also present invention addressed and the correctness of method have carried out lot of experiments.

Wherein, have chosen several test points on the spot by high, medium and low latitude within the border in China, the result of calculation of parameters in method for searching star carries out contrast verification (table 1), result of calculation is consistent with practical situation.

Table 1, type area's big-dipper satellite method for searching star proof list

During testing, existing ground based terminal communication apparatus does not still support Beidou II (G4, G5) technology; What therefore go up the employing of table test result is a Big Dipper generation (G1, G3, G6) satellite.

The present invention relies on Ministry of Land and Resources " 12 " public welfare industry scientific research special project-" field geological work based on 3S technology manages and service key technical research and application " (No.201011010), obtains technical testing and theoretical validation widely in regional geologic reconnaissance, mineral products prospective study, investigation of hazard geology, geophysics and all entries of geochemical exploration that China northeast, northwest and section, southwest are carried out.

Wherein, the test event carried out in the Northwest mainly has: Qinghai A Er gold 1: 5 ten thousand is gathered firewood the 6 width regional geologic reconnaissance projects such as ditch (J46E005011, J46E005012, J46E005013, J46E006011, J46E006012, J46E00613); The dry width of Qinghai 1: 25 Wan Bashikuer (J46C001001), Mangnai Zhen width (J46C002001) regional geologic reconnaissance (repairing survey) project; Qinghai Province's Yushu geological disaster probe project; Qinghai Province Men Yuanxian cordierite mouth area mineral products prospective study project. The staff participating in test reaches more than 50 people, and test achieves convincing effect.

To sum up, by the test job based on stationary orbit big-dipper satellite method for searching star carried out in the wild, fully demonstrate advance and the accuracy of method for searching star provided by the invention and theory, having further showed that the present invention will play key effect in obtaining the satellite signal strength of the best rapidly and accurately and predicting the visible range (or blind area) etc. of satellite-signal in advance, technique effect obtains fully to be verified and is widely recognized as.

Above by concrete and preferred embodiment detailed describe the present invention; but those skilled in the art should be understood that; the invention is not limited in embodiment described above; all within the ultimate principle of the present invention; any amendment, combination and the equivalent replacements etc. made, are all contained within protection scope of the present invention.

Claims (10)

1. a stationary orbit geostationary satellite numeral method for searching star, it is characterised in that including:

S1: directly gather topocentric positional information by GPS or Big Dipper terminal unit; By inputting the parameter of described topocentric positional information based on the call instruction of http agreement;

S2: according to semimajor axis of ellipsoid a and semi-minor axis b and topocentric latitudeBy specify topocentric position processing module calculate ground point along normal direction at the subpoint of ellipsoid to the distance r in the earth's core;

S3: according to ellipsoidal parameter a and b and ground point latitudeThe satellite beeline to equatorial line is calculated by spheroid auxiliary variable computing module;

The angle of topocentric normal and the equatoriat plane is calculated by spheroid auxiliary variable computing module;

By spheroid auxiliary variable computing module calculating ellipsoid subpoint to the distance between described topocentric incisal plane and meridian plane intersection point;

Incisal plane and meridian plane intersection point is calculated to the distance between ground point normal and equatoriat plane intersection point by spheroid auxiliary variable computing module;

S4: by specifying ground point to calculate the distance between ground point normal and equatoriat plane intersection point and satellite to the sighting distance processing module of specified satellite; By specifying the angle of the ground point elevation angle processing module calculating ground point normal section to specified satellite and equatoriat plane intersection; By specifying ground point to calculate satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point to the true north azimuth processing module of specified satellite;

S5: by data conversion module be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground according to calculating arbitrfary point, ground in described step S3 and described step S4;

S6: seek star result described in display in human-computer interaction interface, described in seek star result and include sighting distance L, elevation angle �� and true north azimuth ��, establish the relative position of described ground point and satellite by described star result of seeking.

2. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterised in that in described step S1, the call instruction based on http agreement adopts the stipulated form of declarative state transfer interface to carry out; Described GPS or Big Dipper terminal unit include Tian Bao GPS terminal receiver, collection thinks precious hand-held set, Big Dipper terminal module, iphone4S mobile phone and Samsung S4 mobile phone.

3. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterised in that in described step S1, described topocentric positional information includes satellite longitude, ground point longitude, ground point latitude and ground point elevation.

4. stationary orbit geostationary satellite numeral method for searching star according to claim 3, it is characterized in that, described satellite longitude is appointed as the longitude of certain stationary orbit Geo-synchronous big-dipper satellite, and described longitude includes 160 ��, 140 ��, 110.5 ��, 80 �� or 58.75 ��; The described 160 �� of corresponding stationary orbit Big Dipper-G4 satellites, the described 140 �� of corresponding stationary orbit Big Dipper-G1 satellites, the described 110.5 �� of corresponding stationary orbit Big Dipper-G3 satellites, the described 80 �� of corresponding stationary orbit Big Dipper-G6 satellites, the described 58.75 �� of corresponding stationary orbit Big Dipper-G5 satellites.

5. stationary orbit geostationary satellite numeral method for searching star according to claim 3, it is characterised in that described ground point longitude, described ground point latitude and described ground point elevation are directly measured by the terminal unit with GPS function.

6. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterized in that, in described step S2, the topocentric positional information of input is converted to the topocentric positional information of Circular measure by described appointment topocentric position processing module, and the topocentric positional information calculation according to Circular measure goes out the described ground point p distance r at the subpoint e to the earth's core o of ellipsoid; Computing formula is:

Wherein, the latitude value of ground point p isSemimajor axis of ellipsoid is a, and semiminor axis of ellipsoid is b.

7. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterised in that in described step S3, first described spheroid auxiliary variable computing module calculates the satellite s minimum distance H to equatorial line, and computing formula is as follows:

By earth Near Earth Orbit Satellites speed v, orbit radius a is semimajor axis of ellipsoid, and the orbital period is T, calculates centripetal force by gravitation, and formula is:

$G\left(\frac{mM}{a^2}\right)=m\left(\frac{v^2}{a}\right);$

For stationary orbit geostationary satellite, still pressing gravitation and calculate centripetal force, formula is:

$G\left(\frac{mM}{{(a+H)}^2}\right)=m(a+H){\left(\frac{2\mathrm{\π}}{T}\right)}^2;$

In formula, G is universal gravitational constant, and m is near-earth satellite quality, and M is earth quality, then can release:

$H=\sqrt[3]{\frac{{\mathrm{av}}^2{T}^2}{4{\mathrm{\π}}^2}}-a\≈35766922m;$

Then the normal of ground point p and the angle of the equatoriat plane are calculated, ground point p along normal direction at the subpoint e of ellipsoid to the distance of the equatoriat plane and the earth's core o, ellipsoid subpoint e is to distance between described topocentric incisal plane and meridian plane intersection point t, incisal plane and meridian plane intersection point t are to the distance between ground point normal and equatoriat plane intersection point g, distance between ground point normal and equatoriat plane intersection point g and satellite s, the angle of ground point normal section and equatoriat plane intersection and satellite and ground point and the angle between described topocentric normal and equatoriat plane intersection point g,

If setting the earth's core as o, the line of ground point p and satellite s is ps, and ground point p is g along the intersection point of normal direction Yu the equatoriat plane, and the angle between line segment sp and line segment sg is ��; Angle between line segment gp and line segment gs is ��, and the latitude value of ground point p isThe longitude of ground point p is ��, and the height value of ground point p is h, and the longitude of satellite S is ��, and ground point p projection is e to the point on ellipsoid, the implicit function at some e place be F (x, y, z), calculating process is as follows:

$F(x,y,z)=\frac{x^2}{a^2}+\frac{y^2}{a^2}+\frac{z^2}{b^2}-1;$

X, y, z is asked partial derivative respectively, and the tangent equation at invocation point e place is:

$\frac{2x_e}{a^2}(x-x_e)+\frac{2y_e}{a^2}(y-y_e)+\frac{2z_e}{b^2}(z-z_e)=0,$

Draw the normal line vector in incisal plane

If setting up an office, the normal section at the e place meridian plane with the intersection of the equatoriat plane and with e point excessively intersects at t point, then vectorAccording toWithThe inner product formula of two vectors, can try to achieve the angle between two vectors:

Or

In the triangle being made up of e, g and o, can draw by sine:

Again because of vectorAnd vector

Then vector

Vector simultaneously

In right angled triangle �� egt, utilize trigonometric function relational expression can obtain line segment et and the length of line segment gt, be respectively as follows:

In triangle �� ogs, the cosine law draw:

$gs=\sqrt{{\mathrm{og}}^2+{(a+H)}^2-2*og*(a+H)cos(\mathrm{\λ}-\mathrm{\ω})};$

ByWithThe direction cosines of two vectors draw:

In triangle �� pgs, sine draw:

$\mathrm{\δ}={\sin }^{-1}\left(\frac{eg+h}{\sqrt{{(h+eg)}^2+{\mathrm{gs}}^2-2*gs*(h+eg)cos\mathrm{\θ}}}sin\mathrm{\θ}\right).$

8. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterised in that in described step S3, when ground point p overlaps with equatorial line, described distance r is equal to semimajor axis of ellipsoid a;When ground point is in a plane together with satellite, the earth's core and rotating shaft, the angle that line segment go and line segment gs is formed is 180 ��.

9. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterized in that, in described step S4, described appointment ground point to specified satellite stadia computation module by described step S3 obtain intermediate variable, the arbitrfary point, the ground sighting distance L to satellite is asked for the spatial triangle that equatoriat plane intersection point forms by the cosine law for by ground point, satellite and topocentric normal, and press the angle sum of a triangle principle equal to 180 degree, asking for the arbitrfary point, the ground elevation angle �� to satellite, computing formula is:

When �¡�0, described ground point is considered as absolute blind spot; As �� > 0 time, if there being barrier to block between ground point and satellite links, described ground point is then considered as relative blind spot; Described absolute blind spot refer to because of earth bending cause cannot the ground point of communication, described relative blind spot refers to that cause cannot the ground point of communication because massif blocks;

Described appointment ground point to specified satellite true north azimuth computing module described in the intermediate variable that obtains in step S3, in topocentric normal section, space right-angle triangle is collectively constituted by described normal section and the intersection point of earth axis and this normal section and the equatoriat plane and two intersection points that intersect through topocentric meridian plane, asking for the arbitrfary point, the ground true north azimuth �� to satellite by antitrigonometric function relation, computing formula is:

$\mathrm{\α}=\mathrm{\π}\±{\tan }^{-1}(\frac{gt}{et}*tan(\mathrm{\π}-{\cos }^{-1}\left(\frac{{\mathrm{og}}^2+{\mathrm{gs}}^2-{(a+H)}^2}{2*og*gs}\right)\left)\right);$

In formula described �� symbol, take as ��-�� > 0 positive sign+, take when ��-�ء�0 negative sign-;

Wherein, the latitude value of ground point p isThe longitude of ground point p is ��, and the height value of ground point p is h, and the longitude of satellite S is ��.

10. stationary orbit geostationary satellite numeral method for searching star according to claim 1, it is characterized in that, in described step S5, described data conversion module is by data conversion module to be converted into JSON or XML format to the elevation angle �� of satellite and arbitrfary point, ground to the result of the azimuth angle alpha of satellite to the sighting distance L of satellite, arbitrfary point, ground by calculating arbitrfary point, ground.