CN103528682A - Method for simulating entrance pupil radiance data of continental rise imaging spectrometer on flat lunar surface - Google Patents

Abstract

A method for simulating entrance pupil radiance data of a continental rise imaging spectrometer on a flat lunar surface is a support technology in the field of deep space exploration. A simulated entrance pupil radiance data cube of the continental rise imaging spectrometer is finally obtained through setting simulation parameters, establishing a coordinate system for a continental rise platform, determining the coordinate of the center of a picture element, respectively calculating the solar direct irradiance received in a field of view, the specular reflection irradiance of the continental rise platform received in the field of view and the diffuse reflection irradiance of the continental rise platform received in the field of view, and supposing that the lunar surface is a Lambert reflector. By using the method provided by the invention, the optimal observation geometry is designed for certain illumination geometry, the influence of the continental rise platform is removed in the process of preprocessing of the data, so that the quality of the imaging data and the application prospect of the continental rise imaging spectrometer under a lunar surface environment are improved.

Description

The analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology

(1) technical field

The analogy method that the present invention relates to continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology, is used in before the imaging of continental rise imaging spectrometer, for a certain illumination how much, how much of the observations of devise optimum; After imaging, in process of data preprocessing, rejecting the impact of continental rise platform in imaging data cube, is a support technology in survey of deep space field.

(2) background technology

The moon contains abundant mineral resources, the reserves of some mineral resources are even far away higher than the reserves of the earth, this demand resource being increased day by day to human society provides a solution, to the moon can assess in-orbit distribution and the reserves of moon mineral resources with continental rise remote sensing, become a focus of international survey of deep space.

Under menology environment in continental rise imaging spectrometer imaging process, shade and reflected radiation meeting that continental rise platform produces impact imaging data, under how much of a certain illumination, for how much continental rise platforms of different observation, the influence degree of imaging data is had to difference, need to select an optimum observation how much, to obtain high-quality imaging data.Obtaining and transmitting all of deep space data is not easy, and for the data that continental rise imaging spectrometer is obtained, can make the best use of everything, and need to carry out pre-service to data, rejects the impact of continental rise platform as far as possible.And at menology environment, the impact of quantitative measurment continental rise platform on the spot, utilize the method for Computer Simulation to generate required illumination and observe simulation entrance pupil spoke brightness data and platform under how much affect data, the influence degree of assessment continental rise platform, provides a kind of solution route for rejecting the impact of continental rise platform in the optimum observed pattern of design continental rise imaging spectrometer and process of data preprocessing.

For the simulation modeling of imaging spectrometer entrance pupil spoke brightness, be at present all that the airborne or Space-borne remote sensor of simulation is to earth observation, by setting up discrete ground scene simulated atmosphere road radiation transmission process, obtain the discrete spectrum spoke Luminance Distribution of imaging spectrometer At The Height, be not suitable for the imaging simulation of continental rise imaging spectrometer under menology environment.

(3) summary of the invention

The object of the invention is to propose the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology, simulation process is considered shade and the impact of reflected radiation on imaging data of continental rise platform, make its actual physical process that meets the imaging of menology continental rise imaging spectrometer, improved the authenticity of simulated data.

Technical solution of the present invention is: according to how much of the three-dimensional positions of continental rise platform three-dimensional dimension, imaging spectrometer, illumination with observe how much, by radiation transportation simulator, calculate beam radia, the mirror-reflection radiation of continental rise platform and continental rise platform diffuse reflection radiation that visual field receives, suppose that menology is lambert's body, finally calculate the entrance pupil spoke brightness data cube of continental rise imaging spectrometer.

The analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology of the present invention, its step is as follows:

(1) set illumination geometric parameter, observation geometric parameter, continental rise platform parameter, continental rise imaging spectral instrument parameter and menology reflectivity data cube, wherein, illumination geometric parameter comprises: sun altitude and solar azimuth; Observation geometric parameter comprises: observation zenith angle and observed azimuth; Continental rise platform parameter comprises: the Reflectivity Model of the three-dimensional profile structure of continental rise platform, each surperficial size and continental rise platform surface; Continental rise imaging spectral instrument parameter comprises: the space dimension ranks pixel numbers (m, n) of the three-dimensional position relation of the three-dimensional profile structure of continental rise imaging spectrometer and size, continental rise imaging spectrometer and continental rise platform, field angle and each imaging; The cubical space of menology reflectivity data dimension ranks number is m * n;

(2) set up continental rise platform coordinate system, and illumination geometric parameter in step (1) is transformed to continental rise platform coordinate system, calculate all in continental rise platform coordinate system later;

(3), according to the continental rise imaging spectral instrument parameter of setting in step (1), observation geometric parameter, calculate the centre coordinate of continental rise imaging spectrometer each pixel in menology visual field;

(4), according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the beam radia that in visual field, each pixel receives;

(5) according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the continental rise platform mirror-reflection radiation that in visual field, each pixel receives;

(6) according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the continental rise platform diffuse reflection radiation that in visual field, each pixel receives;

(7) generate the simulation entrance pupil spoke brightness cube of continental rise imaging spectrometer.

Wherein, the continental rise platform coordinate system described in step (2) refers to that take continental rise platform bottom center is initial point in the vertical projection of menology, rotates sky, the northeast coordinate system at initial point place around celestial axis

angle, obtains continental rise platform coordinate system, and the east of sky, northeast coordinate system, north, celestial axis is corresponding to the x, y, z axle of continental rise platform coordinate system, and wherein, against turning axle, see and be rotated counterclockwise as just,

for observed azimuth.

Wherein, " calculating the irradiance of the beam radia that in visual field, each pixel receives " described in step (4), its concrete operations are: according to the centre coordinate of illumination geometric parameter, observation geometric parameter, continental rise platform parameter and visual field pixel, calculate the scope being covered by continental rise platform shade in menology visual field, generate visual field shadow matrix S, in visual field, ranks number are the irradiance E of the beam radia that receives of the pixel of (i, j) ₀be expressed as:

E ₀(i，j)＝E _sunS(i，j)cosθ

Wherein, E _sunbe that the menology sun vertically irradiates irradiance, can use the outer solar irradiance value of earth atmosphere; θ is solar zenith angle; S is visual field shadow matrix, if ranks number are that the pixel of (i, j) is covered by continental rise platform shade in visual field, and S (i, j)=0, otherwise S (i, j)=1.

Wherein, " calculating the irradiance of the continental rise platform mirror-reflection radiation that in visual field, each pixel receives " described in step (5), its concrete operations are: according to the centre coordinate of illumination geometric parameter, observation geometric parameter, continental rise platform parameter and visual field pixel, calculate the scope being illuminated by continental rise platform k surperficial mirror-reflection in menology visual field, generate visual field mirror reflecting matrix M _k, in visual field, ranks number are the irradiance E of the platform mirror-reflection radiation that receives of the pixel of (i, j) ₁be expressed as:

$E_1(i,j)=\underset{k}{\mathrm{\Σ}}{E}_{\mathrm{sun}}{\mathrm{\ρ}}_M{M}_k(i,j)\cos {\mathrm{\θ}}_{1k}$

Wherein, θ _1kit is the supplementary angle of continental rise platform k surperficial minute surface reflection ray and menology normal angle; ρ _mit is continental rise platform specular reflectance; M _kthe visual field mirror reflecting matrix on k, corresponding continental rise platform surface, if ranks number be that the pixel of (i, j) is illuminated by k surperficial mirror-reflection of continental rise platform in visual field, M _k(i, j)=1, otherwise M _k(i, j)=0.

Wherein, " calculating the irradiance of the continental rise platform diffuse reflection radiation that in visual field, each pixel receives " described in step (6), its concrete operations are: the irradiance E of the continental rise platform diffuse reflection radiation that the pixel that in visual field, ranks number are (i, j) receives ₂be expressed as:

$E_2(i,j)=\underset{k}{\mathrm{\&Sigma;}}[{\mathrm{<figure-callout\; id="3k"\; label="E"\; filenames="HDA0000403721720000021.png"\; state="\{\{state\}\}">E</figure-callout>}}_{3k}(i,j)+E_{4k}(i,j)]$

Wherein, E _3k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance beam radia of continental rise platform; E _4k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance menology diffuse reflection radiation of continental rise platform; Centre coordinate according to illumination geometric parameter, observation geometric parameter, continental rise platform parameter, menology reflectivity parameter and visual field pixel, utilizes the definition of irradiance, E _3k(i, j) and E _4k(i, j) is expressed as:

${\mathrm{<figure-callout\; id="3k"\; label="E"\; filenames="HDA0000403721720000021.png"\; state="\{\{state\}\}">E</figure-callout>}}_{3k}(i,j)=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}{\mathrm{\&rho;}}_d\cos {{\mathrm{\&theta;}}^{\&prime;}}_k\underset{{\mathrm{\&Sigma;}}_{\mathrm{ik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, d ∑ is continental rise platform k surperficial ∑ _kcell area; θ _2kbe the line of cell area d ∑ and visual field (i, j) pixel and the angle of z axle positive dirction, get acute angle; θ _3kline and the ∑ of cell area d ∑ and visual field (i, j) pixel _kthe angle of surface normal, gets acute angle; L is the distance of the line of cell area d ∑ and visual field (i, j) pixel; θ ' _kit is ∑ _kthe supplementary angle of surface normal direction and solar incident ray angular separation; ρ _dit is platform diffuse reflectance; Integral domain ∑ _ikit is ∑ _kthe region that surface is illuminated by beam radia;

$E_{4k}(i,j)=\frac{1}{\mathrm{\&pi;}}{\mathrm{\&rho;}}_d\underset{{\mathrm{\&Sigma;}}_k}{\&Integral;}\frac{E_{\mathrm{kp}}\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, E _kpcontinental rise platform k surperficial ∑ _kthe menology diffuse reflection irradiance that receives of cell area d ∑ be expressed as:

$E_{\mathrm{kp}}=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}\mathrm{\&rho;}\cos \mathrm{\&theta;}\underset{{\mathrm{\&Sigma;}}_{\mathrm{aik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{4k}\cos {\mathrm{\&theta;}}_{5k}}{{l_1}^2}d{\mathrm{\&Sigma;}}_l$

Wherein, d ∑ _lit is menology cell area; θ _4kit is d ∑ _lwith the line of cell area d ∑ and the angle of z axle positive dirction on k surface of continental rise platform, get acute angle; θ _5kit is d ∑ _lline and ∑ with d ∑ _kthe angle of surface normal, gets acute angle; l ₁cell area d ∑ and cell area d ∑ _lthe distance of line; Integral domain ∑ _aikthat menology is illuminated the region that menology diffuse light in region can illuminate d ∑; ρ is menology diffuse reflectance.

Wherein, " generating the simulation entrance pupil spoke brightness cube of continental rise imaging spectrometer " described in step (7), its implication is: the entrance pupil spoke brightness of continental rise imaging spectrometer comprises: diffuse reflection beam radia in menology visual field enters the spoke brightness of imaging spectrometer, the mirror-reflection radiation of menology visual field diffuse reflection continental rise platform enters the spoke brightness that the spoke brightness of imaging spectrometer and the diffuse reflection radiation of menology visual field diffuse reflection continental rise platform enter imaging spectrometer, in visual field, ranks number are (i, the entrance pupil spoke brightness L (i, j) of pixel j) can be expressed as:

$L(i,j)=\frac{\mathrm{\&rho;}}{\mathrm{\&pi;}}[E_0(i,j)+E_1(i,j)+E_2(i,j)]$

Wherein, E ₀(i, j) is the irradiance of the beam radia that receives of pixel that in visual field, ranks number are (i, j); E ₁(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives the radiation of continental rise platform mirror-reflection; E ₂(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives continental rise platform diffuse reflection radiation; ρ is menology diffuse reflectance.

The present invention's advantage is compared with prior art: the present invention provides the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology, simulation process is considered shade and the impact of reflected radiation on imaging data of continental rise platform, make its actual physical process that meets the imaging of menology continental rise imaging spectrometer, improved the authenticity of simulated data.The simulated data generating can be used for: the optimum observed pattern of (1) design continental rise imaging spectrometer; (2) in process of data preprocessing, reject the impact of continental rise platform, improve the quality of data.

(4) accompanying drawing explanation

Fig. 1 is implementation method process flow diagram of the present invention.

Fig. 2 (a) is that menology of the present invention visual field receives continental rise platform diffuse reflection radiation schematic diagram;

Fig. 2 (b) is that continental rise platform of the present invention receives menology diffuse reflection radiation schematic diagram.

(5) embodiment

As shown in Figure 1, specific embodiment of the invention method is as follows:

1, analog parameter is set

Set illumination geometric parameter, observation geometric parameter, continental rise platform parameter, continental rise imaging spectral instrument parameter and menology reflectivity data cube, wherein, illumination geometric parameter comprises: sun altitude and solar azimuth; Observation geometric parameter comprises: observation zenith angle and observed azimuth; Continental rise platform parameter comprises: the Reflectivity Model of the three-dimensional profile structure of continental rise platform, each surperficial size and continental rise platform surface; Continental rise imaging spectral instrument parameter comprises: the space dimension ranks pixel numbers (m, n) of the three-dimensional position relation of the three-dimensional profile structure of continental rise imaging spectrometer and size, continental rise imaging spectrometer and continental rise platform, field angle and each imaging; The cubical space of menology reflectivity data dimension ranks number is m * n;

2, set up continental rise platform coordinate system

Take continental rise platform bottom center is initial point in the vertical projection of menology, and sky, the northeast coordinate system at initial point place is rotated around celestial axis

angle, obtains continental rise platform coordinate system, and the east of sky, northeast coordinate system, north, celestial axis is corresponding to the x, y, z axle of continental rise platform coordinate system, and wherein, against turning axle, see and be rotated counterclockwise as just, for observed azimuth.In menology coordinate system, the direction vector of incident ray is α, and it is α that the direction vector of this incident ray transforms to continental rise platform coordinate _p, be expressed as:

${\mathrm{\&alpha;}}_p=\mathrm{T\&alpha;}=\left(\begin{array}{ccc}\cos (-\mathrm{\&psi;})& \sin (-\mathrm{\&psi;})& 0\\ -\sin (-\mathrm{\&psi;})& \cos (-\mathrm{\&psi;})& 0\\ 0& 0& 1\end{array}\right)\left[\begin{array}{c}{\mathrm{\&alpha;}}_1\\ {\mathrm{\&alpha;}}_2\\ {\mathrm{\&alpha;}}_3\end{array}\right]$

Wherein, T is the transformation matrix that menology coordinate is tied to continental rise platform coordinate system.

3, calculate the centre coordinate of visual field pixel

According to the three-dimensional coordinate at how much of observations and spectrometer entrance pupil place, the centre coordinate of the menology visual field that is easy to get, by the field angle of spectrometer, can obtain the four angular coordinate of menology visual field, think that the physical dimension of all pixels is identical, by the ranks number of each imaging, centre coordinate that can all pixels.

The irradiance of the beam radia that 4, calculating visual field receives

(1) according to the centre coordinate of how much of illumination, continental rise platform parameter and visual field pixel, calculate the scope being covered by shade in menology visual field, generate visual field shadow matrix S, comprise the following steps:

1. to a certain surperficial ∑ of continental rise platform _k, calculate ∑ _kthe projection at menology along illumination geometric direction of each summit, obtain ∑ _kthe shadow region ∑ producing at menology _kS, generate m * n dimension null matrix S _k, to ranks number, be the visual field pixel of (i, j), connect this pixel and ∑ _kSeach summit, calculate this pixel and ∑ _kSthe included angle of each adjacent vertex _pif,

this pixel is in shadow region ∑ _kSin, make S _k(i, j)=0, otherwise, S made _k(i, j)=1, all does above-mentioned calculating to each pixel of visual field, judges that whether it is in shadow region ∑ _kSin, effects on surface ∑ _k, generate visual field shadow matrix S _k;

2. 1. each surface of continental rise platform is all calculated by step, generate corresponding menology shade scope and visual field shadow matrix, the menology shade scope ∑ that whole continental rise platform produces _sbe expressed as:

${\mathrm{\&Sigma;}}_S=\underset{k}{\mathrm{\&cup;}}{\mathrm{\&Sigma;}}_{\mathrm{kS}},$

Visual field shadow matrix S is expressed as:

$S(i,j)=\underset{k}{\mathrm{\&Pi;}}{S}_k(i,j);$

(2) in visual field, ranks number are the irradiance E of the beam radia that receives of the pixel of (i, j) ₀be expressed as:

E ₀(i，j)＝E _sunS(i，j)cosθ

Wherein, E _sunbe that the menology sun vertically irradiates irradiance, can use the outer solar irradiance value of earth atmosphere; θ is solar zenith angle; S is visual field shadow matrix.

The irradiance of the continental rise platform mirror-reflection beam radia that 5, calculating visual field receives

(1), according to the centre coordinate of how much of illumination, continental rise platform parameter and visual field pixel, calculate each pixel in visual field and receive a certain surperficial ∑ of continental rise platform _kthe irradiance of mirror-reflection, comprises the following steps:

1. calculate following criterion A and criterion B and whether set up simultaneously, if set up simultaneously, surperficial ∑ _kmirror-reflection radiation may enter visual field, continue step 2., otherwise in visual field, each pixel receives continental rise platform surface ∑ _kthe irradiance of mirror-reflection radiation is zero, directly proceeds to step (2);

Criterion A: gauging surface ∑ _knormal direction and the angle α of z axle positive dirction, judgement

whether set up;

Criterion B: by surperficial ∑ _kexpansion, obtains ∑ _kthe intersection l of place plane and menology _k, ∑ _ksurface normal is n in the vertical projection of menology _k, cross Si Ge summit, visual field respectively to l _kdo vertical line, obtain four corresponding intersection points, connect respectively four summits and corresponding intersection point, obtain four vectors, vector direction is that its corresponding intersection point is pointed on summit, visual field, calculates respectively four vectors and n _kangle γ _i, judgement whether set up;

2. the pixel that to calculate ranks in visual field number be (i, j) receives surperficial ∑ _kthe irradiance E of mirror-reflection beam radia _1k(i, j), comprises following steps:

I. calculate ∑ _kthe supplementary angle θ of surface minute surface reflection ray and menology normal angle _1k;

Ii. calculate continental rise platform at surperficial ∑ _kthe shade ∑ producing _kpS, surperficial ∑ _kthe region ∑ being illuminated by solar radiation _ikbe expressed as:

∑ _ik＝∑ _k-∑ _kpS；

If ∑ iii. _ik=0, surperficial ∑ _kcan not be illuminated E _1k=0; If ∑ _ik≠ 0, ∑ _ikmirror-reflection radiation illuminate the region ∑ of menology _iklcan be by ∑ _iksummit along the intersection point of mirror-reflection light and menology, try to achieve, generate m * n dimension null matrix M _k, to ranks number, be the visual field pixel of (i, j), connect this pixel and ∑ _ikleach summit, calculate this pixel and ∑ _iklthe included angle of each adjacent vertex _qif, this pixel is in areas of specular reflection ∑ _iklin, make M _k(i, j)=1, otherwise, M made _k(i, j)=0, all does above-mentioned calculating to each pixel of visual field, judges that whether it is in areas of specular reflection ∑ _iklin, to ∑ _ksurface, generates visual field mirror reflecting matrix M _k.

IV. in visual field, ranks number are that the pixel of (i, j) receives surperficial ∑ _kthe irradiance E of mirror-reflection beam radia _1k(i, j) is expressed as:

E ₁(i，j)＝E _sunρ _MM _k(i，j)cosθ _1k

Wherein, ρ _mit is continental rise platform specular reflectance; M _kit is ∑ _kthe mirror reflecting matrix on surface; θ _1kit is ∑ _kthe supplementary angle of surface minute surface reflection ray and menology normal angle;

(2) each surface of continental rise platform is all calculated by step (1), in visual field, ranks number are that the pixel of (i, j) receives continental rise platform mirror-reflection irradiance E ₁(i, j) is expressed as:

$E_1(i,j)=\underset{k}{\mathrm{\&Sigma;}}{E}_{1k}(i,j)$

Wherein, E _1k(i, j) is that the pixel that in visual field, ranks number are (j, j) receives surperficial ∑ _kthe irradiance of mirror-reflection beam radia.

The irradiance of the continental rise platform diffuse reflection radiation that 6, calculating visual field receives

(1), according to the centre coordinate of how much of illumination, continental rise platform parameter and visual field pixel, calculate each pixel in visual field and receive a certain surperficial ∑ of continental rise platform _kthe irradiance of diffuse reflection radiation, comprises the following steps:

1. in step 5, if effects on surface ∑ _k, criterion A and criterion B set up simultaneously, surperficial ∑ _kdiffuse reflection radiation can enter visual field, continue calculation procedure 2., otherwise in visual field, each pixel receives continental rise platform ∑ _kthe irradiance of surface diffuse reflectance radiation is zero, directly proceeds to step (2);

2. ∑ step 5 being calculated _ikif, ∑ _ik=0, surperficial ∑ _kcan not be illuminated E _3k=0; If ∑ _ik≠ 0, as shown in Fig. 2 (a), in visual field, ranks number are that the pixel of (j, j) receives surperficial ∑ _kthe irradiance E of diffuse reflection beam radia _3k(i, j) is expressed as:

${\mathrm{<figure-callout\; id="3k"\; label="E"\; filenames="HDA0000403721720000021.png"\; state="\{\{state\}\}">E</figure-callout>}}_{3k}(i,j)=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}{\mathrm{\&rho;}}_d\cos {{\mathrm{\&theta;}}^{\&prime;}}_k\underset{{\mathrm{\&Sigma;}}_{\mathrm{ik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, d ∑ is continental rise platform k surperficial ∑ _kcell area; θ _2kbe the line of cell area d ∑ and visual field (i, j) pixel and the angle of z axle positive dirction, get acute angle; θ _3kline and the ∑ of cell area d ∑ and visual field (i, j) pixel _kthe angle of surface normal, gets acute angle; L is the distance of the line of cell area d ∑ and visual field (i, j) pixel; θ ' _kit is ∑ _kthe supplementary angle of surface normal direction and solar incident ray angular separation; ρ _dit is platform diffuse reflectance; Integral domain ∑ _ikit is ∑ _kthe region that surface is illuminated by beam radia;

3. the pixel that to calculate ranks in visual field number be (j, j) receives surperficial ∑ _kthe irradiance E of diffuse reflection menology diffuse reflection radiation _3k(i, j), comprises following steps:

I. define effective half-plane ∑ _afor the l with in step 5 criterion B _kfor boundary, ∑ _ksurface normal is n in the vertical projection of menology _kthe half-plane of pointing direction, the scope ∑ that effectively half-plane is illuminated _aikbe expressed as:

∑ _aik＝∑ _a-(∑ _a∩∑ _S)

Wherein, ∑ _ait is effective half-plane; ∑ _sit is the shadow region that continental rise platform produces at menology;

Ii. according to irradiance, define, as shown in Fig. 2 (b), continental rise platform surface ∑ _kmiddle cell area d ∑ receives the irradiance E of menology diffuse reflection radiation _kpbe expressed as:

$E_{\mathrm{kp}}=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}\mathrm{\&rho;}\cos \mathrm{\&theta;}\underset{{\mathrm{\&Sigma;}}_{\mathrm{aik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{4k}\cos {\mathrm{\&theta;}}_{5k}}{{l_1}^2}d{\mathrm{\&Sigma;}}_l$

Wherein, d ∑ _lit is menology cell area; θ _4kit is d ∑ _lwith the line of cell area d ∑ and the angle of z axle positive dirction on k surface of continental rise platform, get acute angle; θ _5kit is d ∑ _lline and ∑ with d ∑ _kthe angle of surface normal, gets acute angle; l ₁cell area d ∑ and cell area d ∑ _lthe distance of line; Integral domain ∑ _aikthat menology is illuminated the region that menology diffuse light in region can illuminate d ∑; ρ is menology diffuse reflectance.

Iii. in visual field, ranks number are that the pixel of (i, j) receives ∑ _kthe irradiance E of surface diffuse reflectance menology diffuse reflection radiation _4k(i, j) is expressed as:

$E_{4k}(i,j)=\frac{1}{\mathrm{\&pi;}}{\mathrm{\&rho;}}_d\underset{{\mathrm{\&Sigma;}}_k}{\&Integral;}\frac{E_{\mathrm{kp}}\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, E _kpcontinental rise platform k surperficial ∑ _kthe menology diffuse reflection irradiance that receives of cell area d ∑;

(2) each surface of continental rise platform is all calculated by step (1), in visual field, ranks number are that the pixel of (i, j) receives continental rise platform diffuse reflection irradiance E ₂(i, j) is expressed as:

$E_2(i,j)=\underset{k}{\mathrm{\&Sigma;}}[{\mathrm{<figure-callout\; id="3k"\; label="E"\; filenames="HDA0000403721720000021.png"\; state="\{\{state\}\}">E</figure-callout>}}_{3k}(i,j)+E_{4k}(i,j)]$

Wherein, E _3k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance beam radia of continental rise platform; E _4k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance menology diffuse reflection radiation of continental rise platform.

7, generate the simulation entrance pupil spoke brightness cube of continental rise imaging spectrometer

The entrance pupil spoke brightness of continental rise imaging spectrometer comprises: diffuse reflection beam radia in menology visual field enters the spoke brightness of imaging spectrometer, the mirror-reflection radiation of menology visual field diffuse reflection continental rise platform enters the spoke brightness that the spoke brightness of imaging spectrometer and the diffuse reflection radiation of menology visual field diffuse reflection continental rise platform enter imaging spectrometer, in visual field, ranks number are (i, the entrance pupil spoke brightness L (i, j) of pixel j) can be expressed as:

$L(i,j)=\frac{\mathrm{\&rho;}}{\mathrm{\&pi;}}[E_0(i,j)+E_1(i,j)+E_2(i,j)]$

Wherein, E ₀(i, j) is the irradiance of the beam radia that receives of pixel that in visual field, ranks number are (i, j); E ₁(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives the radiation of continental rise platform mirror-reflection; E ₂(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives continental rise platform diffuse reflection radiation; ρ is menology diffuse reflectance.

Finally obtain under smooth menology environment the simulation entrance pupil spoke brightness data of continental rise imaging spectrometer.

Claims (6)

1. an analogy method for continental rise imaging spectrometer entrance pupil spoke brightness data under smooth menology, is characterized in that: it comprises following steps:

(1) set illumination geometric parameter, observation geometric parameter, continental rise platform parameter, continental rise imaging spectral instrument parameter and menology reflectivity data cube, wherein, illumination geometric parameter comprises: sun altitude and solar azimuth; Observation geometric parameter comprises: observation zenith angle and observed azimuth; Continental rise platform parameter comprises: the Reflectivity Model of the three-dimensional profile structure of continental rise platform, each surperficial size and continental rise platform surface; Continental rise imaging spectral instrument parameter comprises: the space dimension ranks pixel numbers (m, n) of the three-dimensional position relation of the three-dimensional profile structure of continental rise imaging spectrometer and size, continental rise imaging spectrometer and continental rise platform, field angle and each imaging; The cubical space of menology reflectivity data dimension ranks number is m * n;

(2) set up continental rise platform coordinate system, and illumination geometric parameter in step (1) is transformed to continental rise platform coordinate system, calculate all in continental rise platform coordinate system later;

(3), according to the continental rise imaging spectral instrument parameter of setting in step (1), observation geometric parameter, calculate the centre coordinate of continental rise imaging spectrometer each pixel in menology visual field;

(4), according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the beam radia that in visual field, each pixel receives;

(5) according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the continental rise platform mirror-reflection radiation that in visual field, each pixel receives;

(6) according to the centre coordinate of each pixel in the menology visual field of calculating in the continental rise platform parameter of setting in step (1), illumination geometric parameter, observation geometric parameter and step (3), calculate the irradiance of the continental rise platform diffuse reflection radiation that in visual field, each pixel receives;

(7) generate the simulation entrance pupil spoke brightness cube of continental rise imaging spectrometer.

2. the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology according to claim 1, it is characterized in that: the continental rise platform coordinate system described in step (2) refers to that take continental rise platform bottom center is initial point in the vertical projection of menology, rotates sky, the northeast coordinate system at initial point place around celestial axis

angle, obtains continental rise platform coordinate system, and the east of sky, northeast coordinate system, north, celestial axis is corresponding to the x, y, z axle of continental rise platform coordinate system, and wherein, against turning axle, see and be rotated counterclockwise as just, for observed azimuth.

3. the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology according to claim 1, it is characterized in that: " the calculating the irradiance of the beam radia that in visual field, each pixel receives " described in step (4), its concrete operations are: according to the centre coordinate of illumination geometric parameter, observation geometric parameter, continental rise platform parameter and visual field pixel, calculate the scope being covered by continental rise platform shade in menology visual field, generate visual field shadow matrix S, in visual field, ranks number are the irradiance E of the beam radia that receives of the pixel of (i, j) ₀be expressed as:

E ₀(i，j)＝E _sunS(i，j)cosθ

Wherein, E _sunbe that the menology sun vertically irradiates irradiance, can use the outer solar irradiance value of earth atmosphere; θ is solar zenith angle; S is visual field shadow matrix, if ranks number are that the pixel of (i, j) is covered by continental rise platform shade in visual field, and S (i, j)=0, otherwise S (i, j)=1.

4. the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology according to claim 1, it is characterized in that: " the calculating the irradiance of the continental rise platform mirror-reflection radiation that in visual field, each pixel receives " described in step (5), its concrete operations are: according to the centre coordinate of illumination geometric parameter, observation geometric parameter, continental rise platform parameter and visual field pixel, calculate the scope being illuminated by continental rise platform k surperficial mirror-reflection in menology visual field, generate visual field mirror reflecting matrix M _k, in visual field, ranks number are the irradiance E of the platform mirror-reflection radiation that receives of the pixel of (i, j) ₁be expressed as:

$E_1(i,j)=\underset{k}{\mathrm{\&Sigma;}}{E}_{\mathrm{sun}}{\mathrm{\&rho;}}_M{M}_k(i,j)\cos {\mathrm{\&theta;}}_{1k}$

Wherein, θ _1kit is the supplementary angle of continental rise platform k surperficial minute surface reflection ray and menology normal angle; ρ _mit is continental rise platform specular reflectance; M _kthe visual field mirror reflecting matrix on k, corresponding continental rise platform surface, if ranks number be that the pixel of (i, j) is illuminated by k surperficial mirror-reflection of continental rise platform in visual field, M _k(i, j)=1, otherwise M _k(i, j)=0.

5. the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology according to claim 1, it is characterized in that: " the calculating the irradiance of the continental rise platform diffuse reflection radiation that in visual field, each pixel receives " described in step (6), its concrete operations are: the irradiance E of the continental rise platform diffuse reflection radiation that the pixel that in visual field, ranks number are (i, j) receives ₂be expressed as:

$E_2(i,j)=\underset{k}{\mathrm{\&Sigma;}}[E_{3k}(i,j)+E_{4k}(i,j)]$

Wherein, E _3k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance beam radia of continental rise platform; E _4k(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives k surface diffuse reflectance menology diffuse reflection radiation of continental rise platform; Centre coordinate according to illumination geometric parameter, observation geometric parameter, continental rise platform parameter, menology reflectivity parameter and visual field pixel, utilizes the definition of irradiance, E _3k(i, j) and E _4k(i, j) is expressed as:

$E_{3k}(i,j)=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}{\mathrm{\&rho;}}_d\cos {{\mathrm{\&theta;}}^{\&prime;}}_k\underset{{\mathrm{\&Sigma;}}_{\mathrm{ik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, d ∑ is continental rise platform k surperficial ∑ _kcell area; θ _2kbe the line of cell area d ∑ and visual field (i, j) pixel and the angle of z axle positive dirction, get acute angle; θ _3kline and the ∑ of cell area d ∑ and visual field (i, j) pixel _kthe angle of surface normal, gets acute angle; L is the distance of the line of cell area d ∑ and visual field (i, j) pixel; θ ' _kit is ∑ _kthe supplementary angle of surface normal direction and solar incident ray angular separation; ρ _dit is platform diffuse reflectance; Integral domain ∑ _ikit is ∑ _kthe region that surface is illuminated by beam radia;

$E_{4k}(i,j)=\frac{1}{\mathrm{\&pi;}}{\mathrm{\&rho;}}_d\underset{{\mathrm{\&Sigma;}}_k}{\&Integral;}\frac{E_{\mathrm{kp}}\cos {\mathrm{\&theta;}}_{2k}\cos {\mathrm{\&theta;}}_{3k}}{l^2}\mathrm{d\&Sigma;}$

Wherein, E _kpcontinental rise platform k surperficial ∑ _kthe menology diffuse reflection irradiance that receives of cell area d ∑, be expressed as:

$E_{\mathrm{kp}}=\frac{1}{\mathrm{\&pi;}}{E}_{\mathrm{sun}}\mathrm{\&rho;}\cos \mathrm{\&theta;}\underset{{\mathrm{\&Sigma;}}_{\mathrm{aik}}}{\&Integral;}\frac{\cos {\mathrm{\&theta;}}_{4k}\cos {\mathrm{\&theta;}}_{5k}}{{l_1}^2}d{\mathrm{\&Sigma;}}_l$

Wherein, d ∑ _lit is menology cell area; θ _4kit is d ∑ _lwith the line of cell area d ∑ and the angle of z axle positive dirction on k surface of continental rise platform, get acute angle; θ _5kit is d ∑ _lline and ∑ with d ∑ _kthe angle of surface normal, gets acute angle; l ₁cell area d ∑ and cell area d ∑ _lthe distance of line; Integral domain ∑ _aikthat menology is illuminated the region that menology diffuse light in region can illuminate d ∑.

6. the analogy method of continental rise imaging spectrometer entrance pupil spoke brightness data under a kind of smooth menology according to claim 1, it is characterized in that: " the generating the simulation entrance pupil spoke brightness cube of continental rise imaging spectrometer " described in step (7), its implication is: the entrance pupil spoke brightness of continental rise imaging spectrometer comprises: diffuse reflection beam radia in menology visual field enters the spoke brightness of imaging spectrometer, the mirror-reflection radiation of menology visual field diffuse reflection continental rise platform enters the spoke brightness that the spoke brightness of imaging spectrometer and the diffuse reflection radiation of menology visual field diffuse reflection continental rise platform enter imaging spectrometer, in visual field, ranks number are (i, the entrance pupil spoke brightness L (i of pixel j), j) can be expressed as:

$L(i,j)=\frac{\mathrm{\&rho;}}{\mathrm{\&pi;}}[E_0(i,j)+E_1(i,j)+E_2(i,j)]$

Wherein, E ₀(i, j) is the irradiance of the beam radia that receives of pixel that in visual field, ranks number are (i, j); E ₁(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives the radiation of continental rise platform mirror-reflection; E ₂(i, j) is the irradiance that pixel that in visual field, ranks number are (i, j) receives continental rise platform diffuse reflection radiation; ρ is menology diffuse reflectance.

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