A method, apparatus and medium for positioning a terminal by a low earth orbit satellite
Patent Information
- Application Number
- CN202611204559.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-10
- Publication Date
- 2026-10-09
AI Technical Summary
[0006]本公开的实施例提供了一种通过低轨卫星对终端进行定位的方法、装置及介质，以至少解决现有技术中存在的可能会出现低轨卫星的运动频率较快并且低轨卫星与终端之间的相对运动变化较为不稳定的情况，在这种情况下，将会降低通过低轨卫星对终端进行定位的准确性的技术问题
[0011]在本实施例中，终端可以获取多个低轨卫星与终端自身之间的多普勒频移数据，并根据多普勒频移数据，从第一定位方式和第二定位方式中选取出目标定位方式，以及通过目标定位方式对终端进行定位，其中，当目标定位方式为第一定位方式时，终端可以确定多个低轨卫星向终端发送信号的第一时长，并根据第一时长以及多个低轨卫星向终端发送信号时的位置，确定终端的位置。当目标定位方式为第二定位方式时，终端可以确定多个低轨卫星中的每个低轨卫星向终端发射信号的方向角度，并根据方向角度以及多个低轨卫星向终端发射信号时的位置，确定终端的位置。从而，在本实施例中，终端可以根据多普勒频移数据，确定每个低轨卫星与终端之间的相对运动情况，从而终端可以根据多普勒频移数据，选取出当前自身最适合的定位方式进行定位，例如若通过多普勒频移数据确定当前的相对运动情况不稳定，则可以选取精度更高的定位方式对自身进行定位，若通过多普勒频移数据确定当前的相对运动情况稳定，则可以选取精度较低但所需的计算成本也较低的定位方式对自身进行定位，从而本方法能够自适应选取更适合终端当前情况的定位方式，相比于现有技术，能够提高定位效果。
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Figure CN122883223A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of low-Earth orbit satellites and satellite positioning technology, and in particular to a method, apparatus and medium for locating a terminal using low-Earth orbit satellites. Background Technology
[0002] In traditional satellite positioning technology, high-orbit satellites are usually used. When positioning, the receiver receives observation signals such as pseudorange and carrier phase from at least multiple satellites, and solves simultaneous equations to calculate the receiver's positioning.
[0003] With the continuous development of satellite technology, low-Earth orbit (LEO) satellites can be used in satellite positioning technology. LEO satellites have advantages such as low orbital altitude, high operating speed, and flexible constellation networking, which can improve the satellite positioning effect compared with high-Earth orbit (GEO) satellites.
[0004] In existing technologies, satellite positioning via low-Earth orbit (LEO) satellites can follow traditional positioning methods. However, in LEO satellite positioning, there may be situations where the LEO satellites move at a relatively high frequency and the relative motion between the LEO satellites and the terminal is relatively unstable. In such cases, the accuracy of positioning the terminal via LEO satellites will be reduced.
[0005] The existing technology mentioned above may have issues such as the high frequency of low-Earth orbit (LEO) satellite movement and the relatively unstable motion between LEO satellites and terminals. In such cases, the accuracy of terminal positioning via LEO satellites will be reduced, and no effective solution has yet been proposed. Summary of the Invention
[0006] The embodiments of this disclosure provide a method, apparatus, and medium for locating a terminal using low-Earth orbit (LEO) satellites, at least addressing the technical problem in the prior art where the LEO satellites may move at a relatively high frequency and the relative motion between the LEO satellites and the terminal may be unstable, thus reducing the accuracy of locating the terminal using LEO satellites.
[0007] According to one aspect of the present disclosure, a method for locating a terminal using low-Earth orbit (LEO) satellites is provided, comprising: acquiring Doppler frequency shift data between a plurality of LEO satellites and the terminal; selecting a target positioning method from a first positioning method and a second positioning method based on the Doppler frequency shift data; and locating the terminal using the target positioning method, wherein the operation of locating the terminal using the target positioning method includes: when the target positioning method is the first positioning method, determining a first duration for which the plurality of LEO satellites transmit signals to the terminal, and determining the position of the terminal based on the first duration and the positions of the plurality of LEO satellites when transmitting signals to the terminal; and when the target positioning method is the second positioning method, determining the direction angle of each LEO satellite transmitting signals to the terminal, and determining the position of the terminal based on the direction angle and the positions of the plurality of LEO satellites when transmitting signals to the terminal.
[0008] According to another aspect of the present disclosure, a storage medium is also provided, the storage medium including a stored program, wherein, when the program is executed, a processor performs any of the methods described above.
[0009] According to another aspect of the present disclosure, an apparatus for locating a terminal using low-Earth orbit (LEO) satellites is also provided, comprising: an acquisition module for acquiring Doppler frequency shift data between a plurality of LEO satellites and the terminal; a positioning mode selection module for selecting a target positioning mode from a first positioning mode and a second positioning mode based on the Doppler frequency shift data; and a positioning module for locating the terminal using the target positioning mode, wherein the positioning module is configured to, when the target positioning mode is the first positioning mode, determine a first duration for which the plurality of LEO satellites transmit signals to the terminal, and determine the position of the terminal based on the first duration and the positions of the plurality of LEO satellites when transmitting signals to the terminal; and when the target positioning mode is the second positioning mode, determine the direction angle of each LEO satellite transmitting signals to the terminal, and determine the position of the terminal based on the direction angle and the positions of the plurality of LEO satellites when transmitting signals to the terminal.
[0010] According to another aspect of the present disclosure, an apparatus for locating a terminal via low-Earth orbit (LEO) satellites is also provided, comprising: a processor; and a memory connected to the processor, configured to provide the processor with instructions for processing the following steps: acquiring Doppler shift data between a plurality of LEO satellites and the terminal; selecting a target positioning method from a first positioning method and a second positioning method based on the Doppler shift data; and locating the terminal using the target positioning method, wherein the operation of locating the terminal using the target positioning method includes: when the target positioning method is the first positioning method, determining a first duration for which the plurality of LEO satellites transmit signals to the terminal, and determining the position of the terminal based on the first duration and the positions of the plurality of LEO satellites when transmitting signals to the terminal; and when the target positioning method is the second positioning method, determining the direction angle of each LEO satellite transmitting signals to the terminal, and determining the position of the terminal based on the direction angle and the positions of the plurality of LEO satellites when transmitting signals to the terminal.
[0011] In this embodiment, the terminal can acquire Doppler frequency shift data between itself and multiple low-Earth orbit (LEO) satellites, and select a target positioning method from a first positioning method and a second positioning method based on the Doppler frequency shift data. The terminal then positions itself using the target positioning method. Specifically, when the target positioning method is the first positioning method, the terminal can determine the first duration for which the multiple LEO satellites transmit signals to it, and determine its position based on the first duration and the positions of the multiple LEO satellites when transmitting signals. When the target positioning method is the second positioning method, the terminal can determine the direction angle of the signals transmitted from each of the multiple LEO satellites to it, and determine its position based on the direction angle and the positions of the multiple LEO satellites when transmitting signals. Therefore, in this embodiment, the terminal can determine the relative motion between each low-orbit satellite and the terminal based on Doppler frequency shift data. The terminal can then select the most suitable positioning method for itself based on the Doppler frequency shift data. For example, if the Doppler frequency shift data indicates that the current relative motion is unstable, a more accurate positioning method can be selected. If the Doppler frequency shift data indicates that the current relative motion is stable, a less accurate but less computationally expensive positioning method can be selected. Thus, this method can adaptively select the positioning method most suitable for the terminal's current situation, improving positioning performance compared to existing technologies. Attached Figure Description
[0012] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this application, illustrate exemplary embodiments of the present disclosure and are used to explain the disclosure, but do not constitute an undue limitation thereof. In the drawings: Figure 1This is a schematic diagram for implementing the satellite positioning system according to Embodiment 1 of this disclosure; Figure 2A This is a schematic diagram of a satellite according to Embodiment 1 of this disclosure; Figure 2B This is a schematic diagram of the terminal according to Embodiment 1 of this disclosure; Figure 3 This is a flowchart illustrating a method for locating a terminal using low-Earth orbit satellites according to the first aspect of Embodiment 1 of this disclosure; Figure 4 This is a schematic diagram of the direction angle according to the first aspect of Embodiment 1 of this disclosure; Figure 5 This is a schematic diagram of an apparatus for locating a terminal via a low-Earth orbit satellite according to the first aspect of Embodiment 2 of this disclosure; Figure 6 This is a schematic diagram of an apparatus for locating a terminal via a low-Earth orbit satellite, according to the first aspect of Embodiment 3 of this disclosure. Detailed Implementation
[0013] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.
[0014] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure 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 this disclosure 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 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.
[0015] Example 1
[0016] According to this embodiment, a method for locating a terminal via a low-Earth orbit satellite 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.
[0017] Figure 1 A schematic diagram of a satellite positioning system according to this embodiment is shown. The system includes: multiple low-Earth orbit (LEO) satellites and a terminal, wherein the multiple LEO satellites are used to provide positioning services for the terminal, that is, the terminal can locate itself through the multiple LEO satellites.
[0018] Figure 2A Further shown Figure 1 A schematic diagram of the hardware architecture of a low-to-medium Earth orbit satellite. (Reference) Figure 2A As shown, the satellite includes an integrated electronic system, which comprises a processor, a memory, a bus management module, and a communication interface. The memory is connected to the processor, allowing the processor to access the memory, read program instructions stored in the memory, and read or write data to the memory. The bus management module is connected to the processor and also to a bus such as a CAN bus. Thus, the processor can communicate with onboard peripherals connected to the bus through the bus managed by the bus management module. Furthermore, the processor also communicates with devices such as cameras, star sensors, telemetry and command transponders, and data transmission equipment via the communication interface. Those skilled in the art will understand that… Figure 2A The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, a satellite system may also include... Figure 2A The more or fewer components shown, or having the same Figure 2A The different configurations shown.
[0019] Figure 2B Further shown Figure 1 A schematic diagram of the hardware architecture of the mid-terminal. (Reference) Figure 2B As shown, the terminal may include one or more processors (processors may include, but are not limited to, microprocessors such as MCUs or programmable logic devices such as FPGAs), a memory for storing data, a transmission device for communication functions, and an input / output interface. The memory, transmission device, and input / output interface are connected to the processor via a bus. In addition, it may also include a display, keyboard, and cursor control device connected to the input / output interface. Those skilled in the art will understand that... Figure 2B The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, the terminal may also include... Figure 2BThe more or fewer components shown, or having the same Figure 2B The different configurations shown.
[0020] It should be noted that, Figure 2A and Figure 2B One or more processors and / or other data processing circuits shown herein may generally be referred to as "data processing circuitry". This data processing circuitry may be embodied, in whole or in part, in software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuitry may be a single, independent processing module, or may be integrated, in whole or in part, into any other element in a computing device. As involved in embodiments of this disclosure, the data processing circuitry serves as processor control (e.g., selection of a variable resistor termination path connected to an interface).
[0021] Figure 2A and Figure 2B The memory shown can be used to store software programs and modules of application software, such as the program instruction / data storage device corresponding to the method of locating a terminal via low-Earth orbit satellites in this embodiment of the present disclosure. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory, thereby realizing the above-mentioned method of locating a terminal via low-Earth orbit satellites. The memory may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory.
[0022] It should be noted here that, in some optional embodiments, the above... Figure 2A and Figure 2B The device shown may include hardware elements (including circuitry), software elements (including computer code stored on a computer-readable medium), or a combination of both hardware and software elements. It should be noted that... Figure 2A and Figure 2B This is only one instance of a specific particular instance, and is intended to illustrate the types of components that may exist in the aforementioned devices.
[0023] Under the aforementioned operating environment, according to the first aspect of this embodiment, a method for locating a terminal via low-Earth orbit satellites is provided. This method comprises... Figure 1 The terminal implementation shown. Figure 3 A flowchart illustrating the method is shown below. (Refer to...) Figure 3 As shown, the method includes: S302: Acquire Doppler shift data between multiple low-Earth orbit satellites and the terminal; S304: Based on the Doppler frequency shift data, select the target positioning method from the first positioning method and the second positioning method; and S306: The terminal is located by target positioning.
[0024] Specifically, refer to Figure 3 As shown, firstly, the terminal can acquire Doppler frequency shift data between multiple low-orbit satellites and the terminal (S302).
[0025] Among them, the Doppler shift data between a low-Earth orbit satellite and a terminal can represent the relative motion between the corresponding low-Earth orbit satellite and the terminal.
[0026] The terminal can obtain the signal sent to it by the low-orbit satellite at any sampling time, and determine the Doppler frequency shift data between the low-orbit satellite and itself at the corresponding sampling time based on the difference between the transmission frequency of the low-orbit satellite signal and the reception frequency of the signal received by itself.
[0027] Then, the terminal can select the target positioning method from the first positioning method and the second positioning method based on the Doppler frequency shift data (S304), and locate the terminal according to the target positioning method.
[0028] Specifically, the terminal can select a target positioning method from the first and second positioning methods based on Doppler frequency shift data. In other words, Doppler frequency shift data can represent the relative motion between the low-Earth orbit (LEO) satellite and the terminal. Determining multiple Doppler frequency shift data points between the LEO satellite and the terminal over a period of time can represent the relative motion between them during that period. For example, Doppler frequency shift data can determine whether the relative motion between the LEO satellite and the terminal is stable or changing drastically. Therefore, the terminal can determine the most suitable positioning method based on the Doppler frequency shift data, i.e., select the target positioning method, and then use that method to locate itself.
[0029] In this embodiment, two positioning methods are provided: a first positioning method and a second positioning method. The second positioning method has higher accuracy than the first positioning method, but also consumes more computational resources. Therefore, when the terminal selects the first positioning method based on Doppler frequency shift data, it indicates that the terminal's relative motion with the low-Earth orbit satellite is relatively stable. When the terminal selects the second positioning method based on Doppler frequency shift data, it indicates that the terminal's relative motion with the low-Earth orbit satellite is jittery (i.e., the relative motion between the terminal and the low-Earth orbit satellite is unstable).
[0030] When the target positioning method is the first positioning method, the terminal can determine the first duration for which multiple low-Earth orbit (LEO) satellites transmit signals to the terminal, and determine the terminal's position based on the first duration and the positions of the multiple LEO satellites when transmitting signals to the terminal. When the target positioning method is the second positioning method, the terminal can determine the direction angle of the signal transmitted from each of the multiple LEO satellites to the terminal, and determine the terminal's position based on the direction angle and the positions of the multiple LEO satellites when transmitting signals to the terminal. Here, the direction angle of the signal transmitted from the LEO satellites to the terminal refers to the angle of the beam when the LEO satellite transmits the signal to the terminal.
[0031] The first and second positioning methods will be explained in detail later.
[0032] As described in the background section, in the prior art, satellite positioning via low-Earth orbit (LEO) satellites can follow traditional positioning methods. However, in LEO satellite positioning, there may be situations where the LEO satellites move at a relatively high frequency and the relative motion between the LEO satellites and the terminal is relatively unstable. In such cases, the accuracy of positioning the terminal via LEO satellites will be reduced.
[0033] Therefore, in this embodiment, the terminal can acquire Doppler frequency shift data between itself and multiple low-Earth orbit (LEO) satellites, and select a target positioning method from a first positioning method and a second positioning method based on the Doppler frequency shift data. The terminal then positions itself using the target positioning method. Specifically, when the target positioning method is the first positioning method, the terminal can determine the first duration for which multiple LEO satellites transmit signals to it, and determine its position based on the first duration and the positions of the multiple LEO satellites when transmitting signals. When the target positioning method is the second positioning method, the terminal can determine the direction angle of each LEO satellite transmitting signals to it, and determine its position based on the direction angle and the positions of the multiple LEO satellites when transmitting signals.
[0034] Therefore, in this embodiment, the terminal can determine the relative motion between each low-orbit satellite and the terminal based on Doppler frequency shift data. The terminal can then select the most suitable positioning method for itself based on the Doppler frequency shift data. For example, if the Doppler frequency shift data indicates that the current relative motion is unstable, a more accurate positioning method can be selected. If the Doppler frequency shift data indicates that the current relative motion is stable, a less accurate but less computationally expensive positioning method can be selected. Thus, this method can adaptively select the positioning method most suitable for the terminal's current situation, improving positioning performance compared to existing technologies.
[0035] Optionally, the operation of selecting a target positioning method from the first positioning method and the second positioning method based on the Doppler frequency shift data includes: for each of the multiple low-Earth orbit satellites, determining at least two Doppler frequency shift data with different sampling times between the corresponding low-Earth orbit satellite and the terminal, and determining the rate of change of the at least two Doppler frequency shift data; if the rate of change corresponding to any one of the low-Earth orbit satellites is lower than a preset threshold, using the first positioning method as the target positioning method; and if the rate of change corresponding to multiple low-Earth orbit satellites is higher than a preset threshold, using the second positioning method as the target positioning method.
[0036] Specifically, for each of the multiple low-Earth orbit (LEO) satellites, the terminal can determine at least two Doppler frequency shift data points with different sampling times between the corresponding LEO satellite and the terminal itself, and determine the rate of change of at least two Doppler frequency shift data points. The sampling time can, for example, refer to the time it takes for the terminal to acquire the signal used to determine the Doppler frequency shift data.
[0037] For example, two Doppler frequency shift data with different sampling times can be directly obtained, and the rate of change of the corresponding Doppler frequency shift data can be determined. The following formula shows the calculation method of the corresponding rate of change:
[0038]
[0039] This represents the rate of change of the Doppler frequency shift data. This can represent the Doppler frequency shift data sampled at the first sampling time. It can represent the Doppler frequency shift data sampled at the second sampling time. This indicates the time interval between the first sampling time and the second sampling time.
[0040] Optionally, the operation of determining the terminal's position based on the direction angle and the positions of multiple low-Earth orbit satellites transmitting signals to the terminal includes: constructing a first equation based on the direction angle of any one of the multiple low-Earth orbit satellites transmitting signals to the terminal and the position of the corresponding low-Earth orbit satellite transmitting signals to the terminal; selecting a reference satellite from the multiple low-Earth orbit satellites and determining a second duration for the reference satellite to transmit signals to the terminal; determining a third duration for the other satellites (excluding the reference satellite) to transmit signals to the terminal; determining a second equation based on the duration difference between the second and third durations, the position of the reference satellite transmitting signals to the terminal, and the positions of the other satellites transmitting signals to the terminal; determining a first set of equations based on the first equation and a second set of equations based on the second equation; and solving for the terminal's position based on the first set of equations and the second set of equations.
[0041] Alternatively, the expression for the first equation is:
[0042] in, Indicates the first The angle of direction from which a low-orbit satellite transmits a signal to a terminal, ( , , ) indicates the first The location of a low-orbit satellite, ( , , () indicates the location of the terminal.
[0043] Specifically, when the terminal uses the second positioning method for positioning, it is necessary to construct a first equation and a second equation respectively. The first equation is related to the beam angle constraint, and the second equation is related to the time delay difference constraint.
[0044] The terminal can construct the first equation based on the direction and angle of the signal transmitted from any one of the multiple low-Earth orbit satellites to the terminal, as well as the position of the corresponding low-Earth orbit satellite when transmitting the signal to the terminal.
[0045] The expression for the first equation is:
[0046] in, Indicates the first The angle of direction from which a low-orbit satellite transmits a signal to a terminal, ( , , ) indicates the first The location of a low-orbit satellite when it sends a signal to the terminal, ( , , () indicates the location of the terminal.
[0047] in, and( , , The information can be carried in the first... The signals sent from a low-orbit satellite to the terminal. This refers to the angle of the beam when a low-Earth orbit (LEO) satellite transmits a signal to a terminal. LEO satellites typically switch beam angles (i.e., switch beam positions) according to a certain pattern; therefore, the beam angle transmitted by a LEO satellite at any given moment can be determined by the LEO satellite itself.
[0048] In this embodiment, specifically, three low-Earth orbit satellites may provide positioning services to the terminal. Therefore, the expression for the first set of equations determined by the first equation above is:
[0049] In other words, each of the first equations in the above first set of equations corresponds to a low-Earth orbit satellite. , , These represent the directional angles corresponding to the three low-Earth orbit satellites, ( , , ), ( , , )as well as( , , These represent the positions of the three low-Earth orbit satellites when they transmit signals to the terminal. (Reference) Figure 4 As shown, Figure 4 This shows the directional angle when a low-Earth orbit satellite sends a signal to a terminal. A schematic diagram. This direction angle. This can be understood as the directional angle of the low-Earth orbit (LEO) satellite's beam when transmitting signals to a terminal. Since a LEO satellite can directly determine the directional angle of its own beam transmission at a given moment, it can thus determine the corresponding directional angle. Continue to refer to Figure 4 As shown, direction angle This can be represented by the positions of the low-Earth orbit satellite and the terminal, i.e., the direction and angle. It can be expressed by the formula on the right side of the first equation above. Therefore, the first equation above can be obtained by beam angle constraints, and then the first set of equations above can be obtained.
[0050] The position of the terminal can be directly solved using the first set of equations formed by the first equation above. , , However, in order to further eliminate clock errors, a second set of equations is introduced, and the position of the terminal is determined by the time delay difference constraint of the second set of equations and the beam angle constraint of the first set of equations.
[0051] Specifically, the terminal can select a reference satellite from multiple low-Earth orbit satellites and determine a second duration for the reference satellite to send signals to the terminal; for other low-Earth orbit satellites besides the reference satellite, determine a third duration for the other satellites to send signals to the terminal; and determine a second equation based on the duration difference between the second and third durations, the position of the reference satellite when sending signals to the terminal, and the positions of the other satellites when sending signals to the terminal.
[0052] The expression for the second equation is:
[0053] in,( , , ) indicates the location of the reference satellite when it sends a signal to the terminal. , , This indicates the position of any one of the multiple low-Earth orbit satellites (excluding the reference satellite) when it transmits a signal to the terminal. This represents the time difference between the second duration of the reference satellite transmitting signals to the terminal and the third duration of the corresponding signals transmitted by other satellites to the terminal. This represents the speed of free-space radio propagation (i.e., the speed of light).
[0054] The second system of equations can be expressed as:
[0055] Since three low-Earth orbit satellites are used to locate the terminal in this embodiment, the two second equations in the above-mentioned second equation set correspond to two other satellites besides the reference satellite, respectively. , , ) indicates the location of the reference satellite when it sends a signal to the terminal. , , )and( , , These represent the positions of two satellites (excluding the reference satellite) when they transmit signals to the terminal. and These represent the time difference between two satellites other than the reference satellite.
[0056] Therefore, based on the first and second sets of equations mentioned above, the location of the terminal can be determined. , , ).
[0057] It should be noted that the position of the terminal can be determined using Newton's iteration method, based on the first and second sets of equations mentioned above.
[0058] First, a residual vector can be constructed. , in, and Represents the time delay difference residual. , and Represents beam angle residual. Time delay residual. It can be determined by the following expression:
[0059]
[0060] It can be seen that, Equivalent to the left side of the equals sign in the second equation. This is equivalent to the right side of the equals sign in the second equation.
[0061] Beam angle residual It can be determined by the following expression:
[0062]
[0063] It can be seen that, This is equivalent to the right-hand side of the equals sign in the first equation. This is equivalent to the left side of the equals sign in the first equation.
[0064] Then, based on the aforementioned time delay difference residual and beam angle residual Constructing the Jacobian matrix :
[0065] The first two rows of the above matrix represent the time delay difference residual. With terminal location ( , , The partial derivatives between the two lines are shown in the last three lines, which represent the beam angle residuals. With terminal location ( , , The partial derivative relationship between ) is given. Therefore, Newton's iteration method can be performed using the Jacobian matrix described above, where the correction factor for the iteration is set as: In the iteration, the objective is to determine the residual time delay difference. and beam angle residual Terminal positions that are all close to 0 ( , , ).
[0066] First, we can initialize and determine the initial value of the terminal position. .
[0067] Then, in each iteration, the coordinates of the terminal position of the current iteration are... Substitute the time delay difference residual and beam angle residual The calculation formula yields the residual vector of the current round. Residual vector This indicates the overall error. This indicates the iteration round. Then, the correction amount for the current round is determined. ,in, This represents the Jacobian matrix for the current iteration. The coordinates of the terminal position in the current iteration are obtained through the correction value of the current iteration. Update the coordinates to generate the next round's terminal location coordinates. .
[0068] Finally, during iterative convergence, the coordinates of the terminal position determined in the last iteration can be used as the solved terminal coordinates. For example, one could use... A value below a preset threshold is used as a convergence condition.
[0069] The first positioning method is described below. The first positioning method is pseudorange positioning.
[0070] The terminal uses the following third-party program group to determine the terminal's location through the first positioning method.
[0071]
[0072] Among them, the above three equations correspond to three low-orbit satellites, ( , , ) indicates the location of the terminal, ( , , ), ( , , )as well as( , , These represent the positions of the low-Earth orbit satellites when they send signals to the terminal. , as well as These represent the duration of signals transmitted from the three low-orbit satellites to the terminal (first duration).
[0073] As can be seen from the descriptions of the first and second positioning methods, the first positioning method is easier to solve and has a lower computational cost than the second positioning method. However, the second positioning method has more types of constraints and involves angles, so it has higher accuracy but also a relatively higher computational cost.
[0074] In addition, refer to Figure 1 As shown, according to a second aspect of this embodiment, a storage medium is provided. The storage medium includes a stored program, wherein, when the program is executed, a processor performs any of the methods described above.
[0075] Therefore, according to this embodiment, based on the time-domain rate of change of the Doppler frequency shift between the low-Earth orbit satellite and the terminal, it is determined which positioning method should be used. When the relative motion between the low-Earth orbit satellite and the terminal is stable, the first positioning method is used. The first positioning method is easier to solve than the second positioning method, has lower computational cost, and is more suitable for the case of stable relative motion. When the relative motion between the low-Earth orbit satellite and the terminal is unstable, the second positioning method is used. The second positioning method, which combines beam angle constraints and time delay difference constraints, has higher positioning accuracy, but also requires higher computational cost. Therefore, in this embodiment, it can adapt to the motion law of low-Earth orbit satellites and adaptively switch to the appropriate positioning method, solving the problem that a single positioning algorithm cannot simultaneously take into account both accuracy and computational power.
[0076] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.
[0077] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.
[0078] Example 2
[0079] Figure 5 An apparatus for locating a terminal via a low-Earth orbit satellite according to a first aspect of this embodiment is shown, corresponding to the method described according to the first aspect of Embodiment 1. (See reference...) Figure 5As shown, the device includes: an acquisition module 510 for acquiring Doppler frequency shift data between multiple low-Earth orbit satellites and a terminal; a positioning mode selection module 520 for selecting a target positioning mode from a first positioning mode and a second positioning mode based on the Doppler frequency shift data; and a positioning module 530 for positioning the terminal using the target positioning mode. Specifically, when the target positioning mode is the first positioning mode, the positioning module 530 determines a first duration for which multiple low-Earth orbit satellites transmit signals to the terminal, and determines the terminal's position based on the first duration and the positions of the multiple low-Earth orbit satellites when transmitting signals to the terminal; and when the target positioning mode is the second positioning mode, it determines the direction angle of each low-Earth orbit satellite transmitting signals to the terminal, and determines the terminal's position based on the direction angle and the positions of the multiple low-Earth orbit satellites when transmitting signals to the terminal.
[0080] Optionally, the positioning mode selection module 520 is used to determine, for each of the multiple low-orbit satellites, at least two Doppler frequency shift data with different sampling times between the corresponding low-orbit satellite and the terminal, and to determine the rate of change of the at least two Doppler frequency shift data; if the rate of change corresponding to any one low-orbit satellite is lower than a preset threshold, the first positioning mode is used as the target positioning mode; and if the rate of change corresponding to multiple low-orbit satellites is higher than a preset threshold, the second positioning mode is used as the target positioning mode.
[0081] Optionally, the positioning module 530 is used to construct a first equation based on the direction angle of a signal transmitted from any one of the multiple low-orbit satellites to the terminal and the position of the corresponding low-orbit satellite when transmitting the signal to the terminal; select a reference satellite from the multiple low-orbit satellites and determine a second duration for the reference satellite to transmit the signal to the terminal; determine a third duration for the other satellites (excluding the reference satellite) to transmit the signal to the terminal; determine a second equation based on the duration difference between the second and third durations, the position of the reference satellite when transmitting the signal to the terminal, and the positions of the other satellites when transmitting the signal to the terminal; determine a first set of equations based on the first equation and a second set of equations based on the second equation; and solve for the position of the terminal based on the first set of equations and the second set of equations.
[0082] Alternatively, the expression for the first equation is:
[0083] in, Indicates the first The angle of direction from which a low-orbit satellite transmits a signal to a terminal, ( , , ) indicates the first The location of a low-orbit satellite, ( , , () indicates the location of the terminal.
[0084] Optionally, multiple low-Earth orbit satellites may be converted into three low-Earth orbit satellites.
[0085] Therefore, according to this embodiment, based on the time-domain rate of change of the Doppler frequency shift between the low-Earth orbit satellite and the terminal, it is determined which positioning method should be used. When the relative motion between the low-Earth orbit satellite and the terminal is stable, the first positioning method is used. The first positioning method is easier to solve than the second positioning method, has lower computational cost, and is more suitable for the case of stable relative motion. When the relative motion between the low-Earth orbit satellite and the terminal is unstable, the second positioning method is used. The second positioning method, which combines beam angle constraints and time delay difference constraints, has higher positioning accuracy, but also requires higher computational cost. Therefore, in this embodiment, it can adapt to the motion law of low-Earth orbit satellites and adaptively switch to the appropriate positioning method, solving the problem that a single positioning algorithm cannot simultaneously take into account both accuracy and computational power.
[0086] Example 3
[0087] Figure 6 An apparatus for locating a terminal via a low-Earth orbit satellite according to a first aspect of this embodiment is shown, corresponding to the method described according to the first aspect of Embodiment 1. Reference Figure 6 As shown, the device includes: a processor 610; and a memory 620 connected to the processor 610, for providing the processor 610 with instructions to process the following steps: acquiring Doppler frequency shift data between a plurality of low-Earth orbit satellites and a terminal; selecting a target positioning method from a first positioning method and a second positioning method based on the Doppler frequency shift data; positioning the terminal using the target positioning method, wherein the operation of positioning the terminal using the target positioning method includes: when the target positioning method is the first positioning method, determining a first duration for which the plurality of low-Earth orbit satellites transmit signals to the terminal, and determining the position of the terminal based on the first duration and the positions of the plurality of low-Earth orbit satellites when transmitting signals to the terminal; and when the target positioning method is the second positioning method, determining the direction angle of the signal transmitted by each of the plurality of low-Earth orbit satellites to the terminal, and determining the position of the terminal based on the direction angle and the positions of the plurality of low-Earth orbit satellites when transmitting signals to the terminal.
[0088] Optionally, the operation of selecting a target positioning method from the first positioning method and the second positioning method based on the Doppler frequency shift data includes: for each of the multiple low-Earth orbit satellites, determining at least two Doppler frequency shift data with different sampling times between the corresponding low-Earth orbit satellite and the terminal, and determining the rate of change of the at least two Doppler frequency shift data; if the rate of change corresponding to any one of the low-Earth orbit satellites is lower than a preset threshold, using the first positioning method as the target positioning method; and if the rate of change corresponding to multiple low-Earth orbit satellites is higher than a preset threshold, using the second positioning method as the target positioning method.
[0089] Optionally, the operation of determining the terminal's position based on the direction angle and the positions of multiple low-Earth orbit satellites transmitting signals to the terminal includes: constructing a first equation based on the direction angle of any one of the multiple low-Earth orbit satellites transmitting signals to the terminal and the position of the corresponding low-Earth orbit satellite transmitting signals to the terminal; selecting a reference satellite from the multiple low-Earth orbit satellites and determining a second duration for the reference satellite to transmit signals to the terminal; determining a third duration for the other satellites (excluding the reference satellite) to transmit signals to the terminal; determining a second equation based on the duration difference between the second and third durations, the position of the reference satellite transmitting signals to the terminal, and the positions of the other satellites transmitting signals to the terminal; determining a first set of equations based on the first equation and a second set of equations based on the second equation; and solving for the terminal's position based on the first set of equations and the second set of equations.
[0090] Alternatively, the expression for the first equation is:
[0091] in, Indicates the first The angle of direction from which a low-orbit satellite transmits a signal to a terminal, ( , , ) indicates the first The location of a low-orbit satellite, ( , , () indicates the location of the terminal.
[0092] Optionally, multiple low-Earth orbit satellites may be converted into three low-Earth orbit satellites.
[0093] Therefore, according to this embodiment, based on the time-domain rate of change of the Doppler frequency shift between the low-Earth orbit satellite and the terminal, it is determined which positioning method should be used. When the relative motion between the low-Earth orbit satellite and the terminal is stable, the first positioning method is used. The first positioning method is easier to solve than the second positioning method, has lower computational cost, and is more suitable for the case of stable relative motion. When the relative motion between the low-Earth orbit satellite and the terminal is unstable, the second positioning method is used. The second positioning method, which combines beam angle constraints and time delay difference constraints, has higher positioning accuracy, but also requires higher computational cost. Therefore, in this embodiment, it can adapt to the motion law of low-Earth orbit satellites and adaptively switch to the appropriate positioning method, solving the problem that a single positioning algorithm cannot simultaneously take into account both accuracy and computational power.
[0094] 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.
[0095] 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.
[0096] 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 is only a logical functional division, and in actual implementation, there may be other division methods. For example, 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.
[0097] 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 network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0098] 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.
[0099] 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.
[0100] 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 locating a terminal using low-Earth orbit satellites, characterized in that, include: Acquire Doppler shift data between multiple low-Earth orbit satellites and the terminal; Based on the Doppler frequency shift data, a target positioning method is selected from the first positioning method and the second positioning method; The terminal is located using the target positioning method, and the operation of locating the terminal according to the target positioning method includes: When the target positioning method is the first positioning method, a first duration for which the plurality of low-orbit satellites transmit signals to the terminal is determined, and the position of the terminal is determined based on the first duration and the positions of the plurality of low-orbit satellites when transmitting signals to the terminal; and When the target positioning method is the second positioning method, the direction angle of the signal transmitted from each of the plurality of low-orbit satellites to the terminal is determined, and the position of the terminal is determined according to the direction angle and the position of the plurality of low-orbit satellites when transmitting signals to the terminal.
2. The method according to claim 1, characterized in that, The operation of selecting a target positioning method from the first positioning method and the second positioning method based on the Doppler frequency shift data includes: For each of the plurality of low-Earth orbit satellites, at least two Doppler frequency shift data with different sampling times between the corresponding low-Earth orbit satellite and the terminal are determined, and the rate of change of the at least two Doppler frequency shift data is determined; If the rate of change corresponding to any low-Earth orbit satellite is lower than a preset threshold, the first positioning method will be used as the target positioning method; and If the rate of change corresponding to the plurality of low-orbit satellites is higher than a preset threshold, the second positioning method shall be used as the target positioning method.
3. The method according to claim 1, characterized in that, The operation of determining the location of the terminal based on the directional angle and the positions of the plurality of low-orbit satellites when transmitting signals to the terminal includes: Based on the direction angle of the signal transmitted from any one of the multiple low-orbit satellites to the terminal and the position of the corresponding low-orbit satellite when transmitting the signal to the terminal, a first equation is constructed. A reference satellite is selected from the plurality of low-Earth orbit satellites, and a second duration for the reference satellite to transmit signals to the terminal is determined; For the other satellites among the plurality of low-orbit satellites besides the reference satellite, a third duration for the other satellites to transmit signals to the terminal is determined; The second equation is determined based on the time difference between the second and third durations, the position of the reference satellite when it sends a signal to the terminal, and the positions of the other satellites when they send signals to the terminal. The first set of equations is determined based on the first equation, and the second set of equations is determined based on the second equation; and The position of the terminal is determined based on the first set of equations and the second set of equations.
4. The method according to claim 3, characterized in that, The expression for the first equation is: in, Indicates the first The direction and angle of the signal transmitted from the low-orbit satellite to the terminal, ( , , ) indicates the first The location of a low-orbit satellite, ( , , () indicates the location of the terminal.
5. The method according to claim 1, characterized in that, The multiple low-orbit satellites refer to three low-orbit satellites.
6. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, the method described in any one of claims 1 to 5 is performed by a processor.
7. A device for locating a terminal via low-Earth orbit satellites, characterized in that, include: The acquisition module is used to acquire Doppler frequency shift data between multiple low-Earth orbit satellites and the terminal; The positioning method selection module is used to select a target positioning method from a first positioning method and a second positioning method based on the Doppler frequency shift data. A positioning module is used to locate the terminal using the target positioning method, and wherein, when the target positioning method is the first positioning method, the positioning module is used to determine the first duration of the signals transmitted to the terminal by the plurality of low-orbit satellites, and to determine the location of the terminal based on the first duration and the positions of the plurality of low-orbit satellites when transmitting signals to the terminal; as well as When the target positioning method is the second positioning method, the direction angle of the signal transmitted from each of the plurality of low-orbit satellites to the terminal is determined, and the position of the terminal is determined according to the direction angle and the position of the plurality of low-orbit satellites when transmitting signals to the terminal.
8. The apparatus according to claim 7, characterized in that, The positioning mode selection module is used to determine, for each of the plurality of low-Earth orbit satellites, at least two Doppler frequency shift data with different sampling times between the corresponding low-Earth orbit satellite and the terminal, and to determine the rate of change of the at least two Doppler frequency shift data; if the rate of change corresponding to any low-Earth orbit satellite is lower than a preset threshold, the first positioning mode is used as the target positioning mode; and if the rate of change corresponding to the plurality of low-Earth orbit satellites is higher than the preset threshold, the second positioning mode is used as the target positioning mode.
9. The apparatus according to claim 7, characterized in that, The positioning module is used to construct a first equation based on the direction angle of the signal transmitted from any one of the plurality of low-orbit satellites to the terminal and the position of the corresponding low-orbit satellite when transmitting the signal to the terminal; A reference satellite is selected from the plurality of low-Earth orbit satellites, and a second duration for the reference satellite to transmit signals to the terminal is determined; for the other low-Earth orbit satellites besides the reference satellite, a third duration for the other satellites to transmit signals to the terminal is determined; a second equation is determined based on the duration difference between the second duration and the third duration, the position of the reference satellite when transmitting signals to the terminal, and the positions of the other satellites when transmitting signals to the terminal; a first set of equations is determined based on the first equation, and a second set of equations is determined based on the second equation; And the position of the terminal is determined based on the first set of equations and the second set of equations.
10. A device for locating a terminal via low-Earth orbit satellites, characterized in that, include: processor; as well as A memory, connected to the processor, for providing the processor with instructions to perform the following processing steps: Acquire Doppler shift data between multiple low-Earth orbit satellites and the terminal; Based on the Doppler frequency shift data, a target positioning method is selected from the first positioning method and the second positioning method; The terminal is located using the target positioning method, and the operation of locating the terminal according to the target positioning method includes: When the target positioning method is the first positioning method, a first duration for which the plurality of low-orbit satellites transmit signals to the terminal is determined, and the position of the terminal is determined based on the first duration and the positions of the plurality of low-orbit satellites when transmitting signals to the terminal; and When the target positioning method is the second positioning method, the direction angle of the signal transmitted from each of the plurality of low-orbit satellites to the terminal is determined, and the position of the terminal is determined based on the direction angle and the position of the plurality of low-orbit satellites when transmitting signals to the terminal.