A lunar navigation and remote sensing satellite formation system and collaborative working method

Abstract

The present invention provides a lunar communication, navigation, and remote sensing satellite formation system and collaborative working method. The system is deployed in lunar orbit and provides communication, navigation, and remote sensing services to lunar users through collaborative work between satellites within the system and cooperation between the satellite formation system and the ground Ka tracking and control station. The lunar communication, navigation, and remote sensing satellite formation system includes a master satellite and a slave satellite. The master satellite includes a satellite-to-ground high-speed tracking and control unit, an intersatellite link unit, a communication payload, a navigation payload, an ultra-stable time and frequency unit, and an integrated electronics unit; the slave satellite includes a tracking and control unit, an intersatellite link unit, a communication payload, a navigation payload, a remote sensing payload, and an integrated electronics unit. By setting a lunar orbit, configuring communication, navigation, and remote sensing functions, and coordinating satellites within the system, the present invention provides comprehensive communication, navigation, and remote sensing services to lunar users in lunar space, where signals from Earth navigation systems are not available and signals from ground tracking and control systems have limited coverage.

Description

Technical Field

[0001] The present invention relates to the field of deep space exploration technology, and in particular to a lunar communication, navigation and remote sensing satellite formation system and a collaborative working method. Background Art

[0002] In recent years, lunar exploration has flourished. Major space-faring nations have proposed and are gradually implementing lunar exploration mission plans. Communications and navigation support for lunar probes is a crucial prerequisite for the normal operation of lunar exploration activities. Both unmanned lunar exploration and manned lunar landings also require detailed lunar remote sensing data.

[0003] In current lunar exploration activities, the communication services of the probe are basically provided by ground tracking and control stations. In areas that are difficult to cover by ground tracking and control stations, such as the far side of the moon and the poles, relay communication support is provided by lunar orbit relay communication satellites. The navigation services of the probe are basically provided by the ground tracking and control stations, which determine the orbit of the probe and then add the orbit and timing to the probe. Remote sensing data is mainly realized by carrying remote sensing payloads on the lunar probe and transmitting the data to the ground tracking and control station.

[0004] It can be seen that current lunar communication, navigation, and remote sensing services rely heavily on ground-based tracking and control stations or dedicated satellites, resulting in limited service coverage and the number of users served. With the increasing number of lunar probes and the in-depth exploration of the lunar far side and polar regions, relying solely on ground-based tracking and control stations can no longer meet the communication and navigation support needs of future lunar exploration. Therefore, it is urgent to develop a lunar communication, navigation, and remote sensing system to provide full-time, global service support for lunar exploration activities. Compared to a single or a small number of single-function satellites, forming a formation of multiple satellites in lunar orbit, where each satellite in the formation works together and interconnects to achieve signal coverage of key lunar regions and jointly accomplish communication, navigation, and remote sensing tasks, is a low-cost, high-performance, highly reliable, and highly adaptable technology approach.

[0005] There are many problems with the existing lunar communication, navigation and remote sensing services. For example, Chinese patent application CN202410296750.1 proposes a dual-satellite detection method for the lunar very low orbit. The method consists of two satellites, both of which are located in the same circular orbit around the moon. They carry a specific environmental element detection payload to obtain the physical field characteristics of the near-lunar space and depict the scene of the entry and exit of materials in the near-lunar space, but it does not involve communication and navigation functions. Chinese patent application CN115955266A proposes a method for the linkage of integrated communication, navigation and remote sensing satellites, constellations and their functions. Multiple integrated communication, navigation and remote sensing satellites transmit information through inter-satellite transmission equipment and form a constellation. The constellation and the ground segment form a space-ground integrated network. However, the satellites are arranged in Earth orbit and cannot provide relay communication, navigation and remote sensing services for lunar users. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a lunar communication, navigation and remote sensing satellite formation system and a collaborative working method. By setting the lunar orbit, configuring the communication, navigation and remote sensing functions, and coordinating the satellites within the system, comprehensive communication, navigation and remote sensing services are provided to lunar users in lunar space where the Earth navigation system signals cannot cover and the ground measurement and control system signals have limited coverage.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A lunar communication, navigation, and remote sensing satellite formation system deployed in lunar orbit provides communication, navigation, and remote sensing services to lunar users through collaborative work between satellites within the system and cooperation between the satellite formation system and the ground Ka tracking and control station.

[0009] The lunar communication, navigation and remote sensing satellite formation system includes a master satellite and a slave satellite. The master satellite contains a satellite-to-ground high-speed measurement and control unit, an inter-satellite link unit, a communication payload, a navigation payload, an ultra-stable time and frequency unit, and an integrated electronic unit; the slave satellite contains a measurement and control unit, an inter-satellite link unit, a communication payload, a navigation payload, a remote sensing payload, and an integrated electronic unit.

[0010] The satellite-to-ground high-speed tracking and control unit establishes a Ka-band two-way satellite-to-ground high-speed link with the ground Ka tracking and control station, which is used for two-way high-speed communication between the ground Ka tracking and control station and the main satellite and for orbit determination of the main satellite;

[0011] The intersatellite link unit is used to establish intersatellite links between lunar navigation and remote sensing satellites for intersatellite communication, ranging and time synchronization;

[0012] The communication payload establishes a two-way satellite-moon link with lunar users;

[0013] The navigation payload can send navigation signals to lunar users, providing navigation, positioning and timing services;

[0014] The ultra-stable time and frequency unit uses the onboard atomic clock to provide highly stable time and frequency reference signals for the main satellite;

[0015] The integrated electronic unit is the business management, data storage and processing unit of the lunar navigation and remote sensing satellite;

[0016] The measurement and control unit is used by the ground measurement and control station to measure and control the slave satellite;

[0017] The remote sensing payload has the capability of remote sensing imaging of the moon.

[0018] Furthermore, the satellite-to-ground high-speed measurement and control unit includes a high-speed communication machine, a Ka low-gain antenna and a Ka high-gain antenna. The Ka low-gain antenna is selected for conventional measurement and control, and the Ka high-gain antenna is selected when high-speed uplink and downlink are required. The signal modulation method is a GMSK+PN system that can realize the integration of high-speed communication and ranging. The GMSK signal is used to transmit high-speed data, and the PN signal is used to regenerate pseudo-code ranging.

[0019] Furthermore, the inter-satellite link unit includes a Ka phased array antenna and an inter-satellite measurement and communication machine. The Ka phased array antenna quickly establishes an inter-satellite bidirectional link through flexible beam scanning. The inter-satellite measurement and communication machine performs inter-satellite communication, inter-satellite ranging and time synchronization. The signal modulation mode is GMSK+PN. The GMSK signal is used for inter-satellite high-speed data transmission, and the PN signal is used for inter-satellite ranging and time synchronization through a two-way one-way pseudo-range measurement method.

[0020] Furthermore, the communication payload covers at least one of the X-band and the Ka-band, and uses a multi-beam antenna to achieve simultaneous communication with multiple lunar users.

[0021] Furthermore, the navigation payload includes a navigation transmitting antenna and a navigation transmitter, and the navigation signal includes a navigation message, a pseudo-random code and a carrier signal.

[0022] Furthermore, after receiving the ground timing signal, the ultra-stable time and frequency unit outputs a stable clock signal to the integrated electronic unit, which then outputs it to other equipment and payloads on the satellite to ensure the uniformity of the time reference on the satellite.

[0023] Furthermore, the ultra-stable time-frequency unit provides a frequency reference signal with high stability and accuracy for other equipment and payloads on board the satellite.

[0024] Furthermore, the integrated electronic unit schedules the satellite's mission execution and converts on-board data into data required for user services.

[0025] Furthermore, the measurement and control unit includes a measurement and control transponder and a measurement and control antenna, which receives remote control signals from a ground measurement and control station and sends onboard telemetry data to the ground measurement and control station;

[0026] Furthermore, the remote sensing payload includes at least one of an optical remote sensing payload and a radar remote sensing payload to carry out a detailed survey of the moon.

[0027] The present invention also provides a collaborative working method of a lunar communication, navigation and remote sensing satellite formation system, comprising:

[0028] 1) The system uses ground-based orbit determination and timing combined with intersatellite link ranging and time synchronization to perform satellite-satellite-ground multi-source precise orbit determination, enabling the transmission of time and space reference information within the system, improving the system's own time and space reference accuracy and autonomous operation capabilities;

[0029] 2) Lunar communication, navigation and remote sensing satellites provide communication services to multiple lunar users within the beam coverage area through the moon-satellite link;

[0030] 3) Multiple lunar communication, navigation and remote sensing satellites establish communication links between two distant lunar users through satellite-moon links and inter-satellite links to provide communication services;

[0031] 4) Lunar communication, navigation and remote sensing satellites provide high-speed relay communication services to lunar users through satellite-moon links and satellite-to-ground high-speed links;

[0032] 5) Multiple lunar communication, navigation and remote sensing satellites provide uninterrupted high-speed relay communication services to lunar users through satellite-moon links, inter-satellite links, and satellite-to-ground high-speed links;

[0033] 6) Four or more lunar communication, navigation, and remote sensing satellites transmit navigation signals to lunar users. After receiving the navigation signals, lunar users can locate and navigate their own positions based on the principle of multi-sphere rendezvous. Lunar communication, navigation, and remote sensing satellites equipped with ultra-stable time and frequency units can also provide timing services to users.

[0034] 7) After obtaining lunar exploration data through remote sensing payloads, lunar navigation and remote sensing satellites provide remote sensing data to lunar users through satellite-moon links and inter-satellite links, or send remote sensing data to the ground through inter-satellite links and satellite-to-ground high-speed links.

[0035] Beneficial effects:

[0036] By setting up a lunar orbit, configuring communication, navigation, and remote sensing functions, and coordinating satellites within the system, the present invention provides comprehensive communication, navigation, and remote sensing services to lunar users in lunar space, where Earth navigation system signals are unable to reach and ground measurement and control system signals have limited coverage. These services include:

[0037] (1) All satellites in the formation have the ability to establish inter-satellite links. The rapid transmission of information within the formation improves the response speed, and the ground station can quickly measure and control the satellites in the formation;

[0038] (2) Through the coordinated satellite-to-moon, satellite-to-ground, and inter-satellite communication functions of multiple satellites, rapid communication between lunar users and between lunar users and the ground is achieved;

[0039] (3) The satellite is equipped with an ultra-stable time and frequency unit. Through the coordination of the inter-satellite measurement function and navigation function of multiple satellites, the transmission of time and space references within the system is realized, providing better navigation, positioning and timing services for lunar users.

[0040] (4) Provide rapid remote sensing services to lunar users through the coordination of remote sensing and communication functions of multiple satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic diagram of the structure and functions of the lunar navigation and remote sensing satellite formation system of the present invention;

[0042] Figure 2 This is a schematic diagram of time and space reference transmission of the lunar navigation and remote satellite formation system of the present invention;

[0043] Figure 3 This is a schematic diagram of the communication services of the lunar navigation and remote sensing satellite formation system of the present invention;

[0044] Figure 4 This is a schematic diagram of the relay communication service of the lunar navigation and remote sensing satellite formation system of the present invention;

[0045] Figure 5 This is a navigation service diagram of the lunar navigation and remote sensing satellite formation system of the present invention;

[0046] Figure 6 It is a schematic diagram of remote sensing services of the lunar navigation and remote sensing satellite formation system of the present invention. DETAILED DESCRIPTION

[0047] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0048] The lunar communication, navigation and remote sensing satellite formation system is deployed in lunar orbit. Through the collaborative work between satellites within the system and the cooperation between the satellite formation system and the ground measurement and control system, it provides communication, navigation and remote sensing (communication, navigation and remote sensing) services to lunar users such as lunar surface and lunar orbit probes.

[0049] The lunar navigation and remote sensing satellite formation system consists of a master satellite and a slave satellite. The master satellite contains a high-speed satellite-to-ground tracking and control unit, an intersatellite link unit, a communications payload, a navigation payload, an ultra-stable time and frequency unit, and an integrated electronics unit; the slave satellite contains a tracking and control unit, an intersatellite link unit, a communications payload, a navigation payload, a remote sensing payload, and an integrated electronics unit.

[0050] The satellite-to-ground high-speed measurement and control unit establishes a Ka-band, bidirectional, high-speed satellite-to-ground link with the ground-based Ka measurement and control station, enabling bidirectional high-speed communication between the ground-based Ka measurement and control station and the primary satellite, as well as orbit determination of the primary satellite. The satellite-to-ground high-speed measurement and control unit includes a high-speed communication device, a Ka low-gain antenna, and a Ka high-gain antenna. The Ka low-gain antenna is selected for routine measurement and control, while the Ka high-gain antenna is selected for high-speed uplink and downlink. The signal modulation scheme uses the GMSK+PN system, which integrates high-speed communication and ranging. The GMSK signal is used for high-speed data transmission, and the PN signal is used for regenerated pseudo-code ranging.

[0051] The intersatellite link unit is used to establish an intersatellite link between lunar navigation and remote sensing satellites to perform intersatellite communication, ranging and time synchronization. The intersatellite link unit includes a Ka phased array antenna and an intersatellite measurement and communication machine. The Ka phased array antenna quickly establishes an intersatellite bidirectional link through flexible beam scanning. The intersatellite measurement and communication machine performs intersatellite communication, intersatellite ranging and time synchronization. The signal modulation mode is GMSK+PN. The GMSK signal is used for high-speed intersatellite data transmission. The PN signal is used for intersatellite ranging and time synchronization through a two-way one-way pseudo-range measurement method.

[0052] The communication payload establishes a two-way satellite-moon link with lunar users; the communication payload covers at least one of the X-band and Ka-band frequencies, and uses a multi-beam antenna to achieve simultaneous communication with multiple lunar users;

[0053] The navigation payload can send navigation signals to lunar users to provide navigation, positioning and timing services; the navigation payload includes a navigation transmitting antenna and a navigation transmitter, and the navigation signal includes a navigation message, a pseudo-random code and a carrier signal;

[0054] The ultra-stable time and frequency unit uses the onboard atomic clock to provide a highly stable time and frequency reference signal for the host satellite. After receiving the ground timing signal, the ultra-stable time and frequency unit outputs a stable clock signal to the integrated electronic unit, which then outputs the signal to other devices and payloads on the satellite to ensure the uniformity of the onboard time reference. The ultra-stable time and frequency unit provides a highly stable and accurate frequency reference signal to other devices and payloads on the satellite.

[0055] The integrated electronic unit is the business management, data storage and processing unit of the lunar communication, navigation and remote sensing satellite, which schedules the satellite's mission execution and converts on-board data into data required for user services;

[0056] The TT&C unit includes a TT&C transponder and a TT&C antenna, which receives remote control signals from the ground TT&C station and sends onboard telemetry data to the ground TT&C station.

[0057] The remote sensing payload has the function of lunar remote sensing, including at least one of optical remote sensing payload and radar remote sensing payload, to carry out detailed survey of the moon.

[0058] In order to provide communication, navigation and remote sensing services for lunar users, the collaborative working method of the lunar communication, navigation and remote sensing satellite formation system of the present invention includes:

[0059] 1) The system uses ground-based orbit determination and timing combined with intersatellite link ranging and time synchronization to perform satellite-satellite-ground multi-source precise orbit determination, enabling the transmission of time and space reference information within the system, improving the system's own time and space reference accuracy and autonomous operation capabilities;

[0060] 2) Lunar communication, navigation and remote sensing satellites provide communication services to multiple lunar users within the beam coverage area through the moon-satellite link;

[0061] 3) Multiple lunar communication, navigation and remote sensing satellites establish communication links between two distant lunar users through satellite-moon links and inter-satellite links to provide communication services;

[0062] 4) Lunar communication, navigation and remote sensing satellites provide high-speed relay communication services to lunar users through satellite-moon links and satellite-to-ground high-speed links;

[0063] 5) Multiple lunar communication, navigation and remote sensing satellites provide uninterrupted high-speed relay communication services to lunar users through satellite-moon links, inter-satellite links, and satellite-to-ground high-speed links;

[0064] 6) Four or more lunar communication, navigation, and remote sensing satellites transmit navigation signals to lunar users. After receiving the navigation signals, lunar users can locate and navigate their own positions based on the principle of multi-sphere rendezvous. Lunar communication, navigation, and remote sensing satellites equipped with ultra-stable time and frequency units can also provide timing services to users.

[0065] 7) After obtaining lunar exploration data through remote sensing payloads, lunar navigation and remote sensing satellites provide remote sensing data to lunar users through satellite-moon links and inter-satellite links, or send remote sensing data to the ground through inter-satellite links and satellite-to-ground high-speed links.

[0066] Example:

[0067] The lunar navigation and remote sensing satellite formation system consists of multiple lunar navigation and remote sensing satellites, including both master and slave satellites. The lunar orbit, number of satellites deployed, and type of satellites are determined by the service coverage requirements for lunar users. For example, circumlunar highly elliptical frozen orbits (ELFO) and circumlunar circular orbits (CLO) can be selected. ELFO defines two orbital planes, each with M (≥2) master satellites deployed. CLO defines three orbital planes at the same altitude, each with N (≥1) master satellites and P (≥8) slave satellites deployed. The CLO orbital altitude is less than 1500km, ensuring communication speed and remote sensing data quality with users on the lunar surface.

[0068] like Figure 1 As shown, the main satellite includes a satellite-to-ground high-speed measurement and control unit, an intersatellite link unit, a communication payload, a navigation payload, an ultra-stable time and frequency unit, and an integrated electronic unit;

[0069] The satellite-to-ground high-speed measurement and control unit establishes a satellite-to-ground high-speed link with the ground Ka measurement and control station. It receives telemetry data or downlink data from the integrated electronic unit, converts it into Ka-band signals, and sends them to the ground Ka measurement and control station. It also receives remote control commands or uplink data from the ground Ka measurement and control station and sends them to the integrated electronic unit for processing.

[0070] The intersatellite link unit generates a PN code for ranging, performs GMSK modulation on it together with the baseband communication data and satellite time sent by the integrated electronics, and then sends it to other satellites in the formation. It receives signals sent by other satellites in the formation, calculates the inter-satellite distance and time difference, decodes the communication data, and sends the calculation results and communication data to the integrated electronics unit.

[0071] The communication payload establishes a communication link with the lunar user and sends communication data to the integrated electronic unit according to the user's communication needs.

[0072] The navigation payload sends navigation signals to lunar users, providing navigation, positioning and timing services. The navigation signals include navigation messages, pseudo-random codes and carrier signals.

[0073] The integrated electronic unit is bidirectionally connected to the satellite-to-ground high-speed measurement and control unit, intersatellite link unit, communication payload, navigation payload, and remote sensing payload for task scheduling, data storage, and interaction.

[0074] The ultra-stable time and frequency unit provides frequency reference signals for the satellite-to-ground high-speed measurement and control unit, intersatellite link unit, communication payload, navigation payload, and remote sensing payload. The ultra-stable time and frequency unit undergoes frequency calibration via the satellite-to-ground high-speed measurement and control unit. The satellite-to-ground high-speed measurement and control unit receives the frequency reference signal from the ultra-stable time and frequency unit, generates a single-carrier beacon signal in the Ka band, and transmits it to the ground-based Ka measurement and control station. The ground-based Ka measurement and control station then calculates the frequency deviation, thereby calibrating the ultra-stable time and frequency unit.

[0075] After receiving the ground timing signal through the satellite-to-ground high-speed measurement and control unit, the ultra-stable time and frequency unit outputs a stable clock signal to the integrated electronic unit, which then outputs it to other equipment and payloads on the satellite to ensure the uniformity of the onboard time reference.

[0076] The slave satellite includes a measurement and control unit, an inter-satellite link unit, a communication payload, a navigation payload, a remote sensing payload, and an integrated electronic unit. The slave satellite realizes the measurement and control function through the measurement and control unit. The measurement and control unit uses the S band or X band and adopts the USB or UXB measurement and control system to establish a measurement and control link with the ground measurement and control station.

[0077] The intersatellite link unit and communication payload functions of the slave satellite are basically the same as those of the master satellite, except that they do not use the reference frequency provided by the ultra-stable time and frequency unit.

[0078] The remote sensing payload sends remote sensing data to the integrated electronic unit based on optical or microwave imaging of the moon.

[0079] like Figure 2As shown, a high-speed satellite-to-ground link is established between the master satellite and the ground-based Ka tracking and control station, and inter-satellite links are established between the satellites in the formation. Through inter-satellite communication, the ground-based Ka tracking and control station can track and control other satellites in the formation that are not in the tracking and control arc, thereby improving the formation's responsiveness and collaborative capabilities. The ground-based Ka tracking and control station determines the orbit and provides timing for the master satellite. The master satellite uses an ultra-stable time and frequency unit to calibrate and maintain time. Inter-satellite ranging and time synchronization are performed between the satellites in the formation. This serves as a supplementary observation during the ground-based orbit determination process, improving the accuracy of satellite orbit determination. It also enables inter-satellite transmission of time and space references, improving the formation's own reference accuracy and autonomous management capabilities.

[0080] The system's communication services include Figure 3 As shown, the satellite supports low-speed communications for multiple lunar users (≥3) within its beam range, high-speed communications for a single lunar user, and high-speed communications between multiple lunar users at greater distances, outside the beam range of a single satellite. The intersatellite and satellite-moon links provide collaborative communications services with full, all-month coverage.

[0081] The system's relay communication services include Figure 4 As shown in the figure, the main satellite forwards the measurement and control communication data between the lunar users and the ground Ka measurement and control station through the satellite-to-ground high-speed link and the satellite-to-moon link, or the satellite-to-ground high-speed link, the inter-satellite link and the satellite-to-moon link, providing lunar users with reliable relay services all the time and all month long.

[0082] The system's navigation services include Figure 5 As shown, the remote sensing payloads of four or more satellites send navigation signals to lunar users. After receiving the navigation signals, the lunar users can realize their own positioning and navigation based on the multi-sphere rendezvous principle. The master satellite can provide high-precision timing services to users, and the slave satellite can provide timing services to users.

[0083] The system's remote sensing services include Figure 6 As shown, the remote sensing payload of the satellite performs optical or microwave imaging of the moon according to the instructions of the integrated electronic unit, stores the data in the integrated electronic unit, and sends the data to the intersatellite link unit or communication payload as needed, and further sends it to the lunar user or the ground. The coordination of communication and remote sensing functions realizes rapid remote sensing services.

Claims

1. A lunar navigation and remote sensing satellite formation system, characterized in that: Deployed in lunar orbit, it provides communication, navigation, and remote sensing services to lunar users through collaborative work between satellites within the system, the satellite formation system, and the Ka tracking and control station on the ground. The lunar communication, navigation and remote sensing satellite formation system includes a master satellite and a slave satellite. The master satellite contains a satellite-to-ground high-speed measurement and control unit, an inter-satellite link unit, a communication payload, a navigation payload, an ultra-stable time and frequency unit, and an integrated electronic unit; the slave satellite contains a measurement and control unit, an inter-satellite link unit, a communication payload, a navigation payload, a remote sensing payload, and an integrated electronic unit. The satellite-to-ground high-speed tracking and control unit establishes a Ka-band two-way satellite-to-ground high-speed link with the ground Ka tracking and control station, which is used for two-way high-speed communication between the ground Ka tracking and control station and the main satellite and for orbit determination of the main satellite; The intersatellite link unit is used to establish intersatellite links between lunar navigation and remote sensing satellites for intersatellite communication, ranging and time synchronization; The communication payload establishes a two-way satellite-moon link with lunar users; The navigation payload can send navigation signals to lunar users, providing navigation, positioning and timing services; The ultra-stable time and frequency unit uses the onboard atomic clock to provide highly stable time and frequency reference signals for the main satellite; The integrated electronic unit is the business management, data storage and processing unit of the lunar navigation and remote sensing satellite; The measurement and control unit is used by the ground measurement and control station to measure and control the slave satellite; The remote sensing payload has the capability of remote sensing and imaging of the moon; The satellite-to-ground high-speed measurement and control unit includes a high-speed communication machine, a Ka low-gain antenna and a Ka high-gain antenna; By setting up the lunar orbit, configuring communication, navigation and remote sensing functions, and coordinating satellites within the system, comprehensive communication, navigation and remote sensing services are provided to lunar users in lunar space where the Earth's navigation system signals cannot reach and the ground measurement and control system signals have limited coverage.

2. A lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: A Ka low-gain antenna is selected for conventional measurement and control, and a Ka high-gain antenna is selected when high-speed uplink and downlink are required. The signal modulation method is the GMSK+PN system that can realize the integration of high-speed communication and ranging. The GMSK signal is used to transmit high-speed data, and the PN signal is used to regenerate pseudo-code ranging.

3. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The intersatellite link unit includes a Ka phased array antenna and an intersatellite measurement and communication machine. The Ka phased array antenna quickly establishes an intersatellite bidirectional link through flexible beam scanning. The intersatellite measurement and communication machine performs intersatellite communication, intersatellite ranging and time synchronization. The signal modulation mode is GMSK+PN. The GMSK signal is used for high-speed intersatellite data transmission, and the PN signal is used for intersatellite ranging and time synchronization through a two-way one-way pseudo-range measurement method.

4. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The communication payload covers at least one of the X-band and the Ka-band, and uses a multi-beam antenna to achieve simultaneous communication with multiple lunar users.

5. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The navigation payload includes a navigation transmitting antenna and a navigation transmitter, and the navigation signal includes a navigation message, a pseudo-random code and a carrier signal.

6. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: After receiving the ground timing signal, the ultra-stable time and frequency unit outputs a stable clock signal to the integrated electronic unit, which then outputs it to other equipment and payloads on the satellite to ensure the uniformity of the time reference on the satellite.

7. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The ultra-stable time-frequency unit provides a frequency reference signal with high stability and accuracy for other equipment and payloads on the satellite.

8. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The integrated electronic unit schedules the satellite's mission execution and converts on-board data into data required for user services.

9. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The measurement and control unit includes a measurement and control transponder and a measurement and control antenna, which receives remote control signals from the ground measurement and control station and sends onboard telemetry data to the ground measurement and control station.

10. The lunar navigation and remote sensing satellite formation system according to claim 1, characterized in that: The remote sensing payload includes at least one of an optical remote sensing payload and a radar remote sensing payload to carry out a detailed survey of the moon.

11. The collaborative working method of the lunar communication, navigation and remote sensing satellite formation system according to any one of claims 1 to 10, characterized in that: include: 1) The system uses ground-based orbit determination and timing combined with intersatellite link ranging and time synchronization to perform satellite-satellite-ground multi-source precise orbit determination, enabling the transmission of time and space reference information within the system, improving the system's own time and space reference accuracy and autonomous operation capabilities; 2) Lunar communication, navigation and remote sensing satellites provide communication services to multiple lunar users within the beam coverage area through the moon-satellite link; 3) Multiple lunar communication, navigation and remote sensing satellites establish communication links between two distant lunar users through satellite-moon links and inter-satellite links to provide communication services; 4) Lunar communication, navigation and remote sensing satellites provide high-speed relay communication services to lunar users through satellite-moon links and satellite-to-ground high-speed links; 5) Multiple lunar communication, navigation and remote sensing satellites provide uninterrupted high-speed relay communication services to lunar users through satellite-moon links, inter-satellite links, and satellite-to-ground high-speed links; 6) Four or more lunar communication, navigation, and remote sensing satellites transmit navigation signals to lunar users. After receiving the navigation signals, lunar users can locate and navigate their own positions based on the principle of multi-sphere rendezvous. Lunar communication, navigation, and remote sensing satellites equipped with ultra-stable time and frequency units can also provide timing services to users. 7) After obtaining lunar exploration data through remote sensing payloads, lunar navigation and remote sensing satellites provide remote sensing data to lunar users through satellite-moon links and inter-satellite links, or send remote sensing data to the ground through inter-satellite links and satellite-to-ground high-speed links.

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