Spacecraft inter-satellite pointing non-common reference parameter calibration method

Abstract

The invention discloses a spacecraft inter-satellite pointing non-common reference parameter calibration method, which comprises the following steps of: constructing an x-axis and y-axis decoupled non-common reference parameter model by adopting a vector synthesis method, representing the x-axis or the y-axis by using an m-axis, and calibrating each axis: measuring a target with a distance of L1, calculating a first synthesis constant deviation theta 1 of the m-axis, and calculating a second synthesis constant deviation theta 2 of the m-axis; the method comprises the following steps: measuring a target with a distance L2 by using an estimated value # imgabs0 # of m, calculating a second synthetic constant deviation theta 2 of an m axis, calculating an estimated value # imgabs1 # of m by using # imgabs2 # and distances L1 and L2, calculating a third synthetic constant deviation theta 3 of the m axis decoupled from the distances, and calculating a second synthetic constant deviation theta 2 of the m axis by using the estimated value # imgabs1 # of m and the estimated value # imgabs1 # of m and the distances L1 and L2. Calculating an estimated value # imgabs6 # of an m-axis angle constant deviation bm by using an estimated value # imgabs3 # of m and a distance L1 and L2 of # imgabs4 # and an estimated value # imgabs5 # of an m-axis third synthetic constant deviation to obtain an estimated value # imgabs6 # of a whole satellite small-range maneuvering certain angle; and obtaining an estimated value of an m-axis angle measurement proportionality coefficient km when the distance is L3, calculating based on # imgabs8 # and # imgabs9 # to obtain estimation of non-common-base position deviation # imgabs10 #, and obtaining parameter estimation decoupled from the distance by utilizing calibration results under two different distances, so as to reduce position constraints of a signal transmitting end and a signal receiving end.

Description

Technical Field

[0001] The invention relates to a spacecraft intersatellite pointing non-common reference parameter calibration method, belonging to the field of spacecraft parameter calibration. Background Art

[0002] Calibration of non-co-referenced parameters for intersatellite spacecraft pointing is a new requirement arising from new applications such as space laser communications. Non-co-reference refers to the situation where signal transmission and reception occur at different locations on the spacecraft, leading to different references for measurement and pointing. For example, in high-precision spacecraft pointing scenarios (such as real-time, high-precision tracking of targets at long distances), measurements may require the use of measurement sensors with a different reference than the primary payload, leading to non-co-referenced primary payload pointing and measurement sensors. Non-co-reference often occurs when the tracking target does not meet illumination conditions or when the signal light transmitter and receiver are mounted far apart. For example, in an unlit area, imaging cannot be performed using a measurement camera mounted coaxially with the signal light, requiring the use of sensors with other designations to measure the target source. Another example is the remote installation of the signal transmitter and receiver in laser communications, a typical non-co-referenced installation scenario. Non-co-referenced parameters can vary due to factors such as on-orbit structural deformation. Therefore, to improve the accuracy of non-co-referenced pointing, non-co-referenced error chain analysis and calibration are necessary during pointing control.

[0003] Traditional calibration of spacecraft structural parameters and datum deviations primarily targets attitude control in inertial space. Calibration parameters primarily involve angular installation parameters. Since these parameters only include angular errors, they can be calibrated using stellar collimation. However, for interstellar pointing, calibration parameters also include positional parameters, which are extremely small relative to distant stars. Therefore, traditional methods relying on stellar calibration are unable to estimate all non-co-basic parameters. Measurements and evaluations of non-cognate sensors in situations such as rendezvous and docking are not directly used as corrections for attitude control. Regarding the spacecraft parameter calibration method, according to investigation and understanding, the currently disclosed existing technologies are as follows: the invention patent with application number 201410810509.6 discloses a satellite calibration method for phased array sensors, which takes the satellite as the reference target and solves the sensor system error by comparing the measurement data with the ephemeris. It does not design related content of non-common reference parameters and inter-satellite calibration. The relevant algorithm cannot estimate the non-common reference deviation parameters, which is quite different from the present invention; the invention patent with application number 201810637264.6 discloses a method for measuring the antenna pointing thermal deformation of a satellite payload star-sensitive integrated installation structure, which mainly considers the use of an optoelectronic autocollimator on the ground to measure the angular error of the thermal deformation on the satellite. Parameter estimation is not performed through integration, and the parameter estimation accuracy is poor. Summary of the Invention

[0004] The technical problem solved by the present invention is: to overcome the shortcomings of the existing technology, and to provide a method for calibrating non-common reference parameters of spacecraft inter-satellite pointing, which uses the calibration results at two different distances to obtain parameter estimates decoupled from the distance, thereby reducing the position constraints of the signal transmitter and the signal receiver.

[0005] The technical solution of the present invention is: a method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft, comprising:

[0006] S1. Use the vector synthesis method to construct a non-common basis parameter model for decoupling the x-axis and y-axis, and list equations to express the relationship between the three types of coefficients that need to be calibrated; use the m-axis to represent the x-axis or y-axis, that is, m∈{x,y}. The coefficients that need to be calibrated for each axis are: angle measurement scale coefficient k m , Angle measurement constant deviation b m , and non-common reference position deviation K m ;

[0007] S2. Measure the target at a distance of L1 and calculate the first synthetic constant deviation θ of the m-axis 1,m Estimated value of

[0008]

[0009] S3. Measure the target at a distance of L2 and estimate the second synthetic constant deviation θ of the m-axis. 2,m Estimated value of

[0010] S4. Utilization As well as the distances L1 and L2, calculate the third synthetic constant deviation θ of the m-axis decoupled from the distance 3,m Estimated value of

[0011] S5. Utilization Distance L1, L2 and m-axis third synthetic constant deviation estimate Calculate the m-axis angle constant deviation b m Estimated value of

[0012] S6: The entire satellite maneuvers a certain angle in a small range, and obtains the m-axis angle measurement scale coefficient k when it is L3 away from the target. m Estimated value of

[0013] S7, based on the estimated value of the m-axis third synthetic constant deviation in step S5 and m-axis angle measurement scale factor estimation Calculate the estimate of the non-co-basic position deviation of the m-axis

[0014] S8. Repeat steps S2 to S7 to complete the calibration of the angle constant deviation, angle measurement scale factor, and non-common base position deviation of all axes.

[0015] Preferably, the following definitions are made when constructing a non-co-basic parameter model for decoupling the x-axis and the y-axis:

[0016] Satellite coordinate system: The origin is located at the satellite's center of mass, the x-axis is perpendicular to the bottom plane of the satellite body and points to the top of the satellite body, the y-axis is parallel to the direction of satellite sail deployment; the z-axis constitutes a right-handed coordinate system;

[0017] Receiver coordinate system: O1 is the origin, located at the center of the signal receiver, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite coordinate system, and the z-axis forms a right-handed coordinate system;

[0018] Transmitter coordinate system: O2 is the origin, located at the center of the signal transmitter, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite body coordinate system, and the z-axis forms a right-handed coordinate system;

[0019] The distance between the target and the origin O1 of the receiving coordinate system is L, and the distance between the target center T and the origin O2 of the transmitting coordinate system is L′. Since the distance from O1 to O2 is much smaller than the distances from O1 and O2 to the target, it is approximately considered that L′=L.

[0020] Preferably, the m-axis angle measurement scale factor k m , m-axis angle measurement constant deviation b m , and the m-axis non-common reference position deviation K m The relationship equation is:

[0021]

[0022] α R is the target azimuth measured by the receiver, α j is the target azimuth in the transmitter coordinate system.

[0023] Preferably, the first synthetic constant deviation of the m-axis is defined as m-axis first synthetic constant deviation estimate The calculation method is:

[0024]

[0025] At this time, it is a steady-state aiming, and the measurement of the relative attitude deviation between the transmitter and the transmitter is basically 0, that is, α j ≈0; k m The nominal value of S1 is the first synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0026] Preferably, the second synthetic constant deviation of the m-axis is m-axis second synthetic constant deviation estimate The calculation method is:

[0027]

[0028] Where S2 is the second synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0029] Preferably, the third synthetic constant deviation θ of the m-axis 3,m The calculation method is: 3,m =k m K m ;

[0030] m-axis third composite constant deviation estimate for:

[0031]

[0032] Preferably, the m-axis angle constant deviation b m Estimated value of The calculation method is:

[0033]

[0034] Preferably, the m-axis angle measurement scale factor k m Estimated value of

[0035]

[0036] Where: S k Estimate the integral constant for the angle measurement scale factor, α j is the target azimuth in the transmitter coordinate system, α R is the target azimuth measured by the receiver, L3 is the distance between the receiver and the target after a small-range angle maneuver, and t is the measurement period.

[0037] Preferably, the m-axis non-co-base position deviation K is obtained m Estimated value The expression is:

[0038]

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] (1) The present invention provides an effective parameter calibration scheme to address the impact of non-common reference deviation on pointing accuracy. The established non-common reference parameter model containing three sets of parameters is suitable for applications where the transmitter and receiver are not in the same location and has good engineering practicality.

[0041] (2) The estimation method for non-common reference bias parameters relies only on a limited number of orbital maneuvers and attitude adjustments, and can obtain non-common reference parameter estimation results that are decoupled from distance, thereby improving the efficiency of non-common reference bias parameter estimation;

[0042] (3) The present invention can be widely applied to situations where the inter-satellite pointing of spacecraft is not based on a common reference, such as laser communication, space debris monitoring and other fields, and can provide a significant improvement in the pointing measurement accuracy in such scenarios. DETAILED DESCRIPTION

[0043] The purpose of the present invention is to solve the impact of non-common reference deviation on pointing accuracy and provide an effective parameter calibration scheme. By using the calibration results at two different distances, parameter estimation is obtained that is decoupled from the distance, thereby reducing the position constraints of the signal transmitter and the signal receiver.

[0044] In order to enable people skilled in the art to better understand the technical solution of this application, the technical solution of this application will be clearly and completely described below.

[0045] The specific steps of this method are as follows:

[0046] Step 1: Establish a non-co-basic parameter model. First, define the following coordinate system:

[0047] Satellite coordinate system: The origin is located at the satellite's center of mass, the x-axis is perpendicular to the bottom plane of the satellite body and points to the top of the satellite body, the y-axis is parallel to the direction of satellite sail deployment; the z-axis constitutes a right-handed coordinate system;

[0048] Receiver coordinate system: O1 is the origin, located at the center of the signal receiver, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite coordinate system, and the z-axis forms a right-handed coordinate system;

[0049] Transmitter coordinate system: O2 is the origin, located at the center of the signal transmitter, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite body coordinate system, and the z-axis constitutes a right-handed coordinate system.

[0050] The target vector can be expressed in the receiver coordinate system as:

[0051]

[0052] Where L is the distance between the target and the origin O1 of the receiver coordinate system, T is the center point of the target, Δx and Δy are the actual azimuth and elevation angles of the target in the receiver coordinate system, respectively. The target vector of the transmitter can be expressed in the transmitter coordinate system as:

[0053]

[0054] Where L′ is the distance between the target center T and the origin O2 of the transmitter coordinate system, α j and β j are the actual azimuth and elevation angles of the target in the transmitter coordinate system, respectively.

[0055] The relative position vector between the receiving end coordinate system and the transmitting end coordinate system is represented by:

[0056]

[0057] where K x Indicates the non-common reference position deviation in the x-axis direction, K y Indicates the non-common reference position deviation in the y-axis direction, K z Indicates the non-co-reference position deviation in the z-axis direction. Since the coordinate axes of the receiving end coordinate system and the transmitting end coordinate system are parallel, the vector synthesis method can be used to obtain:

[0058]

[0059] Considering the proportional deviation and constant deviation in the angle measurement of azimuth and elevation angles, equation (4) can be rewritten as:

[0060]

[0061] where α R =k x Δx+b x and β R =k y Δy+b y are the target azimuth and elevation angles measured at the receiving end, respectively, and k x 、k y is the angle measurement scale factor, b x 、b y is the constant deviation of angle measurement. The calibration coefficients required include the angle measurement scale factor (k x 、k y ), angle measurement constant deviation (b x 、b y ) and non-common reference position deviation (K x , K y )Three types of coefficients;

[0062] The values ​​that can be obtained by measurement include the target distance L measured by the receiver, the target azimuth α measured by the receiver R , β R , target azimuth angle α in the transmitter coordinate system j and pitch angle β j (This includes both transmitter-side target measurement and transmitter-side relative attitude deviation measurement.) Since the distance ΔL from O1 to O2 is much smaller than the distances from O1 and O2 to the target, we can approximately assume that L′ = L. L1, L2, and L3 below are the specific values ​​of the target distance L measured by the receiver (the distance between the receiver and the target).

[0063] At the same time, it can be seen from the formula that the x-axis and y-axis are decoupled from each other, so the x-axis and y-axis can be calibrated separately. The details are as follows:

[0064] S1. Use the vector synthesis method to construct a non-common basis parameter model for decoupling the x-axis and y-axis, and list equations to express the relationship between the three types of coefficients that need to be calibrated; use the m-axis to represent the x-axis or y-axis, that is, m∈{x,y}, and the coefficients that need to be calibrated for each axis are: angle measurement scale coefficient k m , Angle measurement constant deviation b m , and non-common reference position deviation K m ;in:

[0065] m-axis angle measurement scale factor k m , m-axis angle measurement constant deviation b m , and the m-axis non-common reference position deviation K m The relationship equation is:

[0066]

[0067] α R is the target azimuth measured by the receiver, α j is the target azimuth in the transmitter coordinate system.

[0068] S2. Measure the target at a distance of L1 and calculate the estimated value of the first synthetic constant deviation of the m-axis

[0069]

[0070] At this time, it is a steady-state aiming, and the measurement of the relative attitude deviation between the transmitter and the transmitter is basically 0, that is, α j ≈0; k m The nominal value of S1 is the first synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0071] S3. Measure the target at a distance of L2 and estimate the second synthetic constant deviation estimated value of the m-axis second synthetic constant deviation θ2.

[0072]

[0073] S2 is the second synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0074] S4. Utilization And the estimated value of the third synthetic constant deviation of the m-axis decoupled from the distance L1, L2 calculation

[0075]

[0076] S5. Utilization And the estimated value of the third synthetic constant deviation of the distance L1, L2 and m axis Calculate the m-axis angle constant deviation b m Estimated value of

[0077]

[0078] S6: The entire satellite maneuvers a certain angle in a small range, and obtains the m-axis angle measurement scale coefficient k when it is L3 away from the target. m Estimated value of

[0079]

[0080] S k Estimate the integral constant for the angle measurement scale factor, α j is the target azimuth in the transmitter coordinate system, α R is the target azimuth measured by the receiver, L3 is the distance between the receiver and the target after a small-range angle maneuver, and t is the measurement period.

[0081] S7, based on the m-axis third synthetic constant deviation estimated value in step S5 and m-axis angle measurement scale factor estimation Calculate the estimate of the non-co-basic position deviation of the m-axis

[0082] S8. Repeat steps S2 to S7 to complete the calibration of the angle constant deviation, angle measurement scale factor, and non-common base position deviation of all axes.

[0083] For the x-axis and y-axis respectively, the coefficients that need to be calibrated are: x-axis angle measurement scale coefficient kx , x-axis angle measurement constant deviation b x , and the x-axis non-common reference position deviation K x ; The coefficient that needs to be calibrated for the y-axis is: y-axis angle measurement proportional coefficient k y , y-axis angle measurement constant deviation b y , and the y-axis non-common reference position deviation K y .

[0084] 1. The x-axis is described independently below:

[0085] First, calibrate the x-axis coefficient. For the x-axis, the following equation holds:

[0086]

[0087] If k is x , K x and b x The three parameters are estimated simultaneously, cannot be decoupled, and are coupled with the target distance L, so it is impossible to ensure that each parameter converges to the true value. In particular Item, it is necessary to exclude the coupling of target distance L and k x and K x The coupling between them.

[0088] Step 2: For the target at distance L1, the target distance can be accurately obtained based on relative navigation measurement. Estimated value of Calculate, the specific calculation method is:

[0089]

[0090] Since it is a steady-state aiming at this time, the launch end measurement and the launch end star body relative attitude deviation measurement are basically 0, that is, α j ≈0. Therefore, k x Estimated value of Available nominal values Instead, the bias effect brought about by this is further weakened, S1 is the first synthetic constant bias estimation integral coefficient, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0091] Step 3: For the target at distance L2, the second synthetic constant deviation of the x-axis Estimated value of Calculate, the specific calculation method is:

[0092]

[0093] Where S2 is the second synthetic constant deviation estimation integral constant, αR is the target azimuth measured by the receiving end, and t is the measurement period.

[0094] Step 4: Based on the two estimation results, the third synthetic constant deviation θ of the x-axis is obtained 3,x =k x K x Estimated value of The calculation method is:

[0095]

[0096] Step 5: Based on the two estimation results, get b x The estimated results The calculation method is:

[0097]

[0098] Step 6: Maneuver the entire satellite in a small range to a certain angle to obtain the x-axis angle measurement scale factor k x Estimated value of The calculation method is:

[0099]

[0100] Where: S k Estimate the integral constant for the angle measurement scale factor, α j is the target azimuth in the transmitter coordinate system, α R is the target azimuth measured by the receiver, L3 is the distance between the receiver and the target during small-range angle maneuvers, and t is the measurement period.

[0101] Step 7: Get the x-axis non-co-base position deviation K x Estimated value The expression is:

[0102]

[0103] 2. Similarly, the y-axis coefficient can be calibrated through the above steps. Specifically:

[0104] For the y-axis, the following equation holds:

[0105]

[0106] If k is calculated by formula (13) y , K y and b y The three parameters are estimated simultaneously, cannot be decoupled, and are coupled with the target distance L, so it is impossible to ensure that each parameter converges to the true value. In particular Item, it is necessary to exclude the coupling of target distance L and k y and Ky The coupling between them.

[0107] Step 2: For the target at distance L1, the target distance can be accurately obtained based on relative navigation measurement. Estimated value of Calculate, the specific calculation method is:

[0108]

[0109] Since it is a steady-state aiming at this time, the launch end measurement and the launch end star body relative attitude deviation measurement are basically 0, that is, α j ≈0. Therefore, k y Estimated value of Available nominal values Instead, the bias effect brought about by this is further weakened, S1 is the first synthetic constant bias estimation integral coefficient, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0110] Step 3: For the target at distance L2, the second synthetic constant deviation of the y-axis Estimated value of Calculate, the specific calculation method is:

[0111]

[0112] Where S2 is the second synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

[0113] Step 4: Based on the two estimation results, get the third synthetic constant deviation θ of the y-axis 3,y =k y K y The estimated results The calculation method is:

[0114]

[0115] Step 5: Based on the two estimation results, get b y The estimated results The calculation method is:

[0116]

[0117] Step 6: Maneuver the entire satellite in a small range to a certain angle to obtain the y-axis angle measurement scale coefficient k y Estimated value of The calculation method is:

[0118]

[0119] Where: S k Estimate the integral constant for the angle measurement scale factor, α j is the target azimuth in the transmitter coordinate system, α R is the target azimuth measured by the receiver, L3 is the distance between the receiver and the target during small-range angle maneuvers, and t is the measurement period.

[0120] Step 7: Get the y-axis non-co-base position deviation K y Estimated value The expression is:

[0121]

[0122] The present invention considers the influence of measurement errors and installation deviations at the transmitting and receiving ends, establishes a non-co-basis parameter model for inter-satellite pointing containing three types of coefficients, and proposes a parameter estimation method that is decoupled from the target distance to address the problems of coupling between the target distance and angle measurement proportional coefficients and non-co-basis parameters.

[0123] Example:

[0124] A method for calibrating non-common reference parameters for intersatellite pointing of spacecraft includes establishing a non-common reference parameter model, L1 distance calibration, L2 distance calibration, angle constant deviation estimation, angle scale deviation estimation, and non-common reference position deviation estimation. This method includes the following steps:

[0125] (1) Using the vector synthesis method, a non-common-base parameter model for decoupling the x-axis and y-axis is constructed to obtain three types of coefficients that need to be calibrated: angle measurement scale coefficient (k x 、k y ), angle measurement constant deviation (b x 、b y ) and non-common reference position deviation (K x , K y ).

[0126] (2) For the x-axis coefficient (k x 、b x , K x ) is calibrated. First, the target at the L1 distance is measured and the first synthetic constant deviation estimate is calculated.

[0127] (3) Measure the target at the L2 distance and calculate the second synthetic constant deviation estimate

[0128] (4)Use And the distance measurement values ​​L1, L2 are calculated and decoupled from the third synthetic constant deviation estimate

[0129] (5) According to the third synthetic constant deviation estimate Calculate the angle constant deviation estimate

[0130] (6) The entire satellite maneuvers within a small range to a certain angle to obtain an estimate of the angle measurement scale coefficient

[0131] (7) Based on the synthetic deviation estimate in step (5) and angle measurement scale factor estimation Calculate the estimate of the non-co-basic position deviation

[0132] (8) Repeat steps (2) to (7) to calculate the angle constant deviation b of the y-axis. y , Angle measurement scale factor k y and the non-co-basic position deviation K y Carry out calibration.

[0133] Non-co-reference calibration involves measuring the target simultaneously at both the transmitter and receiver to calibrate and correct the systematic deviations between the transmitter and receiver, thereby improving pointing accuracy in non-co-reference configurations. This method calibrates these parameters by observing the same target twice at different distances.

[0134] The simulation sets the nominal value of the angle constant deviation to 0.5", the nominal value of the angle scale factor to 1.01, and the nominal value of the non-co-reference position deviation to 2.5m. The initial values ​​of the three parameters are nominal values. The true values ​​are 0.82", 1.02, and 2.55m, respectively. Based on the proposed non-co-reference calibration simulation, the parameter estimation decoupled from the distance is obtained. The estimated result of the angle constant deviation is 0.8458" with an accuracy of 0.0258"; the estimated result of the angle scale factor is 1.0201 with an accuracy of 0.0001; and the calibration result of the non-co-reference position deviation is 2.5526m with an accuracy of 0.0026m.

[0135] The contents not described in detail in the specification of the present invention belong to the prior art known to those skilled in the art.

Claims

1. A method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft, characterized in that include: S1. Use the vector synthesis method to construct a non-common basis parameter model for decoupling the x-axis and y-axis, and list equations to express the relationship between the three types of coefficients that need to be calibrated; use the m-axis to represent the x-axis or y-axis, that is, m∈{x,y}. The coefficients that need to be calibrated for each axis are: angle measurement scale coefficient k m , Angle measurement constant deviation b m , and non-common reference position deviation K m ; S2. Measure the target at a distance of L1 and calculate the first synthetic constant deviation θ of the m-axis 1,m Estimated value of S3. Measure the target at a distance of L2 and calculate the second synthetic constant deviation θ of the m-axis 2,m Estimated value of S4. Utilization As well as the distances L1 and L2, calculate the third synthetic constant deviation θ of the m-axis decoupled from the distance 3,m Estimated value of S5. Utilization Estimated values ​​of the third composite constant deviation of the distance L1, L2 and m axis Calculate the m-axis angle constant deviation b m Estimated value of S6: The entire satellite maneuvers a certain angle in a small range, and obtains the m-axis angle measurement scale coefficient k when it is L3 away from the target. m Estimated value of S7, based on the estimated value of the m-axis third synthetic constant deviation in step S5 and m-axis angle measurement scale factor estimation Calculate the estimate of the non-co-basic position deviation of the m-axis S8. Repeat steps S2 to S7 to complete the calibration of the angle constant deviation, angle measurement scale factor, and non-common base position deviation of all axes.

2. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 1, characterized in that: The following definitions are made when constructing a non-co-basic parameter model for decoupling the x-axis and y-axis: Satellite coordinate system: The origin is located at the satellite's center of mass, the x-axis is perpendicular to the bottom plane of the satellite body and points to the top of the satellite body, the y-axis is parallel to the direction of satellite sail deployment; the z-axis constitutes a right-handed coordinate system; Receiver coordinate system: O1 is the origin, located at the center of the signal receiver, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite coordinate system, and the z-axis forms a right-handed coordinate system; Transmitter coordinate system: O2 is the origin, located at the center of the signal transmitter, the x-axis and y-axis are parallel to the x-axis and y-axis of the satellite body coordinate system, and the z-axis forms a right-handed coordinate system; The distance between the target and the origin O1 of the receiving coordinate system is L, and the distance between the target center T and the origin O2 of the transmitting coordinate system is L′. Since the distance from O1 to O2 is much smaller than the distances from O1 and O2 to the target, it is approximately considered that L′=L.

3. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 2, characterized in that: m-axis angle measurement scale factor k m , m-axis angle measurement constant deviation b m , and the m-axis non-common reference position deviation K m The relationship equation is: α R is the target azimuth measured by the receiver, α j is the target azimuth in the transmitter coordinate system.

4. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 3, characterized in that: Define the first synthetic constant deviation of the m-axis as Estimated value of the first synthetic constant deviation of the m-axis for: At this time, it is a steady-state aiming, and the measurement of the relative attitude deviation between the transmitter and the transmitter is basically 0, that is, α j ≈0; k m The nominal value of S1 is the first synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

5. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 4, characterized in that: The second synthetic constant deviation of the m-axis is Estimated value of the second composite constant deviation of the m-axis for: Where S2 is the second synthetic constant deviation estimation integral constant, α R is the target azimuth measured by the receiving end, and t is the measurement period.

6. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 5, characterized in that: The third synthetic constant deviation θ of the m-axis 3,m is: θ 3,m =k m K m ; Estimated value of the third composite constant deviation of the m-axis for:

7. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 6, characterized in that: m-axis angle constant deviation b m Estimated value of for:

8. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 7, characterized in that: m-axis angle measurement scale factor k m Estimated value of for: Where: S k Estimate the integral constant for the angle measurement scale factor, α j is the target azimuth in the transmitter coordinate system, α R is the target azimuth measured by the receiver, L3 is the distance between the receiver and the target after a small-range angle maneuver, and t is the measurement period.

9. The method for calibrating non-common reference parameters of inter-satellite pointing of spacecraft according to claim 8, characterized in that: Get the m-axis non-co-base position deviation K m Estimated value The expression is:

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