A method for calculating the sun elevation angle of a multi-view axis reference

Abstract

The present application relates to the technical field of satellite, in particular to a kind of solar elevation angle calculation method of multi-view axis reference.The view axis is executed for each view axis, and reference coordinate system of view axis is constructed;According to the current attitude of the satellite carrying the view axis and the reference coordinate system of the view axis, the attitude of the view axis under the reference coordinate system is calculated;According to the scaling matrix of the earth ellipsoid under the inertial system, the satellite position vector under the inertial system, the attitude of the view axis under the reference coordinate system, the conversion matrix from the inertial system to the orbital system and the earth radius, the distance vector from the center of the earth to the view axis pointing point in the inertial system is determined;According to the distance vector from the center of the earth to the view axis pointing point in the inertial system, the scaled vector from the center of the earth to the view axis under the inertial system and the unit vector of the sun under the inertial system, the solar elevation angle of the view axis pointing point is determined.The present application can simultaneously accurately calculate the solar elevation angle for multi-view axis reference.

Description

Technical Field

[0001] This invention relates to the field of satellite technology, and in particular to a method for calculating the solar altitude angle based on multiple line-of-sight references. Background Technology

[0002] Because satellite payloads contain multiple lines of sight, each pointing to a different point, their corresponding solar altitude angles also differ. Currently, there is no method for remote sensing satellites in orbit to accurately calculate the solar altitude angle simultaneously for multiple lines of sight. Summary of the Invention

[0003] This invention provides a method, apparatus, electronic device, and storage medium for calculating the solar altitude angle based on multiple viewing axes, enabling the simultaneous and accurate calculation of the solar altitude angle for multiple viewing axes.

[0004] In a first aspect, embodiments of the present invention provide a method for calculating the solar altitude angle based on a multi-axis reference, comprising:

[0005] For each view axis, execute:

[0006] Construct a reference coordinate system for the line of sight;

[0007] Based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight, calculate the attitude of the line of sight in the reference coordinate system;

[0008] Based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth radius, determine the distance vector from the Earth's center to the point pointed to by the line of sight in the inertial frame;

[0009] The solar altitude angle of the point pointing to the line of sight is determined based on the distance vector from the geocenter to the point pointed to by the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame.

[0010] Secondly, embodiments of the present invention also provide a solar altitude angle calculation device based on a multi-axis reference, used to implement any of the above methods, the device comprising:

[0011] Construction unit, used to construct the reference coordinate system for the view axis;

[0012] An attitude determination unit is used to calculate the attitude of the line of sight in the reference coordinate system based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight.

[0013] The distance vector unit is used to determine the distance vector from the Earth's center to the point pointed to by the line of sight in the inertial frame based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth's radius.

[0014] The elevation angle calculation unit is used to determine the solar elevation angle of the line of sight pointing to the point based on the distance vector from the geocenter to the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame.

[0015] Thirdly, embodiments of the present invention also provide an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, it implements the method described in any embodiment of this specification.

[0016] Fourthly, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the methods described in any embodiment of this specification.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects:

[0018] The method proposed in this invention is applicable to remote sensing payloads of any installation type and any number of line-of-sight (LOS) pointing. Using the same algorithm, parallel computation can simultaneously and with high precision calculate the solar elevation angle of multiple LOS. Specifically, a reference coordinate system for the LOS is first constructed. Then, the attitude of the LOS in the reference coordinate system is determined based on the reference coordinate system and the current satellite attitude. Based on the obtained LOS attitude, Earth ellipsoid scaling matrix, inertial frame satellite position vector, the LOS attitude in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth radius, the distance vector from the Earth's center to the LOS pointing point in the inertial frame can be determined. The solar elevation angle of the LOS pointing point is determined based on the distance vector from the Earth's center to the LOS pointing point in the inertial frame, the scaled vector from the Earth's center to the LOS in the inertial frame, and the unit vector of the Sun in the inertial frame. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A graph showing the variation of solar altitude angle across five axes within one orbital period;

[0021] Figure 2 This is a magnified view of the changes in solar altitude angle across the five axes of sight. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] The following describes the specific implementation of the above concept.

[0024] Please refer to Figure 1 This invention provides a method for calculating the solar altitude angle using a multi-axis reference, comprising:

[0025] For each view axis, execute:

[0026] S1, construct the reference coordinate system for the line of sight;

[0027] S2, calculate the attitude of the line of sight in the reference coordinate system based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight;

[0028] S3. Based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth radius, determine the distance vector from the Earth's center to the point pointed to by the line of sight in the inertial frame.

[0029] S4. Determine the solar altitude angle of the line of sight pointing to the point based on the distance vector from the geocenter to the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame.

[0030] Specifically, for S1, this includes determining the off-field angle of each of the multiple axes of view based on the load imaging principle. θ i ;in: Let θ be the off-center angle along the X-axis for each line of sight. i The field angle in the Y-axis direction for each view axis is denoted by , and the subscript i represents the i-th view axis.

[0031] Construct the reference coordinate system for each line of sight:

[0032]

[0033] Among them, C sbiFor each line of sight reference coordinate system, Angle2DCM is the function for transforming attitude angles into attitude matrices, which is a technique known to those skilled in the art, and 123 is the attitude angle conversion.

[0034] For S2, this specifically includes calculating the attitude of each line-of-sight reference coordinate system based on the satellite's current attitude:

[0035] C soi =C sbi *C bo ;

[0036] Where: C bo For the current attitude of the satellite, C soi The attitude of each line of sight reference coordinate system.

[0037] S3 includes:

[0038] S301. Based on the Earth ellipsoid scaling matrix and the satellite position vector in the inertial frame, determine the scaled satellite position vector in the inertial frame.

[0039] S302, based on the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the scaling matrix of the Earth ellipsoid in the inertial frame, determine the scaling unit vector of the line of sight pointing in the scaled inertial frame;

[0040] S303, Based on the unit vector of the scaling system and the position vector of the satellite in the scaled inertial frame, determine the angle between the line connecting the satellite to the Earth's center and the vector pointing to the line of sight.

[0041] S304. Based on the magnitude of the satellite position vector, the included angle, the transformation matrix from the inertial frame to the orbital frame, the Earth's radius, and the scaling matrix of the Earth ellipsoid in the inertial frame, determine the distance vector from the Earth's center to the point pointing to the line of sight in the inertial frame.

[0042] The Earth ellipsoid scaling matrix in the inertial frame is determined by the following method:

[0043] CpnT = MatTrans(Cpn);

[0044] C_i_I_new = Cpn*CiI*CpnT;

[0045] Where C_i_I_new is the Earth ellipsoid scaling matrix in the inertial frame, CiI is the Earth ellipsoid scaling matrix, which is a constant, MatTrans is the matrix transpose function, Cpn is the Earth's precession nutation matrix, which has a definite value for a specific time, and CpnT is the transpose of the precession nutation matrix.

[0046] Step S301 is achieved through the following formula:

[0047] r_s_i = C_i_I_new * r_s_I;

[0048] Where C_i_I_new is the Earth ellipsoid scaling matrix in the inertial frame, r_s_I is the satellite position vector in the inertial frame, and r_s_i is the satellite position vector in the scaled inertial frame.

[0049] Step S302 is achieved through the following formula:

[0050] s i =[C soi (3,1); C soi (3,2); C soi (3,3)];

[0051] CoiT = MatTrans(Coi);

[0052] r_Zb_e_i i =C_i_I_new*CoiT*s i ;

[0053] Among them, C soi Let C be the attitude matrix of the line of sight in the reference coordinate system. soi (3,1) is matrix C soi The element in the third row and first column, C soi (3,2) is matrix C soi The element in the third row and second column, C soi (3,3) is matrix C soi The elements in the third row and third column are: Coi, which is the transformation matrix from the inertial frame to the orbital frame, determined by the satellite's current orbit; CoiT, which is the transpose of the transformation matrix from the inertial frame to the orbital frame; and s. i Let r_Zb_e_i be the unit vector pointing to the i-th line of sight in the orbital frame. i Let be the scaling unit vector pointing to the i-th view axis in the scaled inertial frame.

[0054] Step S303 is achieved through the following formula:

[0055] nr_s_i = norm(r_s_i, 3);

[0056] nr_Zb_e_i i =norm(r_Zb_e_i i ,3);

[0057] cosγm i =-dot(r_s_i,r_Zb_e_i) i ,3) / nr_s_i / r_Zb_e_i i ;

[0058] Where nr_s_i is the magnitude of the satellite position vector, norm is the function for taking the magnitude of the vector, and nr_Zb_e_i i Let cosγm be the magnitude of the Z-axis in each viewpoint coordinate system. i The angle between the vector from the satellite to the Earth's center and the vector pointing to the line of sight.

[0059] Step S304 is achieved through the following formula:

[0060] sin2γm i =1-cosγm i *cosγm i ;

[0061] nr_Zb_i i =nr_s_i*cosγm i -sqrt(Re 2 -nr_s_i 2 *sin2γm i );

[0062]

[0063] Wherein sin2γm i nr_Zb_i is an intermediate variable. i R_e_I represents the magnitude of the distance from the satellite to each line-of-sight pointing point in the inertial frame. i Let Re be the distance vector from the Earth's center to the point to which the line of sight points in the inertial frame, and let Re be the Earth's radius.

[0064] Step S4 is achieved through the following formula:

[0065]

[0066] Among them, N_ES i Let V_NeSS be the vector from the geocenter to each line of sight in the scaled inertial frame. Orb.Six, Orb.Siy, and Orb.Siz are the three components of the unit vector of the solar vector in the inertial frame. i For N_ES i The dot product of the solar vector and the unit vector, SolarAltitudeAngle i The solar altitude angle is the angle at which each line of sight points.

[0067] It should be noted that R_e_I i The number in parentheses indicates which element of the vector it is; the numbers 1, 2, and 3 represent the x, y, and z axis components, respectively.

[0068] To better illustrate the beneficial effects of this application, the following specific embodiments are provided.

[0069] Example 1:

[0070] A method for calculating the solar altitude angle based on multiple viewing axes, the specific implementation steps of which are as follows:

[0071] The star orbits in a 500km sun-synchronous orbit;

[0072] The initial orbital elements of the satellite are:

[0073] The semi-long wheelbase is 6842.700 kilometers.

[0074] The track inclination angle is 97.5959 degrees.

[0075] Eccentricity 0.03205

[0076] The right ascension of the ascending node is 73.4813 degrees.

[0077] The perigee argument is 168.4043 degrees.

[0078] True near angle is 67.8351 degrees.

[0079] The satellite payload has five lines of sight. During normal satellite operation, the following steps 2) to 5) are performed simultaneously on each line of sight.

[0080] The off-field angles of each view axis in a multi-view system are determined based on the load imaging principle. θ i ;

[0081] in:

[0082] The X-axis offset angle for each line of sight;

[0083] θ i The offset angle along the Y-axis for each view axis;

[0084] i represents the i-th line of sight;

[0085] The satellite payload has five lines of sight, and the off-field angles of each line of sight are as follows:

[0086] Axis of view 1: θ1 = 0;

[0087] Axis of view 2: degrees, θ2=-3.53 degrees;

[0088] Axis of vision 3: degrees, θ3 = -3.53 degrees;

[0089] Axis of view 4: degrees, θ4 = 3.53 degrees;

[0090] Axis of vision 5: degrees, θ5 = -3.53 degrees;

[0091] Construct the reference coordinate system for each line of sight:

[0092]

[0093] Where C sbi For each line of sight, establish a reference coordinate system;

[0094] Angle2DCM is a function that transforms attitude angles into attitude matrices, a technique well-known to those in the art. 123 represents attitude angle conversion.

[0095] Calculate the attitude of each line-of-sight reference coordinate system based on the satellite's current attitude:

[0096] C soi =C sbi *C bo ;

[0097] in:

[0098] C bo This indicates the satellite's current attitude.

[0099] C soi The attitude of each line of sight reference coordinate system.

[0100] Calculate the satellite's own position vector considering the Earth's ellipsoid:

[0101] CpnT = MatTrans(Cpn);

[0102] C_i_I_new = Cpn*CiI*CpnT;

[0103] r_s_i=C_i_I_new*r_s_I.

[0104] in,

[0105] Cpn is the precession and nutation matrix of the Earth, which has a definite value at a specific time;

[0106] CpnT is the transpose of the precession nutation matrix;

[0107] MatTrans is a matrix transpose function, a technique well-known to those skilled in the art;

[0108] CiI is the Earth ellipsoid scaling matrix, which is a constant;

[0109] C_i_I_new is the scaling matrix of the Earth ellipsoid in the inertial frame;

[0110] r_s_I is the satellite position vector in the inertial frame;

[0111] r_s_i is the satellite position vector in the scaled inertial frame;

[0112] Calculate the vector pointing from the satellite to the ground, taking into account the Earth's ellipsoid:

[0113] s i =[C soi (3,1); C soi (3,2); C soi (3,3)];

[0114] CoiT = MatTrans(Coi);

[0115] r_Zb_e_i i =C_i_I_new*CoiT*s i .

[0116] in,

[0117] C soi (3,1) is matrix C soi The element in the third row and first column;

[0118] C soi (3,2) is matrix C soi The element in the third row and second column;

[0119] C soi (3,3) is matrix C soi The element in the third row and third column;

[0120] Coi is the transformation matrix from the inertial frame to the orbital frame, which can be uniquely determined by the satellite's current orbit;

[0121] CoiT is the transpose of the transformation matrix from inertial frame to orbital frame;

[0122] s i Let be the representation of the unit vector pointing to the i-th line of sight in the orbital frame;

[0123] r_Zb_e_i i Let this be the representation of the unit vector pointing to the i-th line of sight in the scaled inertial frame. Calculate the angle between the vector from the satellite to the Earth's center and the vector pointing to the line of sight:

[0124] nr_s_i = norm(r_s_i, 3);

[0125] nr_Zb_e_i i =norm(r_Zb_e_i i ,3);

[0126] cosγm i=-dot(r_s_i,r_Zb_e_i) i ,3) / nr_s_i / r_Zb_e_i i ;

[0127] in,

[0128] nr_s_i is the magnitude of the satellite position vector;

[0129] norm is a function for taking the modulus of a vector, and is a technique known to those in the art.

[0130] nr_Zb_e_i i The magnitude of the Z-axis for each view axis coordinate system;

[0131] cosγm i The angle between the vectors from the satellite to the Earth's center and the points pointing along each line of sight;

[0132] dot is the vector dot product function, a technique well-known to those in the field.

[0133] Formula for calculating the vector from the Earth's center to the point pointing along the line of sight in an inertial frame:

[0134] sin2γm i =1.0-cosγm i *cosγm i ;

[0135] nr_Zb_i i =nr_s_i*cosγm i -sqrt(Re 2 -nr_s_i 2 *sin2γm i );

[0136]

[0137] in,

[0138] sin2γm i As an intermediate variable;

[0139] nr_Zb_i i This represents the magnitude of the distance from the satellite to each line-of-sight pointing point in the inertial frame.

[0140] R_e_I i This represents the distance vector from the Earth's center to each point indicated by the line of sight in the inertial frame.

[0141] Re is the Earth's radius, which is a constant.

[0142] Calculate the solar altitude angle of each line of sight reference based on the position vector of each line of sight pointing to the ground point:

[0143] in,

[0144] N_ES i This is the scaled representation of the vector from the geocenter to each line of sight in the inertial frame;

[0145] Orb.Six, Orb.Siy, and Orb.Siz are the three components of the unit vector of the solar vector in the inertial frame;

[0146] V_NeSS i For N_ES i The dot product of the solar vector and the unit vector;

[0147] SolarAltitudeAngle i The solar altitude angle is the angle at which each line of sight points.

[0148] Complete the calculation of the solar altitude angle for the multi-axis reference. See the appendix for the variation of the solar altitude angle for each axis. Figure 1 As shown in the enlarged view of the changes in solar altitude angle across the five axes of sight, see the following diagram. Figure 2 As shown.

[0149] This invention provides a solar altitude angle calculation device based on a multi-axis reference. The device can be implemented in software, hardware, or a combination of both. From a hardware perspective, a hardware architecture diagram of the electronic device housing the multi-axis solar altitude angle calculation device provided in this invention includes, in addition to the processor, memory, network interface, and non-volatile memory, other hardware such as a forwarding chip responsible for processing messages. Taking software implementation as an example, as a logical device, it is formed by the CPU of the electronic device reading the corresponding computer program from the non-volatile memory into memory and running it. The multi-axis solar altitude angle calculation device provided in this embodiment includes:

[0150] Construction unit, used to construct the reference coordinate system for the view axis;

[0151] An attitude determination unit is used to calculate the attitude of the line of sight in the reference coordinate system based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight.

[0152] The distance vector unit is used to determine the distance vector from the Earth's center to the point pointed to by the line of sight in the inertial frame based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth's radius.

[0153] The elevation angle calculation unit is used to determine the solar elevation angle of the line of sight pointing to the point based on the distance vector from the geocenter to the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame.

[0154] It is understood that the structures illustrated in the embodiments of the present invention do not constitute a specific limitation on a multi-axis reference solar altitude angle calculation device. In other embodiments of the present invention, a multi-axis reference solar altitude angle calculation device may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0155] The information interaction and execution process between the modules in the above-mentioned device are based on the same concept as the method embodiment of the present invention, and the specific details can be found in the description of the method embodiment of the present invention, and will not be repeated here.

[0156] This invention also provides an electronic device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements a method for calculating the solar altitude angle of a multi-axis reference according to any embodiment of this invention.

[0157] This invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform a method for calculating the solar altitude angle of a multi-axis reference according to any embodiment of this invention.

[0158] Specifically, a system or apparatus equipped with a storage medium may be provided, on which software program code implementing the functions of any of the embodiments described above is stored, and the computer (or CPU or MPU) of the system or apparatus may read and execute the program code stored in the storage medium.

[0159] In this case, the program code read from the storage medium can itself implement the function of any of the above embodiments, and therefore the program code and the storage medium storing the program code constitute part of the present invention.

[0160] Examples of storage media used to provide program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, program code can be downloaded from a server computer via a communication network.

[0161] Furthermore, it should be clear that not only can the program code read by the computer be executed, but also the operating system or other components operating on the computer can be instructed based on the program code to perform some or all of the actual operations, thereby realizing the function of any of the embodiments described above.

[0162] Furthermore, it is understood that the program code read from the storage medium is written to the memory set in the expansion board inserted into the computer or to the memory set in the expansion module connected to the computer. Then, based on the instructions of the program code, the CPU or other components installed on the expansion board or expansion module execute some and all of the actual operations, thereby realizing the function of any of the above embodiments.

[0163] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0164] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media that can store program code, such as ROM, RAM, magnetic disk, or optical disk.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the solar altitude angle based on a multi-axis reference, characterized in that, include: For each view axis, execute: Construct a reference coordinate system for the line of sight; Based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight, calculate the attitude of the line of sight in the reference coordinate system; Based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth radius, determine the distance vector from the Earth's center to the pointing point of the line of sight in the inertial frame. The solar altitude angle of the line of sight is determined based on the distance vector from the geocenter to the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame. The step of determining the distance vector from the Earth's ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth's radius, includes: Based on the Earth ellipsoid scaling matrix in the inertial frame and the satellite position vector in the inertial frame, determine the satellite position vector in the scaled inertial frame; Based on the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the scaling matrix of the Earth ellipsoid in the inertial frame, the scaling unit vector pointing to the line of sight in the scaled inertial frame is determined. Based on the unit vector of the scaling system and the position vector of the satellite in the scaled inertial frame, determine the angle between the line connecting the satellite to the Earth's center and the vector pointing to the line of sight. Based on the magnitude of the satellite position vector, the included angle, the transformation matrix from the inertial frame to the orbital frame, the Earth's radius, and the scaling matrix of the Earth ellipsoid in the inertial frame, determine the distance vector from the Earth's center to the point pointing to the line of sight in the inertial frame; The solar altitude angle of the line of sight is determined based on the distance vector from the geocenter to the point pointed to by the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame, using the following formula: ； ； ； in, This represents the vector from the geocenter to each line of sight in the scaled inertial frame. , , The three components of the unit vector of the solar vector in the inertial frame are: for The dot product of the unit vector with the solar vector. The solar altitude angle at each line of sight. The numbers 1, 2, and 3 in parentheses represent the x, y, and z axis components, respectively.

2. The calculation method according to claim 1, characterized in that, The Earth ellipsoid scaling matrix in the inertial frame is determined by the following method: ； ； in, The scaling matrix of the Earth ellipsoid in the inertial frame. Let be the Earth ellipsoid scaling matrix, be a constant, and MatTrans be the matrix transpose function. This is the precession and nutation matrix of the Earth, which has a definite value at a specific time. This is the transpose of the precession nutation matrix; The scaling of the satellite's position vector in the inertial frame, based on the Earth ellipsoid scaling matrix and the satellite's position vector in the inertial frame, is determined using the following formula: ； in, The scaling matrix of the Earth ellipsoid in the inertial frame. For the inertial frame satellite position vector, This is the satellite position vector in the scaled inertial frame.

3. The calculation method according to claim 1, characterized in that, The determination of the scaling unit vector pointing to the line of sight in the scaled inertial frame, based on the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the scaling matrix of the Earth ellipsoid in the inertial frame, is achieved through the following steps: ； ； ； in, Let the line of sight be the attitude matrix in the reference coordinate system. For matrix The element in the third row and first column, For matrix The element in the third row and second column, For matrix The element in the third row and third column, The transformation matrix from the inertial frame to the orbital frame is determined by the satellite's current orbit. This is the transpose of the transformation matrix from inertial frame to orbital frame. Let be the unit vector pointing to the i-th line of sight in the orbital frame. Let be the scaling unit vector pointing to the i-th view axis in the scaled inertial frame.

4. The calculation method according to claim 3, characterized in that, The angle between the line connecting the satellite to the Earth's center and the vector pointing to the line of sight, determined based on the unit vector in the scaling system and the satellite's position vector in the scaled inertial frame, is achieved using the following formula: ； ； ； in, The magnitude of the satellite position vector. To find the modulus function of a vector, Let Z be the magnitude of the Z-axis in each view coordinate system. The angle between the vector from the satellite to the Earth's center and the vector pointing to the line of sight.

5. The calculation method according to claim 4, characterized in that, The distance vector from the Earth's ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth's radius are determined using the following formula: ； ； ； in, As an intermediate variable, This represents the magnitude of the distance from the satellite to each line-of-sight pointing point in the inertial frame. Let be the distance vector from the geocenter to the point pointed to by the line of sight in the inertial frame. For the Earth's radius, This is the position vector of the inertial frame satellite.

6. A solar altitude angle calculation device based on a multi-axis reference, characterized in that, The apparatus for implementing the method as described in any one of claims 1-5 comprises: Construction unit, used to construct the reference coordinate system for the view axis; An attitude determination unit is used to calculate the attitude of the line of sight in the reference coordinate system based on the current attitude of the satellite carrying the line of sight and the reference coordinate system of the line of sight. The distance vector unit is used to determine the distance vector from the Earth's center to the point pointed to by the line of sight in the inertial frame based on the Earth ellipsoid scaling matrix in the inertial frame, the satellite position vector in the inertial frame, the attitude of the line of sight in the reference coordinate system, the transformation matrix from the inertial frame to the orbital frame, and the Earth's radius. The elevation angle calculation unit is used to determine the solar elevation angle of the line of sight pointing to the point based on the distance vector from the geocenter to the line of sight in the inertial frame, the scaled vector from the geocenter to the line of sight in the inertial frame, and the unit vector of the sun in the inertial frame.

7. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, and the processor, when executing the computer program, implements the method as described in any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the method of any one of claims 1-5.

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