Positioning methods, devices, and electronic equipment for users on the lunar surface

Abstract

This invention provides a positioning method, device, and electronic device for users on the lunar surface. The positioning method includes: a user device located on the lunar surface transmitting electromagnetic wave signals to a lunar satellite; receiving electromagnetic wave signals reflected back by the satellite and recording the round-trip time t between the user device and the satellite; calculating the distance d between the user device and the satellite based on the round-trip time t, where d = c·t / 2, and c is the speed of light; and calculating the user's coordinates on the lunar surface using the tri-sphere intersection positioning principle after obtaining the distances between at least three satellites and the user device, combined with the coordinates of each satellite. This invention enables precise user positioning in a lunar environment, requires lower costs, simplifies lunar satellite payload configuration, and can meet the needs of future lunar exploration.

Description

Technical Field

[0001] This invention relates primarily to the field of satellite positioning and navigation technology, and more particularly to a positioning method, device, and electronic device for users on the lunar surface. Background Technology

[0002] The basic principle of satellite positioning is to receive signals transmitted by satellites, calculate the distance between the receiver and the satellite, and then determine the receiver's location on Earth. Since the satellite's position is precisely known, the location of the observation point can be solved by measuring the distance from the satellite to the receiver and using the distance formula in three-dimensional coordinates.

[0003] Lunar satellite positioning technology is one of the key technologies in lunar exploration activities. Its development will provide crucial support for future lunar exploration activities, including real-time, high-precision navigation and positioning support for lunar surface activities, landings, and takeoffs, enhancing the feasibility and safety of long-term human lunar exploration. However, GNSS (Global Navigation Satellite System) systems are designed for near-Earth space users. For example, the existing BeiDou-3 navigation system serves areas below 1000km in low Earth orbit. For the Moon, the degraded geometry of Earth navigation satellite constellations, the adopted spatiotemporal reference framework, and the methods for measuring, determining, and transmitting spatiotemporal information are no longer applicable. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a positioning method, device and electronic equipment for users on the lunar surface, which is low in cost and simplifies the configuration of lunar satellite payloads.

[0005] To address the aforementioned technical problems, in a first aspect, the present invention provides a method for locating a user on the lunar surface, comprising: a user device located on the lunar surface transmitting an electromagnetic wave signal to a lunar satellite; receiving an electromagnetic wave signal reflected back by the satellite and recording the round-trip time t between the user device and the satellite; calculating the distance d between the user device and the satellite based on the round-trip time t, where d = c·t / 2, and c is the speed of light; and, after obtaining the distances between the user device and at least three satellites, calculating the user's coordinates on the lunar surface using the tri-sphere intersection positioning principle in conjunction with the coordinates of each satellite.

[0006] Optionally, the satellite is a satellite within a constructed space segment, which consists of 4 NRHO orbit satellites and 24 ELFO orbit satellites.

[0007] Optionally, the electromagnetic wave signal is a laser signal.

[0008] Optionally, the user equipment is equipped with a high-precision clock and a laser ranging device, and the satellite is equipped with a laser corner reflector.

[0009] Optionally, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle, including: if three satellites are used for positioning, the user coordinates on the lunar surface can be calculated using the following set of equations:

[0010]

[0011] In the formula, (x1,y1) are the coordinates of the first satellite, (x2,y2) are the coordinates of the second satellite, (x3,y3) are the coordinates of the third satellite, (x,y,z) are the coordinates of the user on the lunar surface, and t1, t2, and t3 are the round-trip times recorded by the three satellites, respectively.

[0012] Optionally, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle, including: if four or more satellites are used for positioning, the user's coordinates (x, y, z) on the lunar surface can be solved numerically, satisfying:

[0013]

[0014] In the formula, n represents n satellites, n≥4, (x i ,y i ,z i Let d be the coordinates of the i-th satellite. i Let be the distance between the i-th satellite and the user equipment.

[0015] Optionally, it also includes: using Kalman filtering to correct the calculated coordinates of the lunar surface user.

[0016] Secondly, the present invention provides a positioning device for a user on the lunar surface, comprising: a signal transmitting module for transmitting electromagnetic wave signals from a user device located on the lunar surface to a lunar satellite; a signal receiving module for receiving electromagnetic wave signals reflected back by the satellite and recording the round-trip time t between the user device and the satellite; a first calculation module for calculating the distance d between the user device and the satellite based on the round-trip time t, where d = c·t / 2, and c is the speed of light; and a second calculation module for calculating the user's coordinates on the lunar surface by combining the coordinates of each of the at least three satellites with the coordinates of the user device, using the principle of tri-sphere rendezvous positioning.

[0017] Thirdly, the present invention provides an electronic device comprising: a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions being executed by the processor to implement the steps of the lunar surface user positioning method as described in the first aspect.

[0018] Fourthly, the present invention provides a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the lunar surface user positioning method as described in the first aspect.

[0019] Compared with existing technologies, this invention has the following advantages: First, the user equipment located on the lunar surface transmits electromagnetic wave signals to the lunar satellite, then receives the electromagnetic wave signals reflected back by the satellite, and records the round-trip time t between the user equipment and the satellite. Based on the round-trip time t, the distance d between the user equipment and the satellite is calculated, where d = c·t / 2, and c is the speed of light. Finally, after obtaining the distances between at least three satellites and the user equipment, the user coordinates on the lunar surface are calculated by combining the coordinates of each satellite and using the tri-sphere rendezvous positioning principle. This achieves accurate positioning in the lunar environment, with lower costs and simplified lunar satellite payload configuration. Attached Figure Description

[0020] The accompanying drawings are included to provide a further understanding of this application; they are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of this application. In the drawings:

[0021] Figure 1 This is a flowchart illustrating a method for locating users on the lunar surface according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of a positioning device for users on the lunar surface according to an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0025] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0026] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0027] Flowcharts are used in this application to illustrate the operations performed by the system according to embodiments of this application. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, various steps can be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more steps may be removed from these processes.

[0028] Figure 1 This is a flowchart illustrating a method for locating users on the lunar surface according to an embodiment of the present invention. (Refer to...) Figure 1 As shown, method 100 includes: S110, a user device located on the lunar surface transmits an electromagnetic wave signal to a lunar satellite; S120, receives the electromagnetic wave signal reflected back by the satellite and records the round-trip time t between the user device and the satellite; S130, calculates the distance d between the user device and the satellite based on the round-trip time t, d = c·t / 2, where c is the speed of light; S140, after obtaining the distances between at least three satellites and the user device, calculates the user coordinates on the lunar surface using the tri-sphere rendezvous positioning principle, in conjunction with the coordinates of each satellite.

[0029] In this embodiment, the lunar satellites possess known ephemeris data, i.e., their precise orbital data. User equipment located on the lunar surface acts as a transmitter, sending electromagnetic signals, such as radio / laser signals, to the orbiting satellites. By employing radio / laser ranging and velocimetry techniques, the distance and velocity information between the satellite carrying precise orbital data and the lunar surface equipment are analyzed, thereby calculating the user's accurate position on the lunar surface. It is evident that although this embodiment applies the tri-sphere rendezvous positioning principle, due to the unique characteristics of lunar surface user positioning, this embodiment places the signal transmitting device within the lunar surface user equipment. This is partly because there are currently relatively few users (or equipment) on the lunar surface, and partly because it reduces the number of lunar satellites required, lightens the satellite load, and improves the payload utilization rate of the lunar satellites.

[0030] In one example, the satellites are those within a constructed space segment, which consists of 4 NRHO orbit satellites and 24 ELFO orbit satellites. This lunar satellite configuration achieves 100% quadruple coverage of the entire lunar surface, with each satellite carrying precise ephemeris data, i.e., their exact position in orbit (x...). i ,y i ,z i (Known)

[0031] The NRHO orbit is a Near Rectilinear Halo Orbit, a subset of halo orbits in the Earth-Moon system, characterized by its proximity to the Moon and nearly stable behavior. The NRHO orbit combines the advantages of a low lunar orbit (surface access) and a distant retrograde orbit (fuel efficiency). The NRHO orbit also provides scientists with opportunities to conduct radiation experiments in deep space, contributing to a deeper understanding of the potential impacts of space weather on personnel and instruments.

[0032] The ELFO orbit is an elliptical lunar frozen orbit with a nearly constant eccentricity and a nearly constant periodic orientation. Satellites in this orbit experience relatively stable motion, requiring minimal thrust to maintain their position. In a frozen orbit, the satellite's average velocity matches the celestial body's rotation speed, maintaining a relatively fixed position relative to the body's surface. The ELFO orbit is considered for constructing lunar navigation constellations to ensure real-time, high-precision positioning for lunar missions.

[0033] In one example, the electromagnetic wave signal is a laser signal. The laser beam is concentrated, resulting in a high power density on the receiving terminal, allowing the receiver to be made smaller and lighter. The laser beam is also very narrow, making it less likely to be intercepted.

[0034] In one example, the user equipment is equipped with a high-precision clock and a laser ranging device, while the satellite is equipped with a laser corner reflector. With this configuration, the user equipment on the lunar surface emits a laser beam directed at the laser corner reflector in the space segment. After the laser beam hits the corner reflector on the satellite, it is precisely reflected back to the user equipment. Subsequently, the user equipment receives the reflected laser beam and records the total round-trip time t.

[0035] In one example, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle. If three satellites are used for positioning, the user coordinates on the lunar surface can be calculated using the following system of equations:

[0036]

[0037] In the formula, (x1,y1) are the coordinates of the first satellite, (x2,y2) are the coordinates of the second satellite, (x3,y3) are the coordinates of the third satellite, (x,y,z) are the coordinates of the user on the lunar surface, and t1, t2, and t3 are the round-trip times recorded by the three satellites, respectively.

[0038] In one example, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle. If four or more satellites are used for positioning, the numerical solution satisfies the following:

[0039]

[0040] For example, the least squares method can be used to find the optimal coordinates (i.e., the optimal solution) by minimizing the squared difference of distances. In the above formula, n represents n satellites, n≥4, and (x,y,z) are the coordinates of the user on the lunar surface, (x...y...z ... i ,y i ,z i ) represents the coordinates of the i-th satellite.

[0041] In one example, method 100 also includes using Kalman filtering to correct the calculated coordinates of the lunar surface user.

[0042] The practical application of method 100 in this embodiment may be affected by factors such as lunar surface reflection characteristics, equipment time accuracy, and satellite orbit errors. Therefore, filtering techniques can be used to optimize and correct coordinate positions, thereby reducing errors and improving the reliability of positioning results.

[0043] The Kalman filter can estimate the state of a dynamic system in the presence of noise and uncertainty. Its core idea is to use the linear system's state equations and the system's input-output observations to make an optimal estimate of the system state. The Kalman filter works based on two key steps: prediction and update. In the prediction phase, the filter uses the estimate of the previous state to predict the current state. In the update phase, the filter uses the observations of the current state to optimize the prediction, thereby obtaining a more accurate new estimate.

[0044] In the lunar environment, Kalman filtering uses pseudorange and pseudorange change rate provided by lunar navigation satellites as observations, combined with a dynamic model that integrates information from microwave direction finding, optical measurements, inertial navigation, and atomic clocks from the receiver, to predict the state. The error covariance matrix is ​​dynamically adjusted based on the deviation between the observed and predicted values. Through a recursive prediction and update process, Kalman filtering effectively suppresses the impact of noise on positioning accuracy, overcomes the lack of lunar surface geographic information and weak infrastructure, and can improve positioning accuracy in the complex lunar environment.

[0045] In applying the method of this embodiment, the positioning system is configured with a user segment and a space segment. The user segment equipment is deployed on the lunar surface and has the capability to transmit signals to the space segment satellites. The space segment comprises at least three microsatellites carrying precise ephemeris data, deployed in specific lunar orbits to achieve full coverage of the lunar surface. The user equipment on the lunar surface transmits signals at specific frequencies to the satellites in orbit. These space segment satellites possess known and precise orbital data. Using ranging and velocity measurement technologies such as radio, combined with the precise orbital data of the satellites and the ranging information from the lunar surface transmitters, the user's position on the lunar surface can be accurately calculated.

[0046] Compared to traditional satellite navigation systems, the method in this embodiment reduces the complexity requirements for satellites. The space segment satellites primarily serve as fixed reference points with known locations, eliminating the need to broadcast conventional navigation signals. The user terminal can complete its positioning calculation simply by performing a one-way distance measurement with the space segment. This method has a wide range of applications, including positioning and navigation for lunar rovers, mining operations, scientific research, and other lunar surface activities.

[0047] Another embodiment of the present invention provides a positioning device for users on the lunar surface, with reference to... Figure 2 As shown, the device 200 includes: a signal transmitting module 201, used to enable a user device located on the lunar surface to transmit electromagnetic wave signals to a lunar satellite; a signal receiving module 202, used to receive electromagnetic wave signals reflected back by the satellite and record the round-trip time t between the user device and the satellite; a first calculation module 203, used to calculate the distance d between the user device and the satellite based on the round-trip time t, where d = c·t / 2, and c is the speed of light; and a second calculation module 204, used to calculate the user coordinates on the lunar surface by combining the coordinates of each satellite with the coordinates of at least three satellites after obtaining the distances between the user device and the satellite, using the principle of tri-sphere rendezvous positioning.

[0048] In one example, the satellites are satellites within a constructed space segment, which consists of 4 NRHO orbit satellites and 24 ELFO orbit satellites.

[0049] In one example, the electromagnetic wave signal is a laser signal.

[0050] In one example, the user equipment is equipped with a high-precision clock and a laser ranging device, while the satellite is equipped with a laser corner reflector.

[0051] In one example, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle. If three satellites are used for positioning, the user coordinates on the lunar surface can be calculated using the following system of equations:

[0052]

[0053] In the formula, (x1,y1) are the coordinates of the first satellite, (x2,y2) are the coordinates of the second satellite, (x3,y3) are the coordinates of the third satellite, (x,y,z) are the coordinates of the user on the lunar surface, and t1, t2, and t3 are the round-trip times recorded by the three satellites, respectively.

[0054] In one example, the user coordinates on the lunar surface can be calculated using the tri-sphere rendezvous positioning principle. If four or more satellites are used for positioning, the user's coordinates (x, y, z) on the lunar surface can be solved numerically using methods that satisfy:

[0055]

[0056] In the formula, n represents n satellites, n≥4, (x i ,y i ,z i Let d be the coordinates of the i-th satellite. i Let be the distance between the i-th satellite and the user equipment.

[0057] In one example, the device 200 also includes a correction module for correcting the calculated coordinates of the lunar surface user using Kalman filtering techniques.

[0058] Details of other operations performed by each module in this embodiment can be found in the foregoing embodiments, and will not be elaborated here.

[0059] In this embodiment, the positioning device for users on the lunar surface first transmits electromagnetic wave signals to the lunar satellite from the user equipment located on the lunar surface. Then, it receives the electromagnetic wave signals reflected back by the satellite and records the round-trip time t between the user equipment and the satellite. Based on the round-trip time t, the distance d between the user equipment and the satellite is calculated, where d = c·t / 2, and c is the speed of light. Finally, after obtaining the distances between the user equipment and at least three satellites, the coordinates of each satellite are combined with the coordinates of the satellites to calculate the user's coordinates on the lunar surface using the tri-sphere rendezvous positioning principle. This achieves accurate positioning in the lunar environment with low cost and simplifies the configuration of lunar satellite payloads.

[0060] The positioning device for a lunar surface user in this embodiment can be a device, or a component, integrated circuit, or chip in a terminal. The positioning device for a lunar surface user in this embodiment can be a device with an operating system. This operating system can be Android, iOS, or other possible operating systems; this embodiment does not specifically limit the specific operating system.

[0061] This application also provides an electronic device, including: a memory for storing programs or instructions executable by a processor; and a processor for executing the programs or instructions to implement the various processes of the above-described lunar surface user positioning method embodiments, and achieving the same technical effects. To avoid repetition, these will not be described again here.

[0062] Figure 3 This is a schematic diagram of an electronic device according to an embodiment of the present invention. The electronic device 300 may include an internal communication bus 301, a processor 302, a read-only memory (ROM) 303, a random access memory (RAM) 304, and a communication port 305. When applied to a personal computer, the electronic device 300 may also include a hard disk 306. The internal communication bus 301 enables data communication between components of the electronic device 300. The processor 302 can perform judgments and issue prompts. In some embodiments, the processor 302 may consist of one or more processors. The communication port 305 enables data communication between the electronic device 300 and external devices. In some embodiments, the electronic device 300 can send and receive information and data from a network through the communication port 305. The electronic device 300 may also include different forms of program storage units and data storage units, such as the hard disk 306, the read-only memory (ROM) 303, and the random access memory (RAM) 304, capable of storing various data files used for computer processing and / or communication, as well as possible programs or instructions executed by the processor 302. The result processed by processor 302 is transmitted to the user equipment through communication port 305 and displayed on the user interface.

[0063] The above-described method for locating lunar surface users can be implemented as a computer program, stored in hard disk 306, and recorded in processor 302 for execution, in order to implement any of the lunar surface user location methods in this application.

[0064] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described lunar surface user positioning method embodiment and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0065] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0066] Although this application has been described with reference to specific embodiments, those skilled in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, any changes or modifications to the above embodiments within the essential spirit of this application will fall within the scope of the claims of this application.

Claims

1. A method for locating users on the lunar surface, characterized in that, include: User equipment located on the lunar surface transmits electromagnetic signals to lunar satellites; The satellites mentioned are satellites within the constructed space segment, which consists of 4 NRHO orbit satellites and 24 ELFO orbit satellites; Receive the electromagnetic wave signal reflected back by the satellite and record the round-trip time t between the user equipment and the satellite. Based on the round-trip time t, the distance d between the user equipment and the satellite is calculated, where d = c·t / 2, and c is the speed of light; After obtaining the distances between at least three satellites and the user equipment, the user's coordinates on the lunar surface are calculated using the tri-sphere rendezvous positioning principle, in conjunction with the coordinates of each satellite. If four or more satellites are used for positioning, the coordinates (x, y, z) of the user on the lunar surface can be solved numerically, satisfying the following: In the formula, n represents n satellites, n≥4, (x i ,y i ,z i Let d be the coordinates of the i-th satellite. i Let be the distance between the i-th satellite and the user equipment.

2. The method for locating users on the lunar surface as described in claim 1, characterized in that, The electromagnetic wave signal is a laser signal.

3. The method for locating users on the lunar surface as described in claim 2, characterized in that, The user equipment is equipped with a high-precision clock and a laser ranging device, and the satellite is equipped with a laser corner reflector.

4. The method for locating users on the lunar surface as described in claim 1, characterized in that, Also includes: The calculated coordinates of users on the lunar surface were corrected using Kalman filtering.

5. A positioning device for a user on the lunar surface, characterized in that, include: The signal transmission module is used to enable user equipment located on the lunar surface to transmit electromagnetic wave signals to the lunar satellite; The satellites mentioned are satellites within the constructed space segment, which consists of 4 NRHO orbit satellites and 24 ELFO orbit satellites; The signal receiving module is used to receive electromagnetic wave signals reflected back by the satellite and record the round-trip time t between the user equipment and the satellite. The first calculation module is used to calculate the distance d between the user equipment and the satellite based on the round-trip time t, where d = c·t / 2, and c is the speed of light; The second calculation module is used to calculate the user's coordinates on the lunar surface by combining the coordinates of each of the satellites with the principle of tri-sphere rendezvous positioning after obtaining the distances between at least three satellites and the user equipment. If four or more satellites are used for positioning, the coordinates (x, y, z) of the user on the lunar surface can be solved numerically, satisfying the following: In the formula, n represents n satellites, n≥4, (x i ,y i ,z i Let d be the coordinates of the i-th satellite. i Let be the distance between the i-th satellite and the user equipment.

6. An electronic device, characterized in that, include: A processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the lunar surface user positioning method as described in any one of claims 1-4.

7. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the lunar surface user positioning method as described in any one of claims 1-4.

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