CN105157667A - Atmospheric polarization information-based solar altitude calculating method - Google Patents

Abstract

The invention relates to an atmospheric polarization information-based solar altitude calculating method. The method comprises designing an atmospheric polarization detection structure composed of three polarization navigation sensors to obtain polarization degree information d1, d2 and d3 of three observation points, according to relative installation positions of the three polarization navigation sensors, building a six-order polynomial constraint relationship of d1, d2, d3 and the whole airspace maximum polarization degree dmax, determining the whole airspace maximum polarization degree dmax by the polarization degree six-order polynomial constraint relationship, and according to the dmax, determining solar altitude gamma in a polarization navigation sensor module coordinate system. The method has the advantages of simple structure and high precision, utilizes atmospheric polarization information to calculate solar altitude and is used for carrier three dimensional navigation positioning.

Description

A kind of sun altitude computing method based on atmosphere polarization information

Technical field

The present invention relates to a kind of sun altitude computing method based on atmosphere polarization information, can be used for the modeling of aircraft polarization combination navigational system, polarization degree information is applied in measurement equation, simplify polarization and lead combination boat system model, improve the observability of system model, and then improve polarization combination navigational system alignment precision and navigation accuracy.

Background technology

Atmospheric polarization phenomenon is a kind of natural quality of light, and polarized light is extensively present in physical environment, and atmospheric polarization distribution pattern is relatively stable, wherein contains abundant navigation information.Scientist finds that a lot of biology of occurring in nature can both utilize polarized light to navigate, ground husky ant, the honeybee flown in the air, water-bed lobster etc. are all utilize polarized light to carry out the representative of navigating, and corresponding achievement is published on the magazines such as Nature, Science.

Navigate mode based on polarization information has the features such as autonomous, passive, radiationless, good concealment, enter 21 century, the countries such as America and Europe are in order to improve without combined navigation system performance in satellite navigation situation, more focus on research and implement novel independent navigation mode, polarization navigational system technology obtains and develops rapidly.

At present, the difficult point of polarization navigational system technology is extraction and the application of polarization navigation information, the biological utilisation such as ant, honeybee polarized light realizes two dimensional navigation, mainly utilize the directivity characteristics that atmospheric polarization distributes, judged from health axle and the meridianal angle of the sun by the polarization direction of perception sky polarized light.In order to mimic biology utilizes atmospheric polarization characteristic to carry out the ability of navigating, Chinese scholars have developed bionical polarization navigation sensor according to biology compound eye structure, by measuring the light intensity in aerial a certain some different polarization direction, sky, calculate the polarization state information of observation station---polarization direction and degree of polarization.

Real atmosphere is due to cloud layer, gasoloid, the existence of the large particulate matters such as water droplet and ground return phenomenon, atmospheric polarization type is caused to present various undesirable state, this nonideality makes full spatial domain degree of polarization maximal value be not equal to 1, and this nonideality is not obvious for the impact of polarization direction, therefore in existing polarization airmanship, mainly utilize polarization direction to determine carrier course, have ignored the use to atmosphere polarization information another one important information-degree of polarization, this phenomenon causes utilizing atmosphere polarization information insufficient, limit the application of polarization airmanship on three-dimensional navigation.Atmospheric polarization phenomenon, as an important sign of sunshine, contain the azimuth information of the sun, and solar azimuth Information Availability is located in the three-dimensional navigation of carrier, there is no the report utilizing atmosphere polarization information determination sun altitude at present.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome existing polarization information and utilize this defect insufficient, utilize atmosphere polarization information to ask for sun altitude, locate for carrier three-dimensional navigation.The present invention proposes a kind of three polarization navigation sensor combine detection structures, the detection side of appropriate design three polarization navigation sensors to, set up observation station degree of polarization and the maximum degree of polarization d in full spatial domain _maxbetween six rank Involving Certain Polynomial Constraints relations, realize the maximum degree of polarization d in full spatial domain _maxresolve, and then realize solving of sun altitude γ under module coordinate system, provide the effective way that polarization degree information is used carrier navigation by.The method structure is simple, algorithm is easy to realize, the complexity that sun altitude γ under polarization module coordinate system can simplify polarization combination navigation model is greatly introduced in polarization combination navigation model, improve the observability of integrated navigation system, and then improve integrated navigation system alignment precision and navigation accuracy.

Technical solution of the present invention is: a kind of sun altitude computing method based on atmosphere polarization information, and implementation step is as follows:

(1) first the maximum degree of polarization d in whole day territory is designed _maxdetection architecture, this detection architecture is made up of three polarization navigation sensors, the real-time degree of polarization to aerial three observation stations in sky and polarization direction information carry out feature extraction, wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor is arranged on module coordinate system z-axis direction, two auxiliary polarization navigation sensors are arranged on main polarization navigation sensor both sides, and the angle between two auxiliary polarization navigation sensor main shafts and main polarization navigation sensor main shaft is η;

(2) according to the maximum degree of polarization d in whole day territory that (1) is designed _maxdetection architecture, obtains the degree of polarization measured value of aerial three observation stations in sky, sets up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, determine the maximum degree of polarization d in full spatial domain _max;

(3) according to the maximum degree of polarization d in full spatial domain that (2) obtain _maxvalue, based on the sun altitude γ of atmosphere polarization information under determination module coordinate system.

Described step (1) first designs the maximum degree of polarization d in whole day territory _maxdetection architecture, this detection architecture is made up of three polarization navigation sensors, the real-time degree of polarization to aerial three observation stations in sky and polarization direction information carry out feature extraction, wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor is arranged on module coordinate system z-axis direction, two auxiliary polarization navigation sensors are arranged on main polarization navigation sensor both sides, angle between two auxiliary polarization navigation sensor main shafts and main polarization navigation sensor main shaft is η, is implemented as follows:

The design maximum degree of polarization d in whole day territory _maxdetection architecture, this detection architecture is made up of three polarization navigation sensors, and wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor A ₁mounting plane and the coordinate that forms of observed ray be module coordinate system Mxyz, M be true origin, xy axle place plane is main polarization navigation sensor A ₁mounting plane, z-axis positive dirction is main polarization navigation sensor A ₁observed ray, other two auxiliary polarization navigation sensor A ₂, A ₃symmetry is arranged on main polarization navigation sensor A ₁both sides, two auxiliary polarization navigation sensor main shafts and the angle of main polarization navigation sensor main shaft in mounting plane are η, η ∈ (0,90 °);

With true origin M for centre of sphere tectonic unit celestial sphere, the projection of observation station on unit celestial sphere of three polarization navigation sensors is respectively Q ₁, Q ₂, Q ₃, MQ ₁, MQ ₂, MQ ₃represent three polarization navigation sensor A respectively ₁, A ₂, A ₃the unit vector of observed ray, according to the maximum degree of polarization d in whole day territory _maxdetection architecture is known, and the observed ray of three polarization navigation sensors is coplanar, then MQ ₁, MQ ₂, MQ ₃with z-axis in same plane, and MQ ₂, MQ ₃lay respectively at MQ ₁both sides, with MQ ₁angle be η, η ∈ (0,90 °);

By the maximum degree of polarization d in whole day territory of design _maxdetection architecture, Real-time Obtaining A ₁, A ₂, A ₃the degree of polarization measured value of three polarization navigation sensors, uses d respectively ₁, d ₂, d ₃represent;

The maximum degree of polarization d in whole day territory that described step (2) designs according to (1) _maxdetection architecture, obtains the degree of polarization measured value of aerial three observation stations in sky, sets up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, determine the maximum degree of polarization d in full spatial domain _max, be implemented as follows:

Following relation is had based on the theoretical observation station degree of polarization of Rayleigh scattering and polarization view angle:

$\frac{d_n}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_n}{1+{\cos }^2{\mathrm{\θ}}_n}$

Wherein, d _nby the n-th polarization navigation sensor is surveyed observation station degree of polarization, be the maximal value of three observation station degree of polarizations, θ _nthe angle of the n-th polarization navigation sensor observed ray and solar vector MS, S is the projection of the sun on unit celestial sphere, and MS is the solar direction unit vector under module coordinate system, θ _n∈ [0, π], n ∈ { 1,2,3};

Three polarization navigation sensor A ₁, A ₂, A ₃observed ray MQ ₁, MQ ₂, MQ ₃θ is respectively with the angle of solar vector MS ₁, θ ₂, θ ₃, theoretical according to Rayleigh scattering, then have:

$\left\{\begin{array}{c}\frac{d_1}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_1}{1+{\cos }^2{\mathrm{\θ}}_1}\\ \frac{d_2}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_2}{1+{\cos }^2{\mathrm{\θ}}_2}\\ \frac{d_3}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_3}{1+{\cos }^2{\mathrm{\θ}}_3}\end{array}\right.$

Wherein, θ ₁be main polarization navigation sensor A ₁observed ray MQ ₁with the angle of MS, θ ₂be second polarization navigation sensor A ₂observed ray MQ ₂with the angle of MS, θ ₃be the 3rd polarization navigation sensor A ₃observed ray MQ ₃with the angle of MS;

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, main polarization navigation sensor A ₁observed ray MQ ₁overlap with module coordinate system z-axis, therefore have following equation to set up:

θ ₁+γ＝π/2

Wherein, be sun altitude under module coordinate system with γ;

At spherical triangle △ Q ₂q ₁s and △ Q ₃q ₁the spherical triangle cosine law is utilized to obtain in S:

cosθ ₂＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₂

cosθ ₃＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₃

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, MQ ₁, MQ ₂, MQ ₃in same plane, then ∠ SQ ₁q ₂+ ∠ SQ ₁q ₃=π, θ ₁, θ ₂, θ ₃between relation can be expressed as:

cosθ ₂+cosθ ₃＝2cosηcosθ ₁

Make a=2cos η, the maximum degree of polarization d in whole day territory _maxrelative installation in detection architecture between three polarization navigation sensors, and three observation station degree of polarizations and polarization view angle relation, set up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, at real number interval interior equation existence and unique solution;

α ₆d _max ⁶+α ₅d _max ⁵+α ₄d _max ⁴+α ₃d _max ³+α ₂d _max ²+α ₁d _max+α ₀＝0

Wherein:

α ₆＝4a ²-a ⁴

α ₅＝2a ⁴d ₁+(4a ²-2a ⁴)d ₂+(4a ²-2a ⁴)d ₃

α ₄＝4a ⁴d ₁d ₂+4a ⁴d ₁d ₃+(8-4a ⁴)d ₂d ₃-(a ⁴+4a ²)d ₁ ²-(a ⁴+4)d ₂ ²-(a ⁴+4)d ₃ ²

α ₃＝(8a ⁴+16)d ₁d ₂d ₃-(8-2a ⁴)d ₁d ₂ ²-(2a ⁴+4a ²)d ₁ ²d ₂-(8-2a ⁴)d ₁d ₃ ²。

-(2a ⁴+4a ²)d ₁ ²d ₃-(2a ⁴+4a ²)d ₂d ₃ ²-(2a ⁴+4a ²)d ₂ ²d ₃

α ₂＝(8-4a ⁴)d ₁ ²d ₂d ₃+4a ⁴d ₁d ₂ ²d ₃+4a ⁴d ₁d ₂d ₃ ²

-(4+a ⁴)d ₁ ²d ₂ ²-(4+a ⁴)d ₁ ²d ₃ ²-(a ⁴+4a ²)d ₂ ²d ₃ ²

α ₁＝2a ⁴d ₁ ²d ₂ ²d ₃+(4a ²-2a ⁴)d ₁ ²d ₂d ₃ ³+(4a ²-2a ⁴)d ₁d ₂ ²d ₃ ²

α ₀＝(4a ²-a ⁴)d ₁ ²d ₂ ²d ₃ ²

The maximum degree of polarization d in full spatial domain that basis (2) in described step (3) obtains _maxvalue, based on the sun altitude γ of atmosphere polarization information under determination module coordinate system, be implemented as follows:

According to the maximum degree of polarization d in full spatial domain that step (2) obtains _max, obtain main polarization navigation sensor A ₁polarization view angle θ ₁for:

${\cos }^2{\mathrm{\θ}}_1=\frac{d_{\max }-d_1}{d_{\max }+d_1}$

${\mathrm{\θ}}_1=\mathrm{arc}\cos (\±\sqrt{\frac{d_{\max }-d_1}{d_{\max }+d_1}})$

Wherein, ± represent θ ₁pi/2 may be less than and also may be greater than pi/2 ,+or-selection can be judged by extraneous additional intensity sensor.

According to the main polarization navigation sensor A of step (1) ₁mounting means and step (2) sun altitude γ and scatteringangleθ ₁between relation, under obtaining module coordinate system, sun altitude γ is:

γ＝π/2-θ ₁

Principle of the present invention is: have certain symmetry based on the theoretical atmospheric polarization distribution pattern of Rayleigh scattering, the distribute distribution character at a time a certain geographic position of full spatial domain polarization direction and degree of polarization is fixing, the polarization information that polarization navigation sensor can realize the aerial a certain point in sky is measured, but because atmospheric polarization degree distribution character is nonideality, certain some polarization degree information cannot fully in polarization navigational system.The present invention is directed to polarization information cannot make full use of with polarization navigational system, proposes one and utilizes atmosphere polarization information to ask for sun altitude method, is utilized by polarization information and reaches maximization.First, a kind of three sensor Polarization Detection structures are constructed, the installation direction of appropriate design three polarization navigation sensors; Then, the theoretical and spherical triangle cosine law based on Rayleigh scattering, constructs contacting between the maximum degree of polarization of three observation station polarization degree information and full spatial domain; Finally, sun altitude γ under polarization module coordinate system is obtained by solving nonlinear multivariable system of equations.

The present invention's advantage is compared with prior art:

(1) the present invention devises the three maximum degree of polarization d in the full spatial domain of sensor _maxdetection architecture, by reasonably designing the installation direction of three polarization navigation sensors, sets up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, reduce solve the maximum degree of polarization d in full spatial domain _maxdifficulty, ask d with traditional by full spatial domain polarization imaging method _maxstructure compared, cost, algorithm complex reduce, and add system redundancy simultaneously.According to the maximum degree of polarization d in full spatial domain _maxvalue, ask for sun altitude, the three-dimensional navigation for carrier is located.

Accompanying drawing explanation

Fig. 1 is design flow diagram of the present invention;

Fig. 2 is for the present invention relates to three polarization navigation sensor detection architecture schematic diagram;

Fig. 3 is sun altitude γ and polarization view angle θ schematic diagram under the polarization module coordinate system that the present invention relates to.

Embodiment

As shown in Figure 1, specific implementation step of the present invention is as follows:

1, the maximum degree of polarization d in whole day territory is designed _maxdetection architecture, in real time feature extraction is carried out to the degree of polarization of aerial three observation stations in sky and polarization direction information:

First the maximum degree of polarization d in whole day territory is designed _maxdetection architecture, as shown in Figure 2, this detection architecture is made up of three polarization navigation sensors, and wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor A ₁mounting plane and the coordinate that forms of observed ray be module coordinate system Mxyz, M be true origin, xy axle place plane is main polarization navigation sensor A ₁mounting plane, z-axis positive dirction is main polarization navigation sensor A ₁observed ray, other two auxiliary polarization navigation sensor A ₂, A ₃symmetry is arranged on main polarization navigation sensor A ₁both sides, two auxiliary polarization navigation sensor main shafts and the angle of main polarization navigation sensor main shaft in mounting plane are η, η ∈ (0,90 °);

With true origin M for centre of sphere tectonic unit celestial sphere, the projection of observation station on unit celestial sphere of three polarization navigation sensors is respectively Q ₁, Q ₂, Q ₃, MQ ₁, MQ ₂, MQ ₃represent three polarization navigation sensor A respectively ₁, A ₂, A ₃the unit vector of observed ray, according to the maximum degree of polarization d in whole day territory _maxdetection architecture is known, and three polarization navigation sensors are coplanar, then MQ ₁, MQ ₂, MQ ₃with z-axis in same plane, and MQ ₂, MQ ₃lay respectively at MQ ₁both sides, with MQ ₁angle be η, η ∈ (0,90 °);

By the maximum degree of polarization d in whole day territory of design _maxdetection architecture, Real-time Obtaining A ₁, A ₂, A ₃the degree of polarization measured value of three polarization navigation sensors, uses d respectively ₁, d ₂, d ₃represent;

2, degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations is set up _maxbetween six rank Involving Certain Polynomial Constraints relations:

Following relation is had based on the theoretical observation station degree of polarization of Rayleigh scattering and polarization view angle (scattering angle):

$\frac{d_n}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_n}{1+{\cos }^2{\mathrm{\θ}}_n}$

Wherein, d _nby the n-th polarization navigation sensor is surveyed observation station degree of polarization, be the maximal value of three observation station degree of polarizations, θ _nthe angle of the n-th polarization navigation sensor observed ray and solar vector MS, S is the projection of the sun on unit celestial sphere, and MS is the solar direction unit vector under module coordinate system, θ _n∈ [0, π], n ∈ { 1,2,3};

Three polarization navigation sensor A ₁, A ₂, A ₃observed ray MQ ₁, MQ ₂, MQ ₃θ is respectively with the angle of solar vector MS ₁, θ ₂, θ ₃, theoretical according to Rayleigh scattering, then have:

$\left\{\begin{array}{c}\frac{d_1}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_1}{1+{\cos }^2{\mathrm{\θ}}_1}\\ \frac{d_2}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_2}{1+{\cos }^2{\mathrm{\θ}}_2}\\ \frac{d_3}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_3}{1+{\cos }^2{\mathrm{\θ}}_3}\end{array}\right.$

Wherein, θ ₁be main polarization navigation sensor A ₁observed ray MQ ₁with the angle of MS, θ ₂be second polarization navigation sensor A ₂observed ray MQ ₂with the angle of MS, θ ₃be the 3rd polarization navigation sensor A ₃observed ray MQ ₃with the angle of MS;

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, main polarization navigation sensor A ₁observed ray MQ ₁overlap with module coordinate system z-axis, therefore have following equation to set up:

θ ₁+γ＝π/2

Wherein, be sun altitude under module coordinate system with γ;

At spherical triangle △ Q ₂q ₁s and △ Q ₃q ₁the spherical triangle cosine law is utilized to obtain in S:

cosθ ₂＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₂

cosθ ₃＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₃

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, MQ ₁, MQ ₂, MQ ₃in same plane, then ∠ SQ ₁q ₂+ ∠ SQ ₁q ₃=π, θ ₁, θ ₂, θ ₃between relation can be expressed as:

cosθ ₂+cosθ ₃＝2cosηcosθ ₁

Make a=2cos η, the maximum degree of polarization d in whole day territory _maxrelative installation in detection architecture between three polarization navigation sensors, and three observation station degree of polarizations and polarization view angle relation, set up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, at real number interval interior equation existence and unique solution;

α ₆d _max ⁶+α ₅d _max ⁵+α ₄d _max ⁴+α ₃d _max ³+α ₂d _max ²+α ₁d _max+α ₀＝0

Wherein:

α ₆＝4a ²-a ⁴

α ₅＝2a ⁴d ₁+(4a ²-2a ⁴)d ₂+(4a ²-2a ⁴)d ₃

α ₄＝4a ⁴d ₁d ₂+4a ⁴d ₁d ₃+(8-4a ⁴)d ₂d ₃-(a ⁴+4a ²)d ₁ ²-(a ⁴+4)d ₂ ²-(a ⁴+4)d ₃ ²

α ₃＝(8a ⁴+16)d ₁d ₂d ₃-(8-2a ⁴)d ₁d ₂ ²-(2a ⁴+4a ²)d ₁ ²d ₂-(8-2a ⁴)d ₁d ₃ ²

-(2a ⁴+4a ²)d ₁ ²d ₃-(2a ⁴+4a ²)d ₂d ₃ ²-(2a ⁴+4a ²)d ₂ ²d ₃

α ₂＝(8-4a ⁴)d ₁ ²d ₂d ₃+4a ⁴d ₁d ₂ ²d ₃+4a ⁴d ₁d ₂d ₃ ²

-(4+a ⁴)d ₁ ²d ₂ ²-(4+a ⁴)d ₁ ²d ₃ ²-(a ⁴+4a ²)d ₂ ²d ₃ ²

α ₁＝2a ⁴d ₁ ²d ₂ ²d ₃+(4a ²-2a ⁴)d ₁ ²d ₂d ₃ ³+(4a ²-2a ⁴)d ₁d ₂ ²d ₃ ²

α ₀＝(4a ²-a ⁴)d ₁ ²d ₂ ²d ₃ ²

3, under determination module coordinate system based on the sun altitude γ of atmosphere polarization information.

According to the maximum degree of polarization d in full spatial domain that step (2) obtains _max, based on the sun altitude γ of atmosphere polarization information under determination module coordinate system, as shown in Figure 3, be implemented as follows:

According to the maximum degree of polarization d in full spatial domain that step (2) obtains _max, obtain main polarization navigation sensor A ₁polarization view angle θ ₁for:

${\cos }^2{\mathrm{\θ}}_1=\frac{d_{\max }-d_1}{d_{\max }+d_1}$

${\mathrm{\θ}}_1=\mathrm{arc}\cos (\±\sqrt{\frac{d_{\max }-d_1}{d_{\max }+d_1}})$

Wherein, ± represent θ ₁pi/2 may be less than and also may be greater than pi/2 ,+or-selection can be judged by extraneous additional intensity sensor.

According to the main polarization navigation sensor A of step (1) ₁mounting means and step (2) sun altitude γ and scatteringangleθ ₁between relation, under obtaining module coordinate system, sun altitude γ is:

γ＝π/2-θ ₁。

Claims (4)

1., based on sun altitude computing method for atmosphere polarization information, it is characterized in that:

(1) first the maximum degree of polarization d in whole day territory is designed _maxdetection architecture, this detection architecture is made up of three polarization navigation sensors, the real-time degree of polarization to aerial three observation stations in sky and polarization direction information carry out feature extraction, wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor is arranged on module coordinate system z-axis direction, two auxiliary polarization navigation sensors are arranged on main polarization navigation sensor both sides, and the angle between two auxiliary polarization navigation sensor main shafts and main polarization navigation sensor main shaft is η;

(2) according to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, obtains the degree of polarization measured value of aerial three observation stations in sky, sets up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, determine the maximum degree of polarization d in full spatial domain _max;

(3) according to the maximum degree of polarization d in full spatial domain that step (2) obtains _maxvalue, based on the sun altitude γ of atmosphere polarization information under determination module coordinate system.

2. a kind of sun altitude computing method based on atmosphere polarization information according to claim 1, is characterized in that: being implemented as follows of described step (1) detection architecture:

The design maximum degree of polarization d in whole day territory _maxdetection architecture, this detection architecture is made up of three polarization navigation sensors, and wherein three polarization navigation sensors are arranged in same plane, main polarization navigation sensor A ₁mounting plane and the coordinate that forms of observed ray be module coordinate system Mxyz, M be true origin, xy axle place plane is main polarization navigation sensor A ₁mounting plane, z-axis positive dirction is main polarization navigation sensor A ₁observed ray, other two auxiliary polarization navigation sensor A ₂, A ₃symmetry is arranged on main polarization navigation sensor A ₁both sides, two auxiliary polarization navigation sensor main shafts and the angle of main polarization navigation sensor main shaft in mounting plane are η, η ∈ (0,90 °);

With true origin M for centre of sphere tectonic unit celestial sphere, the projection of observation station on unit celestial sphere of three polarization navigation sensors is respectively Q ₁, Q ₂, Q ₃, MQ ₁, MQ ₂, MQ ₃represent three polarization navigation sensor A respectively ₁, A ₂, A ₃the unit vector of observed ray, according to the maximum degree of polarization d in whole day territory _maxdetection architecture is known, and the observed ray of three polarization navigation sensors is coplanar, then MQ ₁, MQ ₂, MQ ₃with z-axis in same plane, and MQ ₂, MQ ₃lay respectively at MQ ₁both sides, with MQ ₁angle be η, η ∈ (0,90 °);

By the maximum degree of polarization d in whole day territory of design _maxdetection architecture, Real-time Obtaining A ₁, A ₂, A ₃the degree of polarization measured value of three polarization navigation sensors, uses d respectively ₁, d ₂, d ₃represent.

3. a kind of sun altitude computing method based on atmosphere polarization information according to claim 1, is characterized in that: the complete maximum degree of polarization d in spatial domain of described step (2) _maxbe implemented as follows:

Following relation is had based on the theoretical observation station degree of polarization of Rayleigh scattering and polarization view angle:

$\frac{d_n}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_n}{1+{\cos }^2{\mathrm{\θ}}_n}$

Wherein, d _nby the n-th polarization navigation sensor is surveyed observation station degree of polarization, be the maximal value of three observation station degree of polarizations, θ _nthe angle of the n-th polarization navigation sensor observed ray and solar vector MS, S is the projection of the sun on unit celestial sphere, and MS is the solar direction unit vector under module coordinate system, θ _n∈ [0, π], n ∈ { 1,2,3};

Three polarization navigation sensor A ₁, A ₂, A ₃observed ray MQ ₁, MQ ₂, MQ ₃θ is respectively with the angle of solar vector MS ₁, θ ₂, θ ₃, theoretical according to Rayleigh scattering, then have:

$\left\{\begin{array}{c}\frac{d_1}{d_{\max }}=\frac{{\sin }^2\mathrm{\θ}}{1+{\cos }^2{\mathrm{\θ}}_1}\\ \frac{d_2}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_2}{1+{\cos }^2{\mathrm{\θ}}_2}\\ \frac{d_3}{d_{\max }}=\frac{{\sin }^2{\mathrm{\θ}}_3}{1+{\cos }^2{\mathrm{\θ}}_3}\end{array}\right.$

Wherein, θ ₁be main polarization navigation sensor A ₁observed ray MQ ₁with the angle of MS, θ ₂be second polarization navigation sensor A ₂observed ray MQ ₂with the angle of MS, θ ₃be the 3rd polarization navigation sensor A ₃observed ray MQ ₃with the angle of MS;

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, main polarization navigation sensor A ₁observed ray MQ ₁overlap with module coordinate system z-axis, therefore have following equation to set up: θ ₁+ γ=pi/2

Wherein, γ is sun altitude under module coordinate system;

At spherical triangle Δ Q ₂q ₁s and Δ Q ₃q ₁the spherical triangle cosine law is utilized to obtain in S:

cosθ ₂＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₂

cosθ ₃＝cosθ ₁cosη+sinθ ₁sinηcos∠SQ ₁Q ₃

According to the maximum degree of polarization d in whole day territory that step (1) designs _maxdetection architecture, MQ ₁, MQ ₂, MQ ₃in same plane, then ∠ SQ ₁q ₂+ ∠ SQ ₁q ₃=π, θ ₁, θ ₂, θ ₃between relation can be expressed as:

cosθ ₂+cosθ ₃＝2cosηcosθ ₁

Make a=2cos η, the maximum degree of polarization d in whole day territory _maxrelative installation in detection architecture between three polarization navigation sensors, and three observation station degree of polarizations and polarization view angle relation, set up degree of polarization and the maximum degree of polarization d in full spatial domain of three observation stations _maxbetween six rank Involving Certain Polynomial Constraints relations, at real number interval interior equation existence and unique solution;

α ₆d _max ⁶+α ₅d _max ⁵+α ₄d _max ⁴+α ₃d _max ³+α ₂d _max ²+α ₁d _max+α ₀＝0

Wherein:

$\begin{array}{c}{\mathrm{\α}}_6={4a\mathrm{}}^2-a^4\\ {\mathrm{\α}}_5={2a}^4{d}_1+({4a}^2-{2a}^4)d_2+({4a}^2-{2a}^4)d_3\\ {\mathrm{\α}}_4={4a}^4{d}_1{d}_2+{4a}^4{d}_1{d}_3+(8-{4a}^4)d_2{d}_3-(a^4+{4a}^2){d_1}^2-(a^4+4){d_2}^2-(a^4+4){d_3}^2\\ {\mathrm{\α}}_3=({8a}^4+16)d_1{d}_2{d}_3-(8-{2a}^4)d_1{d_2}^2-({2a}^4+{4a}^2){d_1}^2{d}_2-(8-{2a}^4)d_1{d_3}^2\\ -({2a}^4+{4a}^2){d_1}^2{d}_3-({2a}^4+{4a}^2)d_2{d_3}^2-({2a}^4+{4a}^2){d_2}^2{d}_3\\ a_2=(8-{4a}^4){d_1}^2{d}_2{d}_3+{4a}^4{d}_1{d_2}^2{d}_3+{4a}^4{d}_1{d}_2{d_3}^2\\ -(4+a^4){d_1}^2{d_2}^2-(4+a^4){d_1}^2{d_3}^2-(a^4+{4a}^2){d_2}^2{d_3}^2\\ {\mathrm{\α}}_1={2a}^4{d_1}^2{d_2}^2{d}_3+({4a}^2-{2a}^4){d_1}^2{d}_2{d_3}^3+({4a}^2-{2a}^4)d_1{d_2}^2{d_3}^2\\ {\mathrm{\α}}_0=({4a}^2-a^4){d_1}^2{d_2}^2{d_3}^2\end{array}.$

4. a kind of sun altitude computing method based on atmosphere polarization information according to claim 1, is characterized in that: the middle sun altitude γ of described step (3) is implemented as follows:

According to the maximum degree of polarization d in full spatial domain that step (2) obtains _max, obtain main polarization navigation sensor A ₁polarization view angle θ ₁for:

${\cos }^2{\mathrm{\θ}}_1=\frac{d_{\max }-d_1}{d_{\max }+d_1}$

${\mathrm{\θ}}_1=\arccos (\±\sqrt{\frac{d_{\max }-d_1}{d_{\max }+d_1}})$

Wherein, ± represent θ ₁pi/2 may be less than and also may be greater than pi/2 ,+or-selection can be judged by extraneous additional intensity sensor;

According to the main polarization navigation sensor A of step (1) ₁mounting means and step (2) sun altitude γ and scatteringangleθ ₁between relation, under obtaining module coordinate system, sun altitude γ is:

γ＝π/2-θ ₁。