Inter-satellite link-based satellite clock bias determination method, apparatus, and electronic equipment

Abstract

This invention discloses a method, apparatus, and electronic equipment for determining satellite clock bias based on inter-satellite links, relating to the field of aerospace telemetry and control. The method includes: acquiring inter-satellite link measurement data; preprocessing the data to obtain inter-satellite link data; segmenting the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval; calculating the observation residuals at each observation time within each segment interval based on the inter-satellite link data of the segment intervals and the theoretical inter-satellite distance; calculating the clock bias coefficient vector within each segment interval using the statistical weighted least squares method based on the observation residuals at each observation time within the segment intervals; and determining the satellite clock bias of the first observation satellite and the second observation satellite within each segment interval based on the clock bias coefficient vectors of the segment intervals. This invention solves the technical problem of low accuracy in related satellite clock bias estimation techniques under complex Earth-Moon space backgrounds.

Description

Technical Field

[0001] This invention relates to the field of aerospace telemetry and control or other related technical fields. Specifically, it relates to a method, apparatus, and electronic equipment for determining satellite clock bias based on inter-satellite links. Background Technology

[0002] Inter-satellite link technology plays a crucial role in communication and navigation systems in the Earth-Moon space. It not only enhances the system's robustness and coverage but also provides spacecraft with precise relative positioning information. Inter-satellite links offer a direct and efficient means of data transmission and navigation between spacecraft by measuring the distance or time delay between satellites. However, the measurement data from inter-satellite links is affected by various factors, with satellite clock bias being one of the main reasons for the decrease in absolute accuracy of one-way inter-satellite measurements.

[0003] Satellite clock bias refers to the deviation between a clock carried by a satellite and standard time on Earth (such as International Atomic Time, TAI). This deviation can be caused by a variety of factors, including clock instability, environmental temperature differences, electromagnetic interference, gravitational field variations, and relativistic effects. While satellite clock bias processing is relatively mature in Earth-space communication and navigation systems, it faces new challenges in the Earth-Moon space environment due to longer signal travel times, a more complex gravitational environment, and more significant relativistic effects.

[0004] In Earth-Moon space communication and navigation systems, the distance between satellites can reach hundreds of thousands of kilometers. This means that signal propagation time is significantly increased, and even small changes in satellite clock bias are amplified, thus having a significant impact on inter-satellite link measurement results. Furthermore, satellites operate within the gravity gradients of the Earth and the Moon, experiencing a more diverse space environment, leading to more complex trends in satellite clock bias. Current technologies for estimating satellite clock bias largely rely on two-way ranging from ground stations, autonomous calibration of onboard atomic clocks, or indirect estimation using inter-satellite link data. However, these methods have certain limitations in the Earth-Moon space environment:

[0005] Two-way ranging based on ground stations is limited by the influence of the Earth's atmosphere and the measurement range, and may not be able to provide continuous and globally covered clock error estimates.

[0006] The autonomous calibration of spaceborne atomic clocks requires periodic uploading of calibration parameters from ground stations, and errors may accumulate after long-term operation.

[0007] Indirect estimation methods using inter-satellite link data may lack sufficient accuracy when dealing with complex space environment influences and high-precision requirements.

[0008] There is currently no effective solution to the above problems. Summary of the Invention

[0009] This invention provides a method, apparatus, and electronic device for determining satellite clock bias based on inter-satellite links, in order to at least solve the technical problem of low accuracy of related satellite clock bias estimation techniques in the complex background environment of Earth-Moon space.

[0010] According to one aspect of the present invention, a method for determining satellite clock bias based on inter-satellite links is provided, comprising: acquiring inter-satellite link measurement data; preprocessing the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and the observation inter-satellite distance between a first observation satellite and a second observation satellite at each observation time; segmenting the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval, wherein N is a positive integer; calculating the observation residual for each observation time within the segment interval based on the inter-satellite link data of the segment interval and the theoretical inter-satellite distance; calculating the clock bias coefficient vector within the segment interval using statistical weighted least squares method based on the observation residual for each observation time within the segment interval; and determining the satellite clock bias of the first observation satellite and the satellite clock bias of the second observation satellite within each segment interval based on the clock bias coefficient vector of the segment interval.

[0011] Optionally, the step of segmenting the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval includes: obtaining the observation duration of the entire observation process corresponding to the inter-satellite link data; determining the segment period based on the stability of the onboard clock; and dividing the inter-satellite link data based on the observation duration and the segment period to obtain N segment intervals and inter-satellite link data for each segment interval.

[0012] Optionally, after segmenting the inter-satellite link data, the method further includes: establishing a higher-order polynomial corresponding to the satellite clock difference for each segment interval, wherein the higher-order polynomial is expressed as: Where a(t) is the satellite clock error of the segmented interval, m represents the m-th segmented interval, and i represents the order. Let represent the coefficients of the i-th order polynomial of the satellite clock error within the m-th segment interval, and n represent the highest order of the polynomial.

[0013] Optionally, the step of calculating the observation residuals for each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distances includes: extracting the observation inter-satellite distances for each observation time from the inter-satellite link data of the segmented interval; transmitting a signal from the first observation satellite to the second observation satellite at each observation time; calculating the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite; calculating the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite; calculating the theoretical inter-satellite distances for each observation time based on the first position vectors and the second position vectors; and calculating the difference between the observation inter-satellite distances and the theoretical inter-satellite distances at each observation time to obtain the observation residuals for each observation time within the segmented interval.

[0014] Optionally, the step of calculating the clock error coefficient vector within the segmented interval using the statistical weighted least squares method based on the observation residuals at each observation time includes: establishing observation equations for each observation time based on the observation residuals at each observation time, wherein the observation equations are expressed as: To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. The clock error coefficient vector of the second observation satellite is represented by the clock error coefficient vector of the segmented interval by fitting the observation equation at each observation time using the statistical weighted least squares method.

[0015] Optionally, the step of determining the satellite clock error of the first observation satellite and the satellite clock error of the second observation satellite in each segmented interval based on the clock error coefficient vector of the segmented interval includes: extracting a first clock error coefficient set of the first observation satellite from the clock error coefficient vector of the segmented interval; substituting the first clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval; extracting a second clock error coefficient set of the second observation satellite from the clock error coefficient vector of the segmented interval; substituting the second clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the second observation satellite in the segmented interval.

[0016] Optionally, the preprocessing step for the inter-satellite link measurement data includes: detecting outliers in the inter-satellite link measurement data and removing the detected outliers; and smoothing the inter-satellite link measurement data to remove noise from the data.

[0017] According to another aspect of the present invention, a satellite clock bias determination device based on inter-satellite links is also provided, comprising: an acquisition unit, configured to acquire inter-satellite link measurement data, preprocess the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and observation inter-satellite distance between a first observation satellite and a second observation satellite at each observation time; a segmentation unit, configured to segment the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval, wherein N is a positive integer; a first calculation unit, configured to calculate the observation residuals at each observation time within the segment intervals based on the inter-satellite link data of the segment intervals and the theoretical inter-satellite distances; a second calculation unit, configured to calculate the clock bias coefficient vector within the segment intervals using statistical weighted least squares method based on the observation residuals at each observation time within the segment intervals; and a determination unit, configured to determine the satellite clock bias of the first observation satellite in each segment interval and the satellite clock bias of the second observation satellite in each segment interval based on the clock bias coefficient vector of the segment intervals.

[0018] Optionally, the segmentation unit includes: a first acquisition module, used to acquire the observation duration of the entire observation process corresponding to the inter-satellite link data; a first determination module, used to determine the segmentation period based on the stability of the onboard clock; and a first division module, used to divide the inter-satellite link data based on the observation duration and the segmentation period to obtain N segment intervals and the inter-satellite link data in each segment interval.

[0019] Optionally, the satellite clock bias determination device based on inter-satellite links further includes: a first establishment module, used to establish a higher-order polynomial corresponding to the satellite clock bias of each segmented interval, wherein the higher-order polynomial is expressed as: Where a(t) is the satellite clock error of the segmented interval, m represents the m-th segmented interval, and i represents the order. Let represent the coefficients of the i-th order polynomial of the satellite clock error within the m-th segment interval, and n represent the highest order of the polynomial.

[0020] Optionally, the first calculation unit includes: a first extraction module, used to extract the observed inter-satellite distance at each observation time from the inter-satellite link data of the segmented interval; a first calculation module, used to transmit a signal from the first observation satellite to the second observation satellite at each observation time, calculate the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite, and calculate the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite; a second calculation module, used to calculate the theoretical inter-satellite distance at each observation time based on the first position vector and the second position vector; and a third calculation module, used to calculate the difference between the observed inter-satellite distance at each observation time and the theoretical inter-satellite distance, to obtain the observation residual at each observation time within the segmented interval.

[0021] Optionally, the second calculation unit includes: a second establishment module, configured to establish an observation equation for each observation time based on the observation residuals at each observation time, wherein the observation equation is expressed as: To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. The clock error coefficient vector of the second observation satellite is represented; the first fitting module is used to fit the observation equation at each observation time using the statistical weighted least squares method to obtain the clock error coefficient vector of the segmented interval.

[0022] Optionally, the determining unit includes: a second extraction module, used to extract a first set of clock error coefficients for the first observation satellite from the clock error coefficient vector of the segmented interval; a fourth calculation module, used to substitute the first set of clock error coefficients into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval; a third extraction module, used to extract a second set of clock error coefficients for the second observation satellite from the clock error coefficient vector of the segmented interval; and a fifth calculation module, used to substitute the second set of clock error coefficients into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the second observation satellite in the segmented interval.

[0023] Optionally, the satellite clock bias determination device based on inter-satellite links further includes: a first detection module, used to detect outliers in the inter-satellite link measurement data and remove the detected outliers; and a first processing module, used to smooth the inter-satellite link measurement data and remove noise from the data.

[0024] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is executed, it controls the device where the computer-readable storage medium is located to execute any of the above-described inter-satellite link-based satellite clock bias determination methods.

[0025] According to another aspect of the present invention, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement any of the above-described methods for determining satellite clock bias based on inter-satellite links.

[0026] In this application, the following steps are taken: First, inter-satellite link measurement data is acquired. The inter-satellite link measurement data is preprocessed to obtain inter-satellite link data. The inter-satellite link data includes at least: observation time, the observation inter-satellite distance between the first and second observation satellites at each observation time, and the inter-satellite link data is segmented to obtain N segment intervals and inter-satellite link data for each segment interval, where N is a positive integer. Then, based on the inter-satellite link data of the segment intervals and the theoretical inter-satellite distance, the observation residuals at each observation time within the segment intervals are calculated. Based on the observation residuals at each observation time within the segment intervals, the clock error coefficient vector within the segment intervals is calculated using the statistical weighted least squares method. Finally, based on the clock error coefficient vectors of the segment intervals, the satellite clock error of the first observation satellite in each segment interval and the satellite clock error of the second observation satellite in each segment interval are determined.

[0027] In this application, the nonlinear variation trend of the satellite clock is characterized by a higher-order polynomial, and the coefficients of the higher-order polynomial, i.e., the clock error coefficients, are fitted using the statistical weighted least squares method of the observation data. The clock error coefficients are then substituted into the higher-order polynomial to solve for the satellite clock error in each observation interval. The satellite clock error is represented by a piecewise higher-order method, which allows for a more accurate description of the satellite clock error in each segment, thus achieving the goal of accurately calculating the satellite clock error. This improves the accuracy of the satellite clock error calculation results and solves the technical problem of low accuracy of related satellite clock error estimation techniques in the complex background environment of the Earth-Moon space. Attached Figure Description

[0028] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0029] Figure 1 This is a flowchart of an optional inter-satellite link-based satellite clock bias determination method according to an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of an optional segmentation of satellite clock bias according to an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of an optional inter-satellite link-based satellite clock bias determination device according to an embodiment of the present invention;

[0032] Figure 4 This is a hardware structure block diagram of an electronic device (or mobile device) that performs a satellite clock bias determination method based on inter-satellite links according to an embodiment of the present invention. Detailed Implementation

[0033] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0035] It should be noted that the satellite clock bias determination method and apparatus based on inter-satellite links in this application can be used in the aerospace telemetry and control field when determining the satellite clock bias at each moment based on piecewise high-order polynomials, and can also be used in any field other than aerospace telemetry and control when determining the satellite clock bias at each moment based on piecewise high-order polynomials. This application does not limit the application field of the satellite clock bias determination method and apparatus based on inter-satellite links.

[0036] It should be noted that the relevant information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, and displayed data) involved in this application are information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of this data all comply with the relevant laws, regulations, and standards of the relevant regions, have taken necessary confidentiality measures, do not violate public order and good morals, and provide corresponding access points for users to choose to authorize or refuse. For example, this system has an interface with relevant users or organizations. Before obtaining relevant information, a request to obtain the information needs to be sent to the aforementioned user or organization through the interface, and the relevant information is obtained only after receiving consent from the aforementioned user or organization.

[0037] It should be noted that in this application, when collecting and analyzing customer information, users are provided with corresponding operation entry points to choose whether to agree to or reject the automated decision-making results; if the user chooses to reject, the process will proceed to the expert decision-making process.

[0038] The following embodiments of the present invention can be applied to satellite clock bias determination systems / applications / devices based on inter-satellite links. The present invention proposes a satellite clock bias estimation method based on inter-satellite links, which can characterize the changes in satellite clock bias in the Earth-Moon space using high-order polynomials, and calculate the satellite clock bias through satellite combinations in the inter-satellite link, thereby achieving high-precision correction of inter-satellite link ranging data and providing high-precision data support for orbit determination calculations of Earth-Moon spacecraft.

[0039] The present invention will now be described in detail with reference to various embodiments.

[0040] Example 1

[0041] According to an embodiment of the present invention, an embodiment of a satellite clock bias determination method based on inter-satellite links is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0042] Figure 1 This is a flowchart of an optional inter-satellite link-based satellite clock bias determination method according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0043] Step S101: Obtain inter-satellite link measurement data, preprocess the inter-satellite link measurement data to obtain inter-satellite link data.

[0044] In step S101 above, the inter-satellite link can be a wireless communication link established between any two or more satellites, especially for inter-satellite links within the Earth-Moon space region or applicable to the Earth-Moon space environment. The telemetry and control signals of the inter-satellite link can obtain the relative distance between satellites for use in satellite orbit calculation. The essence of inter-satellite link measurement is the time delay of signal transmission between two satellites, which includes both the inter-satellite geometric distance and the clock errors of the two satellites. Due to the physical properties of the onboard clock itself and the space environment, the error of the onboard clock is difficult to model accurately, directly manifesting as a systematic deviation in inter-satellite ranging. Earth-Moon space inter-satellite links differ from those in Earth space. Their main significant characteristics include a longer optical travel time for signals in Earth-Moon space and a more complex space gravitational environment, leading to more significant satellite clock errors caused by relativistic effects.

[0045] In this embodiment of the invention, the inter-satellite link data includes at least: the observation time and the observation distance between the first and second observation satellites at each observation time.

[0046] This invention calculates the satellite clock difference between two satellites from the perspective of satellite clock difference by using inter-satellite link data, thereby providing more accurate measurement data for aerial exploration and providing high-precision time synchronization services and positioning data for the Earth-Moon space communication and navigation system.

[0047] Optionally, the preprocessing steps for inter-satellite link measurement data include: detecting outliers in the inter-satellite link measurement data and removing the detected outliers; and smoothing the inter-satellite link measurement data to remove noise from the data.

[0048] It should be noted that when using inter-satellite links to observe targets, the acquired data is inter-satellite link measurement data at any given time, resulting in a large data volume. After acquiring the inter-satellite link measurement data, preprocessing is required. This includes: using various statistical or machine learning methods to detect outliers, identifying and removing observations that significantly deviate from the normal range based on data distribution or model predictions. Preprocessing also includes smoothing the inter-satellite link measurement data to remove noise. Preprocessing ensures data accuracy, enhances data stability, and improves the accuracy of satellite clock bias estimation and calculation.

[0049] In another optional embodiment, the step of preprocessing the inter-satellite link measurement data further includes: obtaining the observation timestamp of each inter-satellite link measurement data, sorting the inter-satellite link measurement data according to the observation timestamps to obtain time-series inter-satellite link data, which serves as the data basis for subsequent segmentation.

[0050] Step S102: Segment the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval, where N is a positive integer.

[0051] In step S102 above, the inter-satellite link data (i.e. the time-series inter-satellite link data) is divided into multiple segment intervals by segmentation. Since the performance of satellite clocks and environmental conditions vary greatly, dividing the inter-satellite link data allows the performance of satellite clocks and environmental conditions to remain relatively stable within each short segment interval, thereby enabling more accurate modeling of the changing trend of satellite clock bias.

[0052] In this embodiment, in the application scenario of the Earth-Moon space communication and navigation system, the stability of satellite clocks may be affected by the complex space environment and long-term operation, exhibiting a nonlinear trend. Piecewise high-order polynomials can more accurately describe this complex clock bias variation, and based on the aforementioned piecewise data, the uncertainty accumulated during long-term observation can be reduced, improving the reliability of clock bias estimation.

[0053] Optionally, the steps of segmenting the inter-satellite link data to obtain N segment intervals and the inter-satellite link data for each segment interval include: obtaining the observation duration of the entire observation process corresponding to the inter-satellite link data; determining the segment period based on the stability of the onboard clock; and dividing the inter-satellite link data based on the observation duration and the segment period to obtain N segment intervals and the inter-satellite link data for each segment interval.

[0054] Specifically, firstly, the observation duration of the entire inter-satellite link data observation process is determined by recording the time difference between the first and last observations. Secondly, based on the stability indicators of the satellite clock and the characteristics of the inter-satellite link data, a reasonable segment time length, i.e., the segment period, is determined. This time length should be sufficient to capture significant changes in satellite clock bias, but not so long that the clock bias changes become overly complex and difficult to model accurately. Then, based on the acquired observation duration and the determined segment period, the total number N of possible segment intervals is calculated, and the observation time window is equally divided into N consecutive intervals according to the segment period. The entire observation time window is uniformly divided to obtain N segment intervals, where N is a positive integer selected based on specific observation requirements and data characteristics.

[0055] For example, when dividing the inter-satellite link data, all inter-satellite link data are sorted in chronological order to determine the time interval [t] containing all inter-satellite link observations. beg ,t end ] Calculate the time length of the observation interval (corresponding to the observation duration mentioned above) t dur =t beg -t endThe time length (corresponding to the aforementioned segment period) T, representing the clock bias segment, is determined based on the stability of the satellite's onboard clock. Combined with the time length of the observation interval, the number of segments for the satellite clock bias is determined. [] indicates rounding up.

[0056] By taking the above steps and rationally selecting the segmentation period and the number of segmentation intervals, the efficiency of inter-satellite link data processing and the accuracy of satellite clock error estimation are significantly improved.

[0057] Optionally, after segmenting the inter-satellite link data, the method further includes: establishing a higher-order polynomial corresponding to the satellite clock bias for each segment interval, wherein the higher-order polynomial is expressed as: Where a(t) is the satellite clock error of the segmented interval, m represents the m-th segmented interval, and i represents the order. Let represent the coefficients of the i-th order polynomial of the satellite clock error within the m-th segment interval, and n represent the highest order of the polynomial.

[0058] In some embodiments, segmenting inter-satellite link data aims to construct higher-order polynomials within each segment interval. This segmented higher-order polynomial is then used to fit satellite clock bias, allowing for a more accurate modeling of the trend in satellite clock bias variation, especially when satellite clock performance changes significantly over time. Specifically, a higher-order polynomial corresponding to the satellite clock bias is established within each segment interval. This higher-order polynomial contains polynomial coefficients of various orders, i.e., clock bias coefficients. Then, the set of polynomial coefficients within each segment interval is fitted based on the inter-satellite measurement data. By substituting the polynomial coefficients of each order into the higher-order polynomial, the satellite clock bias can be solved.

[0059] For example, the satellite clock bias of each segmented interval is represented by a higher-order polynomial, which can be expressed as:

[0060]

[0061] In the formula, The coefficients of the higher-order polynomial within the segmented interval are represented by m = 0, 1, ..., N-1, which represents the starting point of the segmented interval, and n represents the highest order of the polynomial.

[0062] Step S103: Calculate the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distances of the segmented intervals.

[0063] Figure 2 This is a schematic diagram of an optional segmentation of satellite clock bias according to an embodiment of the present invention, such as... Figure 2 As shown, the observation process corresponding to the inter-satellite link data is divided into N segmented intervals, i.e. Figure 2 In the [t0,t1], [t1,t2], [t2,t3], ..., [tN-2 ,t N-1 ],[t N-1 ,t N Each segmented interval corresponds to a higher-order polynomial of the satellite clock bias, such as... Figure 2 In the equation, the piecewise higher-order polynomial corresponding to [t0,t1] is: The piecewise higher-order polynomial corresponding to [t1,t2] is: The piecewise higher-order polynomial corresponding to [t2,t3] is: [t N-2 ,t N-1 The corresponding piecewise higher-order polynomial is: [t N-1 ,t N The corresponding piecewise higher-order polynomial is:

[0064] In step S103 above, the influence of satellite clock bias on inter-satellite link distance measurement is extracted by subtracting the inter-satellite link data from the theoretical inter-satellite distance (i.e., the observation residual), providing a solid data foundation for high-precision estimation of satellite clock bias. The calculation of the observation residual not only reveals systematic biases in inter-satellite link measurements but also helps identify performance problems with satellite clocks and environmental interference factors, providing crucial information for data correction and system optimization.

[0065] Optionally, the step of calculating the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distances within the segmented interval includes: extracting the observed inter-satellite distances at each observation time from the inter-satellite link data of the segmented interval; transmitting a signal from the first observation satellite to the second observation satellite at each observation time, calculating the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite, and calculating the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite; calculating the theoretical inter-satellite distances at each observation time based on the first and second position vectors; and calculating the difference between the observed inter-satellite distances at each observation time and the theoretical inter-satellite distances to obtain the observation residuals at each observation time within the segmented interval.

[0066] Specifically, when calculating the observation residual, the observed inter-satellite distance value at each moment is first extracted from the inter-satellite link data to obtain the observed inter-satellite distance, which is then compared with the theoretical inter-satellite distance value at the corresponding moment. The difference between the two is calculated, which is the observation residual. This difference reflects the influence of satellite clock errors on the observed distance.

[0067] For example, marking inter-satellite link measurements The inter-satellite distance is measured and transmitted from satellite A (e.g., the first observation satellite) and received by satellite B (e.g., the second observation satellite). The inter-satellite link measurement data at time t is calculated. The corresponding theoretical interstellar distance In the formula, This represents the position vector of satellite A at the moment of signal transmission (corresponding to the first position vector mentioned above). This represents the position vector of satellite B at the moment of signal reception (corresponding to the second position vector mentioned above). Then, the inter-satellite link measurement... It can be represented as:

[0068] Inter-satellite link measurements include the clock bias between satellites A and B, and their expression is:

[0069]

[0070] Where c1 represents the clock error coefficient of satellite A, and c2 represents the clock error coefficient of satellite B. The observation residual of the inter-satellite link is defined as...

[0071] Step S104: Based on the observation residuals at each observation time within the segmented interval, calculate the clock error coefficient vector within the segmented interval using the statistical weighted least squares method.

[0072] In step S104 above, a design matrix (corresponding to the above observation equation) is constructed based on the observation residuals at each observation time within the segmented interval, and the clock error coefficient vector within the segmented interval is calculated using the statistical weighted least squares method. The method of estimating clock error coefficients using the statistical weighted least squares method provides high-precision satellite clock error modeling parameters, which is crucial for achieving inter-satellite link data calibration and improving the accuracy of spacecraft orbit calculations.

[0073] Optionally, the step of calculating the clock error coefficient vector within the segmented interval using the statistical weighted least squares method based on the observation residuals at each observation time includes: establishing the observation equation for each observation time based on the observation residuals at each observation time, wherein the observation equation is expressed as: To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. This represents the clock error coefficient vector of the second observation satellite; the observation equations at each observation time are fitted and calculated using the statistical weighted least squares method to obtain the clock error coefficient vector for the segmented intervals.

[0074] Specifically, based on the observation residuals calculated in the preceding steps, for each segmented interval, a list or matrix containing the observation residuals for all observation times is prepared. A design matrix is ​​then constructed based on the order and form of the piecewise high-order polynomial model. Each row of this matrix corresponds to an observation time and contains the coefficients of the polynomial terms corresponding to that time, thus reflecting the linear relationship between the observation residuals and the clock error coefficients. Then, by solving the statistical weighted least squares problem, i.e., minimizing the sum of squares of the observation residuals, the clock error coefficient vector is obtained.

[0075] In another alternative embodiment, a weight matrix W is constructed based on the statistical properties of the observed residuals (such as variance or standard deviation). Each item W in the weight matrix... i This reflects the reliability of the data at the corresponding observation time and is usually inversely proportional to the variance of the observation residuals. This strategy ensures that high-quality data plays a greater role in clock error estimation, while the impact of low-quality data on the results is appropriately mitigated.

[0076] For example, calculate the partial derivatives of the inter-satellite link measurements with respect to the clock biases of satellites A and B. Calculate the partial derivative of the clock error coefficient of satellite A (corresponding to the first observation satellite mentioned above) with respect to any time t.

[0077]

[0078] The above This represents the clock error coefficient of the first observation satellite.

[0079] Calculate the partial derivative of the clock error coefficient of satellite B (corresponding to the second observation satellite mentioned above) with respect to any time t.

[0080]

[0081] The above This represents the clock error coefficient of the second observation satellite.

[0082] Each set of observation data, that is, the data within each segment interval, can be used to construct the following equation (corresponding to the observation equation above).

[0083]

[0084] In the formula, This represents the clock error coefficient vector of satellite A in each segmented interval. This represents the clock error coefficient vector of star B in each segment interval.

[0085] Specifically, this can be expanded as follows:

[0086]

[0087] mark Therefore, for a set of observation data, the above can be rewritten as follows:

[0088]

[0089] For k sets of observation data, it can be written as:

[0090]

[0091] Label O = [o1, o2, ..., o k ] T H = [h1, h2, ..., h l ] T Then the solution to the above equation can be expressed as:

[0092]

[0093] Therefore, the clock error coefficient vector can be obtained, which contains the clock error coefficients of the first and second observation satellites at various times in the segmented intervals.

[0094] Step S105: Determine the satellite clock difference of the first observation satellite in each segmented interval and the satellite clock difference of the second observation satellite in each segmented interval based on the clock difference coefficient vector of the segmented interval.

[0095] In step S105 above, the clock error coefficients of the first and second observation satellites are extracted based on the obtained clock error coefficient vector, and combined with the pre-established high-order polynomial to solve the satellite clock error of the observation satellite in the segmented interval. This embodiment of the invention achieves a fine estimate of satellite clock error by taking advantage of the flexibility of the high-order polynomial model and the accuracy of the statistical weighted least squares method.

[0096] Optionally, the steps of determining the satellite clock error of the first observation satellite and the satellite clock error of the second observation satellite in each segmented interval based on the clock error coefficient vector of the segmented interval include: extracting the first clock error coefficient set of the first observation satellite from the clock error coefficient vector of the segmented interval; substituting the first clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval; extracting the second clock error coefficient set of the second observation satellite from the clock error coefficient vector of the segmented interval; substituting the second clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the second observation satellite in the segmented interval.

[0097] Specifically, the clock bias coefficient vector is calculated using statistical weighted least squares and contains descriptions of the clock bias changes of the first and second observation satellites across multiple segmented intervals. Therefore, the first step is to identify which coefficients correspond to the clock bias changes of the first observation satellite within the current segmented interval. These coefficients are then extracted to form the first clock bias coefficient set. This first clock bias coefficient set is substituted into the high-order polynomial model corresponding to the segmented interval of the first observation satellite for mathematical operations to obtain the satellite clock bias of the first observation satellite within the segmented interval. Similarly, the set of coefficients related to the clock bias changes of the second observation satellite is selected from the clock bias coefficient vector. This second clock bias coefficient set is then substituted into the high-order polynomial model corresponding to the second observation satellite to calculate the satellite clock bias of the second observation satellite within the segmented interval.

[0098] Through the above steps, firstly, inter-satellite link measurement data is acquired. This data is then preprocessed to obtain inter-satellite link data, which includes at least: the observation time, the observed inter-satellite distance between the first and second observation satellites at each observation time, and the inter-satellite link data is segmented into N segment intervals, with N being a positive integer. Then, based on the inter-satellite link data and theoretical inter-satellite distances within each segment interval, the observation residuals at each observation time are calculated. Based on these residuals, the clock bias coefficient vector within each segment interval is calculated using statistical weighted least squares. Finally, based on the clock bias coefficient vectors, the satellite clock bias of the first observation satellite and the second observation satellite within each segment interval are determined.

[0099] In this embodiment, the nonlinear variation trend of the onboard clock is characterized by a higher-order polynomial, and the coefficients of the higher-order polynomial, i.e., the clock error coefficients, are fitted using the statistical weighted least squares method of the observation data. The clock error coefficients are then substituted into the higher-order polynomial to solve for the satellite clock error in each observation interval. The satellite clock error adopts a piecewise higher-order representation method, which allows for a more accurate description of the satellite clock error in each segment, thus achieving the goal of accurately calculating the satellite clock error. This achieves the technical effect of improving the accuracy of the satellite clock error calculation results, thereby solving the technical problem of low accuracy of related satellite clock error estimation technology in the complex background environment of Earth-Moon space.

[0100] The following is a detailed description with reference to another embodiment.

[0101] Example 2

[0102] The satellite clock bias determination device based on inter-satellite links provided in this embodiment includes multiple implementation units, each of which corresponds to a specific implementation step in the above embodiment one. The specific implementation method and beneficial effects can be referred to the aforementioned method embodiment, and will not be repeated here.

[0103] Figure 3 This is a schematic diagram of an optional inter-satellite link-based satellite clock bias determination device according to an embodiment of the present invention, such as... Figure 3 As shown, the satellite clock bias determination device based on inter-satellite links includes: an acquisition unit 31, a segmentation unit 32, a first calculation unit 33, a second calculation unit 34, and a determination unit 35, wherein,

[0104] The acquisition unit 31 is used to acquire inter-satellite link measurement data, preprocess the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: the observation time and the observation inter-satellite distance between the first observation satellite and the second observation satellite at each observation time;

[0105] Segmentation unit 32 is used to segment the inter-satellite link data to obtain N segmented intervals and inter-satellite link data for each segmented interval, where N is a positive integer;

[0106] The first calculation unit 33 is used to calculate the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distance of the segmented interval;

[0107] The second calculation unit 34 is used to calculate the clock error coefficient vector in the segmented interval based on the observation residuals at each observation time in the segmented interval using the statistical weighted least squares method.

[0108] The determination unit 35 is used to determine the satellite clock difference of the first observation satellite in each segment interval and the satellite clock difference of the second observation satellite in each segment interval based on the clock difference coefficient vector of the segment interval.

[0109] The aforementioned satellite clock bias determination device based on inter-satellite links acquires inter-satellite link measurement data through acquisition unit 31, preprocesses the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and the observation inter-satellite distance between the first and second observation satellites at each observation time; the inter-satellite link data is segmented by segmentation unit 32 to obtain N segment intervals and inter-satellite link data for each segment interval, wherein N is a positive integer; the first calculation unit 33 calculates the observation residuals at each observation time within the segment intervals based on the inter-satellite link data of the segment intervals and the theoretical inter-satellite distances; the second calculation unit 34 calculates the clock bias coefficient vector within the segment intervals using statistical weighted least squares method based on the observation residuals at each observation time within the segment intervals; and the determination unit 35 determines the satellite clock bias of the first observation satellite and the second observation satellite within each segment interval based on the clock bias coefficient vector of the segment intervals.

[0110] In this embodiment, the nonlinear variation trend of the onboard clock is characterized by a higher-order polynomial, and the coefficients of the higher-order polynomial, i.e., the clock error coefficients, are fitted using the statistical weighted least squares method of the observation data. The clock error coefficients are then substituted into the higher-order polynomial to solve for the satellite clock error in each observation interval. The satellite clock error adopts a piecewise higher-order representation method, which allows for a more accurate description of the satellite clock error in each segment, thus achieving the goal of accurately calculating the satellite clock error. This achieves the technical effect of improving the accuracy of the satellite clock error calculation results, thereby solving the technical problem of low accuracy of related satellite clock error estimation technology in the complex background environment of Earth-Moon space.

[0111] Optionally, the segmentation unit 32 includes: a first acquisition module, used to acquire the observation duration of the entire observation process corresponding to the inter-satellite link data; and a first determination module, used to divide the inter-satellite link data based on the observation duration and the segmentation period to obtain N segment intervals and the inter-satellite link data of each segment interval.

[0112] Optionally, the satellite clock bias determination device based on inter-satellite links further includes: a first establishment module, used to establish a higher-order polynomial corresponding to the satellite clock bias of each segment interval, wherein the higher-order polynomial is expressed as: Where a(t) is the satellite clock error of the segmented interval, m represents the m-th segmented interval, and i represents the order. Let represent the coefficients of the i-th order polynomial of the satellite clock error within the m-th segment interval, and n represent the highest order of the polynomial.

[0113] Optionally, the first calculation unit 33 includes: a first extraction module, used to extract the observed inter-satellite distance at each observation time from the inter-satellite link data of the segmented interval; a first calculation module, used to transmit a signal from the first observation satellite to the second observation satellite at each observation time, calculate the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite, and calculate the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite; a second calculation module, used to calculate the theoretical inter-satellite distance at each observation time based on the first position vector and the second position vector; and a third calculation module, used to calculate the difference between the observed inter-satellite distance and the theoretical inter-satellite distance at each observation time, to obtain the observation residual at each observation time within the segmented interval.

[0114] Optionally, the second calculation unit 34 includes: a second establishment module, used to establish the observation equation for each observation time based on the observation residuals at each observation time, wherein the observation equation is expressed as: To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. This represents the clock error coefficient vector of the second observation satellite; the first fitting module is used to fit the observation equations at each observation time using the statistical weighted least squares method to obtain the clock error coefficient vector of the segmented interval.

[0115] Optionally, the determining unit 35 includes: a second extraction module, used to extract a first set of clock error coefficients for the first observation satellite from the clock error coefficient vector of the segmented interval; a fourth calculation module, used to substitute the first set of clock error coefficients into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval; a third extraction module, used to extract a second set of clock error coefficients for the second observation satellite from the clock error coefficient vector of the segmented interval; and a fifth calculation module, used to substitute the second set of clock error coefficients into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the second observation satellite in the segmented interval.

[0116] Optionally, the satellite clock bias determination device based on inter-satellite links further includes: a first detection module for detecting outliers in the inter-satellite link measurement data and removing the detected outliers; and a first processing module for smoothing the inter-satellite link measurement data and removing noise from the data.

[0117] The aforementioned satellite clock bias determination device based on inter-satellite links may also include a processor and a memory. The aforementioned acquisition unit 31, segmentation unit 32, first calculation unit 33, second calculation unit 34, determination unit 35, etc., are all stored in the memory as program units, and the processor executes the aforementioned program units stored in the memory to realize the corresponding functions.

[0118] The aforementioned processor contains a kernel, which retrieves the corresponding program units from memory. One or more kernels can be configured, and adjusting kernel parameters can improve the accuracy of satellite clock bias measurement and control.

[0119] The aforementioned memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0120] According to another aspect of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored computer program, wherein, when the computer program is running, it controls the device where the computer-readable storage medium is located to execute any of the above-described inter-satellite link-based satellite clock bias determination methods.

[0121] According to another aspect of the present invention, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement any of the above-described inter-satellite link-based satellite clock bias determination methods.

[0122] According to another aspect of the present invention, a computer program product is also provided, the computer program product including a computer program, wherein when the computer program is executed by a processor, it implements any of the above-described methods for determining satellite clock bias based on inter-satellite links.

[0123] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program with the following method steps: acquiring inter-satellite link measurement data; preprocessing the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and the observed inter-satellite distance between the first and second observation satellites at each observation time; segmenting the inter-satellite link data to obtain N segment intervals and inter-satellite link data for each segment interval, wherein N is a positive integer; calculating the observation residuals at each observation time within the segment intervals based on the inter-satellite link data and theoretical inter-satellite distances within the segment intervals; calculating the clock error coefficient vector within the segment intervals using the statistical weighted least squares method based on the observation residuals at each observation time within the segment intervals; and determining the satellite clock error of the first observation satellite and the second observation satellite within each segment interval based on the clock error coefficient vector of the segment intervals.

[0124] Optionally, the steps of segmenting the inter-satellite link data to obtain N segment intervals and the inter-satellite link data for each segment interval include: obtaining the observation duration of the entire observation process corresponding to the inter-satellite link data; determining the segment period based on the stability of the onboard clock; and dividing the inter-satellite link data based on the observation duration and the segment period to obtain N segment intervals and the inter-satellite link data for each segment interval.

[0125] Optionally, after segmenting the inter-satellite link data, the method further includes: establishing a higher-order polynomial corresponding to the satellite clock bias for each segment interval, wherein the higher-order polynomial is expressed as: Where a(t) is the satellite clock error of the segmented interval, m represents the m-th segmented interval, and i represents the order. Let represent the coefficients of the i-th order polynomial of the satellite clock error within the m-th segment interval, and n represent the highest order of the polynomial.

[0126] Optionally, the step of calculating the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distances includes: extracting the observation inter-satellite distances at each observation time from the inter-satellite link data of the segmented interval; transmitting a signal from the first observation satellite to the second observation satellite at each observation time, calculating the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite, and calculating the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite; calculating the theoretical inter-satellite distances at each observation time based on the first and second position vectors; and calculating the difference between the observation inter-satellite distances at each observation time and the theoretical inter-satellite distances to obtain the observation residuals at each observation time within the segmented interval.

[0127] Optionally, the step of calculating the clock error coefficient vector within the segmented interval using the statistical weighted least squares method based on the observation residuals at each observation time includes: establishing the observation equation for each observation time based on the observation residuals at each observation time, wherein the observation equation is expressed as: To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. This represents the clock error coefficient vector of the second observation satellite; the observation equations at each observation time are fitted and calculated using the statistical weighted least squares method to obtain the clock error coefficient vector for the segmented intervals.

[0128] Optionally, the steps of determining the satellite clock error of the first observation satellite and the satellite clock error of the second observation satellite in each segmented interval based on the clock error coefficient vector of the segmented interval include: extracting the first clock error coefficient set of the first observation satellite from the clock error coefficient vector of the segmented interval; substituting the first clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval; extracting the second clock error coefficient set of the second observation satellite from the clock error coefficient vector of the segmented interval; substituting the second clock error coefficient set into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the second observation satellite in the segmented interval.

[0129] Optionally, the preprocessing steps for inter-satellite link measurement data include: detecting outliers in the inter-satellite link measurement data and removing the detected outliers; and smoothing the inter-satellite link measurement data to remove noise from the data.

[0130] Figure 4 This is a hardware structure block diagram of an electronic device (or mobile device) that performs a satellite clock bias determination method based on inter-satellite links according to an embodiment of the present invention. Figure 4 As shown, an electronic device may include one or more processors ( Figure 4The processor, denoted by 402a, 402b, ..., 402n, can include, but is not limited to, a processing device such as a microprocessor (MCU) or a programmable logic device (FPGA), and a memory 404 for storing data. In addition, it may include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports in the I / O interface), a network interface, a keyboard, a power supply, and / or a camera. Those skilled in the art will understand that... Figure 4 The structure shown is for illustrative purposes only and does not limit the structure of the electronic device described above. For example, the electronic device may also include... Figure 4 The more or fewer components shown, or having the same Figure 4 The different configurations shown.

[0131] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0132] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0133] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0134] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0135] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0136] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0137] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for determining satellite clock bias based on inter-satellite links, characterized in that, include: Acquire inter-satellite link measurement data, preprocess the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and the observation inter-satellite distance between the first observation satellite and the second observation satellite at each observation time; The inter-satellite link data is segmented to obtain Each segment interval and the inter-satellite link data for each segment interval, wherein, It is a positive integer; Establish a higher-order polynomial corresponding to the satellite clock error for each of the segmented intervals, wherein the higher-order polynomial is expressed as: ,in, For the satellite clock bias of the segmented interval, Indicates the first Each segmented interval Indicates the order, Indicates the first The satellite clock error within each segmented interval Polynomial coefficients of order 1 This represents the highest order of the polynomial. The observation residuals at each observation time within the segmented intervals are calculated based on the inter-satellite link data and theoretical inter-satellite distances of the segmented intervals. Based on the observation residuals at each observation time within the segmented interval, the clock error coefficient vector within the segmented interval is calculated using the statistical weighted least squares method, including: establishing observation equations for each observation time based on the observation residuals at each observation time, wherein the observation equations are expressed as: , To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. This represents the clock bias coefficient vector of the second observation satellite. express The observed interstellar distance at any given time The theoretical inter-satellite distance at time t is represented; the clock error coefficient vector of the segmented interval is obtained by fitting the observation equation at each observation time using the statistical weighted least squares method. The satellite clock errors of the first observation satellite and the second observation satellite in each segmented interval are determined based on the clock error coefficient vector of the segmented interval.

2. The method according to claim 1, characterized in that, The inter-satellite link data is segmented to obtain The steps for dividing the segmented intervals and the inter-satellite link data for each segmented interval include: Obtain the observation duration of the entire observation process corresponding to the inter-satellite link data; The segmented period is determined based on the stability of the onboard clock; The inter-satellite link data is divided based on the observation duration and the segmentation period to obtain... Each of the segmented intervals and the inter-satellite link data for each of the segmented intervals.

3. The method according to claim 1, characterized in that, The steps for calculating the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distances include: Extract the observed inter-satellite distances at each observation time from the inter-satellite link data of the segmented intervals; At each of the aforementioned observation times, the first observation satellite transmits a signal to the second observation satellite, calculates the first position vector of the first observation satellite at the time of signal transmission based on the ephemeris data of the first observation satellite, and calculates the second position vector of the second observation satellite at the time of signal reception based on the ephemeris data of the second observation satellite. The theoretical inter-satellite distances at each observation time are calculated based on the first position vector and the second position vector; Calculate the difference between the observed inter-satellite distance and the theoretical inter-satellite distance at each observation time to obtain the observation residual for each observation time within the segmented interval.

4. The method according to claim 1, characterized in that, The steps for determining the satellite clock error of the first observation satellite and the satellite clock error of the second observation satellite in each segmented interval based on the clock error coefficient vector of the segmented interval include: Extract the first set of clock error coefficients for the first observation satellite from the clock error coefficient vector of the segmented interval; Substitute the first set of clock error coefficients into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock error of the first observation satellite in the segmented interval. Extract the second clock error coefficient set of the second observation satellite from the clock error coefficient vector of the segmented interval; The second set of clock bias coefficients is substituted into the higher-order polynomial of the corresponding segmented interval for calculation to obtain the satellite clock bias of the second observation satellite in that segmented interval.

5. The method according to claim 1, characterized in that, The steps for preprocessing the inter-satellite link measurement data include: Anomaly detection is performed on the inter-satellite link measurement data, and the detected anomalies are removed. The inter-satellite link measurement data is smoothed to remove noise.

6. A satellite clock bias determination device based on inter-satellite links, characterized in that, include: An acquisition unit is used to acquire inter-satellite link measurement data, preprocess the inter-satellite link measurement data to obtain inter-satellite link data, wherein the inter-satellite link data includes at least: observation time, and the observation inter-satellite distance between the first observation satellite and the second observation satellite at each observation time; The segmentation unit is used to segment the inter-satellite link data to obtain... Each segment interval and the inter-satellite link data for each segment interval, wherein, It is a positive integer; The inter-satellite link-based satellite clock bias determination device further includes: a first establishment module, used to establish a high-order polynomial corresponding to the satellite clock bias of each segmented interval, wherein the high-order polynomial is expressed as: ,in, For the satellite clock bias of the segmented interval, Indicates the first Each segmented interval Indicates the order, Indicates the first The satellite clock error within each segmented interval Polynomial coefficients of order 1 This represents the highest order of the polynomial. The first calculation unit is used to calculate the observation residuals at each observation time within the segmented interval based on the inter-satellite link data and theoretical inter-satellite distance of the segmented interval; The second calculation unit is used to calculate the clock error coefficient vector within the segmented interval based on the observation residuals at each observation time within the segmented interval using the statistical weighted least squares method. The second calculation unit includes: a second establishment module, used to establish the observation equation for each observation time based on the observation residuals at each observation time, wherein the observation equation is expressed as: , To observe the residuals, This represents the clock bias coefficient vector of the first observation satellite. This represents the clock bias coefficient vector of the second observation satellite. express The observed interstellar distance at any given time The theoretical inter-satellite distance at time t is represented; the first fitting module is used to fit the observation equations at each observation time using the statistical weighted least squares method to obtain the clock error coefficient vector of the segmented interval; The determining unit is used to determine the satellite clock difference of the first observation satellite in each of the segmented intervals and the satellite clock difference of the second observation satellite in each of the segmented intervals based on the clock difference coefficient vector of the segmented intervals.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the satellite clock bias determination method based on any one of claims 1 to 5.

8. An electronic device, characterized in that, It includes one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the inter-satellite link-based satellite clock bias determination method according to any one of claims 1 to 5.

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