Multi-layer Constellation

Abstract

To provide a multilayer constellation which takes advantages of an inclined orbit, an equatorial orbit and a polar orbit.SOLUTION: A multilayer constellation 1 forms a communication network where three satellite constellations 10-1, 10-2, 10-3 formed at different orbital altitudes straddle a plurality of orbital altitudes. The satellite constellations 10-1, 10-2, 10-3 each form an annular ring-shaped communication network 21 over the entire circumference of the earth by communication of each satellite between front and rear satellites in the advancing direction on the same orbital plane with both of the front and rear satellites in the advancing direction. At least one satellite constellation among the three satellite constellations is a hybrid constellation having a mission satellite 30M mounted with a mission device 31M which performs a specific mission as a satellite for communicating with both the front and rear satellites in the advancing direction.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to multi-layer constellations. [Background technology]

[0002] In the prior art, there is a technique for configuring a communication system using a satellite constellation (for example, Patent Document 1). When configuring a communication system using a satellite constellation, there is a problem that inclined orbits and equatorial orbits cannot provide service to high latitudes, including polar regions. Polar-orbiting satellites also have the problem that a large number of satellites are required to provide comprehensive service to low latitudes near the equator. Furthermore, there is a problem that a huge number of satellites is generally required to provide globally comprehensive service using low-orbit satellites. To solve these problems, it is desirable to provide a multi-layer constellation that takes advantage of the respective advantages of inclined, equatorial, and polar orbits. However, Patent Document 1 does not disclose a multi-layer constellation that takes advantage of the respective advantages of inclined, equatorial, and polar orbits. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US9647749B2 publication Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure aims to provide a multi-layer constellation that takes advantage of the advantages of inclined orbits, equatorial orbits, and polar orbits. [Means for solving the problem]

[0005] The multi-layer constellation according to the present disclosure forms a communication network spanning multiple orbital altitudes, with multiple satellite constellations formed at different orbital altitudes. Each satellite constellation of the plurality of satellite constellations comprises: A satellite sandwiched between two satellites in the same orbital plane communicates with both satellites in the front and rear of the satellite in the direction of travel, forming a circular communication network that covers the entire circumference of the Earth. At least one of the plurality of satellite constellations comprises: The hybrid constellation includes a mission satellite equipped with a mission device for carrying out a specific mission, as the satellite that communicates with both satellites ahead and behind it in the direction of travel. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide a multi-layer constellation that utilizes the advantages of inclined orbits, equatorial orbits, and polar orbits. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram of the first embodiment, showing a polar orbit 81, an inclined orbit 82, and an equatorial orbit 83 above the Earth 600. [Figure 2] FIG. 1 is a diagram of the first embodiment, showing a ring communication network 21. [Figure 3] FIG. 1 is a diagram of the first embodiment, showing four views of a communication satellite 30. [Figure 4] FIG. 1 is a diagram of the first embodiment, illustrating a circular communication network 21 on an inclined orbit 82. [Figure 5] FIG. 1 is a diagram of the first embodiment, showing an example in which a communication satellite 30 communicates with satellites flying in inclined orbits 82 adjacent to the left and right (east and west). [Figure 6] FIG. 1 is a diagram of the first embodiment, showing a mesh communication network 22. [Figure 7] FIG. 1 is a diagram of the first embodiment, showing a hybrid constellation in which a mission satellite 30M is added to the circular communication network 21 of the satellite constellation 11 in a polar orbit 81. [Figure 8] FIG. 1 is a diagram of the first embodiment, conceptually showing a multi-layer constellation 1. [Figure 9] FIG. 1 is a diagram of the first embodiment showing limb observations of a polar orbit 81, an inclined orbit 82, and an equatorial orbit 83. [Figure 10] FIG. 1 is a diagram of the first embodiment, showing a hardware configuration when a satellite 60 is a communication satellite 30. [Figure 11] FIG. 1 is a diagram of the first embodiment, showing the hardware configuration when the satellite 60 is a monitoring satellite. [Figure 12] FIG. 1 is a diagram of the first embodiment, showing the hardware configuration of a ground system 700. DETAILED DESCRIPTION OF THE INVENTION

[0008] In the description of the embodiments and drawings, the same elements and corresponding elements are denoted by the same reference numerals. The description of elements denoted by the same reference numerals will be omitted or simplified as appropriate. In the following embodiments, the word "unit" may be read as "circuit," "step," "procedure," "process," or "circuitry" as appropriate.

[0009] Embodiment 1 A multi-layer constellation 1 according to a first embodiment will be described with reference to FIGS.

[0010] (Information exchange between mission satellites and communication networks) A system for quickly exchanging information with Mission Satellite 30M, a low-orbit satellite equipped with various mission equipment, is highly anticipated. A mission equipment is a device that performs a specific mission. For example, a monitoring device that monitors a flying object as part of a mission is a mission equipment, and a monitoring satellite equipped with the monitoring device is Mission Satellite 30M. The exchange of information between the mission satellite and a communication network formed by multiple communication satellites has been an issue.

[0011] (Global Service) Furthermore, there is a strong demand for a satellite constellation that can provide global services in low latitudes, mid latitudes, and high latitudes including the poles. In the first embodiment, a mission satellite 30M forms a constellation (same orbital plane) that can communicate with satellites before and after it in the same orbital plane. Then, a multi-layer constellation 1 is formed by connecting multiple satellite constellations formed at different orbital altitudes via communication lines. The multi-layer constellation 1 of the first embodiment, which will be described later, realizes a satellite mission that can send and receive information globally and quickly.

[0012] Figure 1 shows polar orbits 81, inclined orbits 82, and equatorial orbits 83 above the Earth 600. In recent years, numerous mega-constellations using low-orbit satellites have been planned and construction has begun. The inclined orbits 82 and equatorial orbits 83 have the problem that they cannot provide service to high latitudes, including the polar regions. The polar orbit satellites 31 have the problem that a large number of satellites are required to provide comprehensive service to low latitudes near the equator. In addition, there is a problem that a huge number of satellites is generally required to provide comprehensive global service using low-orbit satellites.

[0013] (Polar orbit 81, inclined orbit 82, and equatorial orbit 83) On the other hand, by combining the advantages of polar orbits 81, inclined orbits 82, and equatorial orbits 83, it is expected that globally comprehensive services can be provided with fewer satellites. For example, if there is a satellite constellation of polar orbiting satellites 31 in one orbital plane, all satellites will pass through the polar regions once a week, so high latitudes including the polar regions can be covered. Also, if there is a satellite constellation of equatorial orbits 83 in one orbital plane, low latitudes can be covered.

[0014] (inclined orbit 82) In order for an inclined orbit satellite constellation to cover both high and low latitudes, a large number of satellites are required. However, if polar orbit satellites 31 and equatorial orbit satellites 33 are separately assigned to cover both high and low latitudes, it is possible to achieve global coverage even with a reduced number of inclined orbit satellites 32 in the inclined orbit satellite constellation. In the first embodiment, as described below, a multi-layer constellation 1 is configured with one polar orbit 81, six inclined orbits 82, and one equatorial orbit 83.

[0015] (collision risk avoidance) If the satellite constellations of polar orbit 81, inclined orbit 82, and equatorial orbit 83 fly at the same orbital altitude, there is a risk of collision at the orbital intersection. For this reason, the satellite constellation 11 of polar orbit 81, the satellite constellation 12 of inclined orbit 82, and the satellite constellation of equatorial orbit 83 are formed at different orbital altitudes. As shown in Figure 1, it is reasonable to form a multi-layer constellation 1 that connects satellite constellations 11 and 12, satellite constellations 12 and 13, and satellite constellations 13 and 11 via communication lines 15, 16, and 17, respectively.

[0016] (Ring Network 21) 2 shows a circular communication network 21. In a polar orbit 81 or an equatorial orbit 83, if the orbital altitude is about 600 km, eight or more communication satellites 30 can fly in a chain in the same orbit and communicate with the satellites before and after them to form the circular communication network 21. If the orbital altitude is higher, the circular communication network 21 can be formed with a smaller number of communication satellites 30. Also, as shown in FIG. 2, if one communication satellite 30-1 in the same orbit in the circular communication network 21 can communicate with the ground system 700, all communication satellites 30 in the circular communication network 21 can communicate with the ground system 700.

[0017] (Mesh communication network 22) In addition, in an inclined orbit 82, if a communication satellite 30 in the same orbital plane communicates with satellites in front and behind it to form a circular communication network 21, and then communicates with satellites in adjacent orbits, a mesh communication network 22 can be formed.

[0018] (Communications Satellite 30) FIG. 3 is a four-view diagram of the communication satellite 30. In the XYZ coordinate system shown in FIG. 3, the X axis indicates the direction of travel of the communication satellite 30, and the Z axis indicates the direction toward the Earth. Black circles indicate visible communication devices, and white circles indicate invisible communication devices for convenience. The communication satellite 30 is equipped with a first communication device 51C, a second communication device 52C, a third communication device 53C, a fourth communication device 54C, and a terrestrial communication device 55C. As shown in the XZ plane, the first communication device 51C, the second communication device 52C, and the terrestrial communication device 55C are arranged on the Earth-directed plane 18 facing the Earth 600. The first communication device 51C and the second communication device 52C realize the front-rear communication device 35. The first communication device 51C communicates with a second communication device 52C of a communication satellite 30 flying ahead of the communication satellite 30, and the second communication device 52C communicates with a first communication device 51C of a communication satellite 30 flying behind the communication satellite 30. A third communication device 53C and a fourth communication device 54C are arranged on an anti-earth-pointing surface 19 on the back side of the earth-pointing surface 18. The third communication device 53C and the fourth communication device 54C realize the left-right communication device 36. As described below, the third communication device 53C communicates with a fourth communication device 54C of a communication satellite 30 flying in an adjacent orbit on the right (east side), and the fourth communication device 54C communicates with a third communication device 53C of a communication satellite 30 flying in an adjacent orbit on the left (west side).

[0019] The first communication device 51C is arranged ahead of the direction of travel of the communication satellite 30. The first communication device 51C has a communication field of view 51 in the direction of travel of the communication satellite 30. The second communication device 52C is arranged behind the first communication device 51C in the direction of travel of the communication satellite 30. The second communication device 52C has a communication field of view 52 in the opposite direction to the direction of travel of the communication satellite 30.

[0020] The third communication device 53C and the fourth communication device 54C are arranged on the anti-earth-pointing plane 19, which is the back side of the earth-pointing plane 18 and faces in the opposite direction of the geocentric direction +Z. The third communication device 53C is arranged forward in the direction of flight. The third communication device 53C has a communication field of view 53 forward in the direction of flight. The third communication device 53C establishes crosslink communication in the northeasterly direction with the communication satellite 30 flying in an adjacent orbit on the east side, which is the right side. The fourth communication device 54C is arranged behind the third communication device 53C in the direction of flight. The fourth communication device 54C has a communication field of view 54 in the opposite direction to the direction of flight. The fourth communication device 54C establishes crosslink communication in the southwesterly direction with the communication satellite 30 flying in an adjacent orbit on the west side, which is the left side.

[0021] (Ground communication device 55C) As described for communication satellite 30-1 in Figure 2, communication satellite 30 in the orbital plane may be equipped with ground communication device 55C that communicates with ground system 700. In an inclined circular orbit with an orbital inclination angle of 40 degrees or more and 60 degrees or less, the north-south flight direction reverses at the north-south ends of the orbital plane, causing communication satellite 30 to temporarily fly from west to east. In this case, a satellite-dense zone where satellites fly from west to east is formed above an area on the Earth's surface between latitudes of 40 degrees or more and 60 degrees or less. Therefore, ground system 700 located between latitudes of 40 degrees or more and 60 degrees north or between latitudes of 40 degrees or more and 60 degrees south can frequently establish crosslink communications with the satellite constellation.

[0022] (Circular communication network 21 using inclined orbit 82) FIG. 4 is a diagram illustrating the circular communication network 21 on the inclined orbit 82. As shown in FIG.

[0023] (Ring Network 21) FIG. 4 shows an example in which a flying communication satellite 30 communicates with satellites flying before and after it in the same orbital plane in an inclined orbit 82. As shown in FIG. 4, the front-rear communication device 35 communicates with the communication satellites 30 flying before and after it in the same orbital plane. Specifically, the front-rear communication device 35 of the communication satellite 30 forms a bidirectional communication link 71 with the front-rear communication device 35 of the communication satellite 30 flying before and after it in the same orbital plane. By forming the communication link 71, the satellites flying before and after it in the same orbital plane can communicate bidirectionally. In FIG. 4, six or more communication satellites 30 flying in the same orbital plane form communication links 71 with the front-rear communication satellites 30, thereby forming a circular communication network 21 that circles the Earth 600. The above description also applies to the circular communication network 21 in a polar orbit 81 and an equatorial orbit 83.

[0024] FIG. 5 is a diagram showing an example in which a communication satellite 30 communicates with satellites flying in adjacent inclined orbits 82 on the left and right (east and west). As shown in FIG. 5, the left and right communication devices 36 communicate with the communication satellite 30 flying in the adjacent orbit. Specifically, the left and right communication devices 36 of the communication satellite 30 form bidirectional communication links 72 with the left and right communication devices 36 included in the communication satellites 30 flying in the adjacent orbits. In FIG. 5, the left and right communication devices 36 of the communication satellite 30 form bidirectional communication links 72 with the left and right communication devices 36 included in the communication satellites 30 flying in adjacent orbits on the east and west sides. By forming the communication links 72, bidirectional communication with the satellites flying in the adjacent orbits becomes possible.

[0025] (Mesh communication network 22) Figure 6 shows a mesh communication network 22. In the satellite constellation 12 in an inclined orbit 82, the circular communication networks 21 in the same orbital plane described in Figure 5 are connected by the communication links 72 described in Figure 5, thereby forming the mesh communication network 22 shown in Figure 6.

[0026] (Flying Object System) infra-red lineIn a missile tracking system that tracks a missile using a monitoring satellite 30S equipped with a monitoring device, after detecting the launch of a missile, the direction of flight and the impact point of the missile are unknown. Therefore, the missile information acquired by the monitoring satellite must be transmitted to other monitoring satellites. This poses a problem in that the exchange of information with communication satellites to transmit the missile information becomes complicated.

[0027] (equatorial orbit 83) To address this issue, a hybrid constellation is constructed that includes a monitoring satellite 40 that communicates with the communication satellites 30 before and after it, between the communication satellites 30 of the multiple communication satellites 30 that form the circular communication network 21 in the same orbital plane. This has the effect of allowing the flying object information acquired by the monitoring satellite 40 to be immediately transmitted over the communication network. A "hybrid constellation" is a constellation that reconstructs the circular communication network 21 by incorporating a mission satellite 30M that performs a specific mission between the communication satellites 30 that fly before and after the communication satellites 30 in the circular communication network 21. The mission satellite 30M is configured as the communication satellite 30 in Figure 3 equipped with a mission device 31M. FIG. 7 shows a hybrid constellation in which a mission satellite 30M is added to the circular communications network 21 of the satellite constellation 11 in a polar orbit 81. The mission satellite 30M, which is a communications satellite 30-2, is equipped with a mission equipment 31M. The satellite constellation 12 in an inclined orbit 82 and the satellite constellation 12 in an equatorial orbit 83 are similar to the satellite constellation 11 in a polar orbit 81. Note that while FIG. 2 shows eight satellites, if six or more communications satellites 30 fly evenly in the longitude direction in the equatorial orbit 83, a circular communications network 21 can be constructed, which has the effect of enabling comprehensive monitoring of low latitudes.

[0028] (polar orbit 81) 7 shows eight satellites, but if six or more satellites fly evenly in the longitude direction in polar orbit 81, it is possible to construct a circular communication network 21. Since communication satellite 30 passes through the polar regions on every revolution in polar orbit 81, it has the effect of being able to comprehensively monitor the polar regions and high latitudes even in a single orbital plane.

[0029] (Mesh communication network 22 on inclined orbit 82) In the inclined orbit 82, 36 or more communication satellites 30 are distributed in the orbital plane in the longitude direction. A circular communication network is constructed by communication with the satellites before and after each orbital plane. The circular communication networks 21 in adjacent orbits are connected by the communication link 72 described in Figure 5 to construct a mesh communication network 22. The mesh communication network 22 has the advantage of enabling comprehensive monitoring of the mid-latitudes.

[0030] If communication satellites 30 in polar orbit 81, inclined orbit 82, and equatorial orbit 83 fly at the same orbital altitude, there is a risk of collision at the orbital intersection (Figure 1). Therefore, in multi-layer constellation 1, satellite constellation 11 in polar orbit 81, satellite constellation 12 in inclined orbit 82, and satellite constellation 13 in equatorial orbit 83 each have different orbital altitudes, and each communicates with each other as shown in Figure 1. This has the effect of enabling global monitoring of the Earth and enabling monitoring information to be shared instantly via a communication network.

[0031] A hybrid constellation including a monitoring satellite 30S equipped with an equatorial monitoring device is formed as a multi-layer constellation 1, which is capable of communicating with each other, consisting of a satellite constellation 11 in a polar orbit 81, a satellite constellation 12 in an inclined orbit 82, and a satellite constellation 13 in an equatorial orbit 83. This has the effect of enabling detection and tracking of the launch of a flying object, and enabling rapid preparations to deal with the flying object.

[0032] Multi-layer constellation 1 will be explained below.

[0033] <Multi-layer constellation: Type 1> In the multi-layer constellation 1, a plurality of satellite constellations formed at different orbital altitudes form a communication network spanning multiple orbital altitudes. FIG. 8 is a conceptual diagram of a multi-layer constellation 1. In the multi-layer constellation 1, three satellite constellations 10-1, 10-2, and 10-3 formed at different orbital altitudes form a communications network spanning the three orbital altitudes. Satellite constellation 10-1 and satellite constellation 10-2 are connected by a communications line 5. Satellite constellation 10-2 and satellite constellation 10-3 are connected by a communications line 6. Satellite constellation 10-3 and satellite constellation 10-1 are connected by a communications line 7. As described in FIG. 2, each of the multiple satellite constellations forms a circular communications network 21 that extends all the way around the Earth 600, with a satellite sandwiched between two satellites in the same orbital plane in the direction of travel communicating with both the satellites in front and behind it in the direction of travel. At least one of the multiple satellite constellations is a hybrid constellation 2 that includes a mission satellite 30M that carries a mission equipment 31M that performs a specific mission and that communicates with satellites both in front of and behind it in the direction of travel. For example, the communication satellite 30-1 of the satellite constellation 10-1 is a mission satellite 30M that carries a mission equipment 31M.

[0034] The communication satellite 30 belonging to the multi-layer constellation 1 is a communication device equipped with a first communication device 51C and a second communication device 52C shown in FIG. 2. A plurality of satellite constellations 10-1, 10-2, and 10-3 formed at different orbital altitudes form a communication network spanning multiple orbital altitudes. As described above, the satellite constellation 10-1 is made up of a plurality of satellites equipped with front and rear communication devices that communicate with satellites in front and behind it in the direction of travel in the same orbital plane, forming a circular communication network 21. The satellite constellations 10-1, 10-2, and 10-3 are a hybrid constellation 2 in which a mission satellite 30M forms the circular communication network 21. The mission satellite 30M is equipped with a first communication device 51C and a second communication device 52C that communicate with the front and rear satellites, and further equipped with a mission device 31M. The satellite constellation 10-1 is a hybrid constellation in which a mission satellite 30M flies between satellites that form the satellite constellation and reconstructs a circular communication network 21.

[0035] As shown in Figure 8, a constellation of multiple satellites 10-1, 10-2, and 10-3 formed at different orbital altitudes and connected by communication lines 5, 6, and 7 is called a multi-layer constellation. A multi-layer constellation enables global services, including those in the polar regions and near the equator. Furthermore, while there is a risk of collision at orbital intersections when satellites fly at the same orbital altitude, the multi-layer constellation 1 in Figure 8 has different orbital altitudes, which has the advantage of ensuring the flight safety of the communication satellites 30. In a satellite constellation flying in formation at the same altitude in the same orbital plane, if communication crosslinks are established between the preceding and succeeding satellites via communication devices to form a circular communication network 21, it is possible to communicate information from all communication satellites in orbit. While Figure 8 shows eight satellites, the circular communication network 21 can be formed if six or more satellites in the same orbital plane communicate with each other via crosslinks. If one or more mission satellites 30M equipped with various mission devices such as surveillance, positioning, and information gathering fly in the same orbital plane and the circular communication network 21 is reconstructed, each mission satellite 30M can quickly transmit information via the circular communication network 21.

[0036] (Hybrid Constellation) In FIG. 8, if the satellites forming the circular communication network 21 include one or more communication satellites 30-1 (FIG. 2) that communicate with the ground system 700, the communication satellite 30-1 represents all communication satellites 30 on the same orbital plane, and each communication satellite 30 can exchange satellite information with the ground. Various mission satellites 30M equipped with various missions vary in function and cost. The hybrid constellation 2 has the advantage of allowing the configuration and combination of mission satellites 30M to be selected according to the configuration purpose and budget of the satellite constellation. This has the advantage of allowing the desired purpose to be achieved at low cost. The various mission devices may be mission devices other than communication devices, such as observation devices, positioning devices, and information collection devices, or may be communication devices such as data relay devices and devices for communicating with various ground assets including mobile objects.

[0037] <Multi-layer constellation: Type 2> The multi-layer constellation 1 may be configured as follows. At least one of the multiple satellite constellations has multiple orbital planes in which a circular communication network is formed. In this satellite constellation, each satellite flying in each of the multiple orbital planes communicates with both a left-side satellite flying in an adjacent orbit on the left side and a right-side satellite flying in an adjacent orbit on the right side, thereby forming a mesh communication network 22 in which adjacent circular communication networks 21 are communicatively connected to each other. Specifically, the multi-layer constellation 1 includes a satellite constellation 11 (FIG. 1) in one polar orbit 81, a satellite constellation 13 (FIG. 1) in one equatorial orbit 83, and a satellite constellation 12 (FIG. 6) in an inclined orbit 82 consisting of multiple orbital planes. A circular communication network 21 is formed in each orbital plane of the inclined orbit 82, and the circular communication networks 21 are connected as the mesh communication network 22 by communication links 72, as shown in FIGS. 5 and 6. 8, at least one of the satellite constellations includes a mission satellite 30M. Also, at least one of the satellite constellations may include a communication satellite 30 having a ground communication device 55C.

[0038] Multi-layer constellation 1 with the above configuration enables comprehensive global service, including the polar regions and near the equator. Furthermore, depending on the orbital altitude, global service can be achieved with a minimum number of satellites: six or more in polar regions, six or more above the equator, and 36 or more in inclined orbits (six orbital planes x six satellites per orbital plane), for a total of 48 or more. Multi-layer constellation 1 with the above configuration has the effect of enabling comprehensive global information transmission for various missions. One advantage of using a hybrid constellation is that when information detected by a monitoring satellite needs to be quickly transmitted to a response asset, such as in a missile response system, there is no need to interface the monitoring satellite with a communications satellite. Therefore, information from the monitoring satellite can be instantly transmitted to the response asset via the communications network, allowing the response asset time to prepare.

[0039] <Multi-layer constellation: Type 3> The multiple satellite constellations that make up the multi-layer constellation 1 in the above-mentioned <Multi-layer Constellation: Type 1> or <Multi-layer Constellation: Type 2> are as follows: The multiple satellite constellations that make up the multi-layer constellation 1 are composed of a satellite constellation 11 in a polar orbit 81, a satellite constellation 12 in an inclined orbit 82, and a satellite constellation 13 in an equatorial orbit 83. Alternatively, the multiple satellite constellations that make up the multi-layer constellation 1 are composed of any two of the satellite constellation 11 in a polar orbit 81, the satellite constellation 12 in an inclined orbit 82, and the satellite constellation 13 in an equatorial orbit 83.

[0040] Combining polar orbits 81, inclined orbits 82, and equatorial orbits 83 allows each orbit to complement each other, enabling global services. Combining satellite constellations with inclined orbits 82 at different orbital altitudes allows for synchronized operation by matching the orbital periods of satellites with different orbital inclination angles. Even when the orbital altitudes required for operation vary depending on the mission objective, the mesh communication network 22 can be utilized as a common communications infrastructure. Therefore, a multi-layer constellation 1 combining inclined satellites with different orbital altitudes is also acceptable. In a missile response system, a constellation of surveillance satellites detects and tracks missiles and quickly transmits them to response assets deployed in the ground area where the missile is expected to land. For this reason, data relay satellites deployed at high altitudes are effective. High-altitude polar orbit satellites or high-altitude equatorial satellites enable continuous data relay to response assets with a small number of satellites. The <Multi-layer Constellation: Type 3> configuration eliminates orbital intersections between satellite constellations, thereby eliminating the risk of collision.

[0041] <Projectile Tracking System: Type 1> The multi-layer constellation 1 may have the following configuration: A hybrid constellation 2 as shown in Figs. 7 and 8 includes a mission satellite 30M and an infrared satellite 31M as a mission device. line The system includes a plurality of monitoring satellites 30S each carrying a monitoring device 32S.

[0042] If the multi-layer constellation 1 has the above configuration, the launch of a flying object whose flight direction and impact point are unknown at the time of launch can be detected by the infrared light of the monitoring satellite 30S. line When a flying object is detected by the monitoring device 32S, information about the detected flying object can be transmitted to anywhere in the world via a communication network. This has the effect of enabling a rapid response in emergencies. Furthermore, to track a flying object, it is necessary to detect the flying object using a subsequent monitoring satellite. However, the multi-layer constellation 1 configured as described above has the effect of being able to issue commands to any monitoring satellite. To detect the flying object itself during flight, where temperature rise is not significant, limb observation, which monitors the Earth's periphery against a cosmic background, is suitable. If the multi-layer constellation 1 shown in Figure 8 is equipped with a monitoring satellite as the mission satellite 30M, it can monitor flying objects flying in the mid-latitude direction in the longitude direction from an equatorial orbit 83, monitor high and low latitudes from an inclined orbit 82, and monitor the polar regions from a polar orbit 81. This has the effect of enabling limb observation in the skies above the globe.

[0043] <Projectile Tracking System: Type 2> The multi-layer constellation 1 may have the following configuration: One or more of the multiple monitoring satellites 30S (FIG. 8) may be infrared line The monitoring device 32S is used to perform limb observations directed toward the edge of the Earth to detect flying objects. The flight position of the detected flying object is measured by aerial triangulation based on the positions of multiple communication satellites 30 flying in the multi-layer constellation 1.

[0044] (1) When a projectile is launched, a spray called a plume spreads into the heated atmosphere. This allows monitoring from a distance, such as from a geostationary orbit. However, tracking and monitoring a projectile that stops firing, such as one that repeats intermittent firing, requires that the temperature rise is not as high as that of the plume and that the temperature of the projectile itself be detected. Therefore, a much higher spatial resolution is required than for plume monitoring, which monitors the diffuse atmosphere, and a low-Earth orbit monitoring satellite is required. To track and monitor a projectile that has stopped firing, it is reasonable to use deep space, where the background temperature is low and stable, as a background. Rim observations aimed at the Earth's periphery are effective. Rim observations are suitable for monitoring projectiles flying longitudinally through mid-latitudes from equatorial orbits, while projectiles passing through the polar regions can be monitored by polar-orbiting satellites. When monitoring and communications satellites form separate constellations, the monitoring satellite must transmit the projectile tracking information it has acquired to the communications satellite, using commands that specify the satellite ID and the time of transmission. This makes operations extremely complicated and results in lost waiting time for information exchange.In contrast, with Hybrid Constellation 2 (Figure 8), the monitoring satellite can instantly transmit the information on the flying object observed by the limb to the communication network, allowing the subsequent monitoring satellite to track and monitor the flying object. (2) Figure 9 shows limb observations of a polar orbit 81, an inclined orbit 82, and an equatorial orbit 83. In order to measure the flight position of a flying object, aerial triangulation from three directions with known position coordinates and different line-of-sight vectors is effective. Combining limb observation information from the polar orbit 81, the inclined orbit 82, and the equatorial orbit 83 has the effect of making it possible to measure the position of the flying object.

[0045] <Sharing of information about flying objects> The multi-layer constellation 1 may have the following configuration. See Fig. 1, Fig. 6, Fig. 8, etc. line The flying object information acquired by the monitoring device 32S is transmitted and received by a plurality of communication satellites 30 belonging to the multi-layer constellation 1.

[0046] In this <sharing of missile information>, the missile information consisting of the missile launch time and launch position information transmitted by a monitoring satellite that has detected or tracked and monitored the missile launch is transmitted to all satellites that make up the multi-layer constellation 1 via the mesh communication network 22. This has the effect of enabling the monitoring satellites flying in the polar orbit 81, inclined orbit 82, and equatorial orbit 83 to prepare for tracking and monitoring based on fast and accurate flight position information.

[0047] <Synchronization control signal> The multi-layer constellation 1 may have the following configuration. See Figures 1, 6, 8, etc. The hybrid constellation 2 includes a clock satellite as a plurality of mission satellites 30M, which is a mission device 31M equipped with a high-precision master clock and transmits a synchronization control signal based on the high-precision master clock. In the multi-layer constellation 1, the other plurality of satellites belonging to the multi-layer constellation 1 exchange synchronization control signals.

[0048] Even if each satellite in the constellation does not have a high-precision clock, the synchronization control signal transmitted by the master clock satellite enables highly accurate time management. For example, if the mission equipment is a positioning device, the synchronization control signal transmitted by the master clock satellite can be used to transmit highly accurate positioning signals from positioning satellites that do not have atomic clocks. By equipping geostationary satellites and quasi-zenith satellites with master clocks and controlling them in synchronization with low-orbit positioning satellites, low-orbit satellites can perform positioning without having to use expensive equipment such as atomic clocks, which reduces costs.

[0049] <In-orbit generation command information> The multi-layer constellation 1 may have the following configuration. See Figures 1, 6, 8, etc. A satellite in orbit belonging to the multi-layer constellation 1 generates command information for the mission device 31M. The multiple satellites belonging to the multi-layer constellation 1 exchange command information with each other.

[0050] By automatically generating command information for mission equipment in orbit and transmitting it between satellites, rapid coordinated operation of multiple satellites is possible without the time delay of traveling via the ground.For example, in a flying object tracking system, a satellite that detects a launch automatically generates the position coordinates of the launch point in orbit and transmits monitoring instruction command information to another monitoring satellite as the monitoring target position coordinates, enabling rapid tracking of the flying object.In addition, if the number of satellites becomes enormous and a collision risk occurs, there is a concern that evasive action will not be able to be taken in time via the ground system, so by using artificial intelligence (AI) to perform collision analysis in orbit and autonomously generating commands in orbit to perform evasive action for satellites at risk of approaching and colliding, and transmitting command information, it is possible to quickly take evasive action.

[0051] The mission satellite 30M is equipped with a mission device 31M, which may be an optical information gathering device, a radio wave information gathering device, a laser generator, a radio wave generator, an infrared monitoring device 32S, a positioning signal generator, a radio wave data relay device, or an optical data relay device.

[0052] <Supplementary information on the satellite hardware configuration> 10 shows a hardware configuration in the case where the satellite 60 is a communication satellite 30 that forms a multi-layer constellation 1. The hardware configuration of the communication satellite 30 will be described with reference to FIG.

[0053] The satellite 60 comprises a satellite control device 61, a communication device 62, a propulsion device 63, an attitude control device 64, and a power supply device 65. Although the satellite 60 may also comprise other components that realize various other functions, only the satellite control device 61, the communication device 62, the propulsion device 63, the attitude control device 64, and the power supply device 65 will be described in Fig. 10.

[0054] (1) The satellite control device 61 is a computer that controls the propulsion device 63 and the attitude control device 64, and includes a processing circuit. Specifically, the satellite control device 61 controls the propulsion device 63 and the attitude control device 64 in accordance with various commands transmitted from the ground system 700. (2) The communication device 62 corresponds to the first communication device 51C, the second communication device 52C, the third communication device 53C, the fourth communication device 54C, and the ground communication device 55C. (3) The propulsion device 63 is a device that provides thrust to the satellite 60 and changes the speed of the satellite 60. (4) The attitude control device 64 is a device for controlling attitude elements such as the attitude of the satellite 60, the angular velocity of the satellite 60, and the line of sight (LOS). The attitude control device 64 changes each attitude element to a desired direction. Alternatively, the attitude control device 64 maintains each attitude element in a desired direction. The attitude control device 64 includes an attitude sensor, an actuator, and a controller. The attitude sensor is a device such as a gyroscope, an earth sensor, a sun sensor, a star tracker, a thruster, and a magnetic sensor. The actuator is a device such as an attitude control thruster, a momentum wheel, a reaction wheel, and a control moment gyro. The controller controls the actuator according to the measurement data of the attitude sensor or various commands from the ground system 700. (5) The power supply unit 65 includes devices such as a solar cell, a battery, and a power control device, and supplies power to each device mounted on the satellite 60.

[0055] The processing circuit provided in the satellite control device 61 will now be described. The processing circuit may be dedicated hardware or a processor that executes a program stored in memory. In the processing circuit, some functions may be realized by dedicated hardware and the remaining functions may be realized by software or firmware. In other words, the processing circuit can be realized by hardware, software, firmware, or a combination of these. Specifically, the dedicated hardware may be a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC, an FPGA, or a combination of these. ASIC is an abbreviation for Application Specific Integrated Circuit. FPGA is an abbreviation for Field Programmable Gate Array.

[0056] FIG. 11 shows the hardware configuration when the satellite 60 is a monitoring satellite. In the following, the satellite 60 is assumed to be a monitoring satellite. In the case of an observation satellite, the satellite 60 is equipped with an observation device. The satellite 60 in FIG. 11 includes a monitoring device 66 in addition to the configuration shown in FIG. 10. The monitoring device 66 is a device for monitoring objects. Specifically, the monitoring device 66 is a device for monitoring or observing objects such as space objects, flying objects, or land, sea, and air vehicles. The monitoring device 66 is also referred to as an observation device. For example, the monitoring device 66 is an infrared monitoring device that uses infrared light to detect the temperature rise caused by atmospheric friction when a flying object enters the atmosphere. The monitoring device 66 detects the temperature of the plume or the flying object itself at the time of launch. Alternatively, the monitoring device 66 may be an optical or radio wave information gathering device. The monitoring device 66 may also be a device that detects objects using an optical system. The monitoring device 66 uses an optical system to photograph objects flying at an altitude different from the orbital altitude of the observation satellite. In particular, the monitoring device 66 may be a visible optical sensor.

[0057] <Hardware configuration of ground system 700>

[0058] 12 shows the hardware configuration of the ground system 700. The ground system 700 communicates with the monitoring satellite and the communication satellite 30 that constitutes the multi-layer constellation 1, and controls the operations of the communication satellite 30 and the monitoring satellite. The ground system 700 is connected to a ground-side communication device 810, and communicates with the satellite via the ground-side communication device 810. The ground system 700 may also include a mobile terminal.

[0059] The ground system 700 forms the multi-layer constellation 1 and the hybrid constellation 2 by communicating with each satellite 60. The ground system 700 includes a processor 710 as well as other hardware such as a main memory device 720, an auxiliary memory device 730, an input interface 740, an output interface 750, and a communication interface 760. In Fig. 12, the interfaces are denoted as IF. The processor 710 is connected to other hardware via a signal line 770 and controls this other hardware.

[0060] The ground system 700 includes, as a functional element, a control unit 711. The functions of the control unit 711 are realized by hardware or software.

[0061] The above describes embodiment 1. Of the multiple technical features of embodiment 1, one may be partially implemented, or two or more of the multiple technical features of embodiment 1 may be combined and implemented. [Explanation of symbols]

[0062] 1 Multi-layer constellation, 2 Hybrid constellation, 5, 6, 7 Communication link, 10, 10-1, 10-2, 10-3, 11, 12, 13 Satellite constellation, 15, 16, 17 Communication link, 18 Earth pointing plane, 19 Anti-Earth pointing plane, 21 Circular communication network, 22 Mesh communication network, 30 Communication satellite, 30A Ground communication satellite, 30M Mission satellite, 31M Mission equipment, 31 Polar orbit satellite, 32 Inclined orbit satellite, 33 Equatorial orbit satellite, 35 Forward and backward communication device, 36 Left and right communication device, 30S Surveillance satellite, 31S Surveillance equipment, 51 Communication field of view, 51C First communication device, 52 Communication field of view, 52C Second communication device, 53 Communication field of view, 53A Right communication direction, 53C Third communication device, 54 Communication field of view, 54A Left communication direction, 54C fourth communication device, 55C ground communication device, 60 satellite, 61 satellite control device, 62 communication device, 63 propulsion device, 64 attitude control device, 65 power supply device, 66 monitoring device, 71 communication link, 72 communication link, 81 polar orbit, 82 inclined orbit, 83 equatorial orbit, 90 ground data center, 600 Earth, 700 ground system, 710 processor, 720 main memory device, 730 auxiliary memory device, 740 input interface, 750 output interface, 760 communication interface, 770 signal line, 810 ground communication device.

Claims

1. A multi-layer constellation in which a plurality of satellite constellations formed at different orbital altitudes form a communication network spanning a plurality of orbital altitudes, Each satellite constellation of the plurality of satellite constellations comprises: A satellite sandwiched between two satellites in the same orbital plane communicates with both satellites in the front and rear of the satellite in the direction of travel, forming a circular communication network that covers the entire circumference of the Earth. At least one of the plurality of satellite constellations comprises: In a multi-layer constellation that is a hybrid constellation that includes two or more types of mission satellites, the satellites that communicate with both satellites in front and behind the direction of travel are observation satellites equipped with observation equipment, positioning satellites equipped with positioning equipment, information gathering satellites equipped with information gathering equipment, data relay satellites equipped with data relay equipment, and communication satellites equipped with communication equipment that communicates with various ground assets including mobile objects, The plurality of satellite constellations includes: It consists of a polar orbital constellation, an inclined orbital constellation, and an equatorial orbital constellation, The circular communication network of the polar orbit constellation, the circular communication network of the inclined orbit constellation, and the circular communication network of the equatorial orbit constellation are They are connected to each other by communication lines, The mission satellite transmitting and receiving information to and from the circular communication networks of the polar orbital constellation, the inclined orbital constellation, and the equatorial orbital constellation; At least one of the plurality of satellite constellations comprises: A multi-layer constellation is a hybrid constellation that incorporates the mission satellite as the satellite that communicates with both satellites in front and behind the direction of travel, thereby reconstructing a circular communication network.

2. The inclined orbit constellation comprises:

2. The multi-layer constellation of claim 1, comprising a plurality of orbital planes on which the annular communication network is formed, and each satellite flying in each of the plurality of orbital planes is provided with a front-rear communication device for communicating with communication satellites flying in front and behind the same orbital plane, and a left-right communication device for communicating with communication satellites flying in adjacent orbits, wherein each satellite flying in each of the plurality of orbital planes communicates with both a left-side satellite flying in an adjacent orbit on the left side and a right-side satellite flying in an adjacent orbit on the right side, thereby forming a mesh communication network in which adjacent annular communication networks are connected to each other so that they can communicate with each other.

3. The hybrid constellation 3. The multi-layer constellation according to claim 1, wherein the mission satellites are a plurality of monitoring satellites each equipped with an infrared monitoring device that is a mission device for performing a specific mission.

4. One or more monitoring satellites among the plurality of monitoring satellites conducting limb observations directed toward the Earth's periphery using the infrared monitoring device to detect flying objects; The detected flight position of the flying object is The multi-layer constellation according to claim 3 , wherein the multi-layer constellation is measured by aerial triangulation based on the positions of a plurality of satellites flying over the multi-layer constellation.

5. The flying object information acquired by the infrared monitoring device mounted on the monitoring satellite, The multi-layer constellation according to claim 3 or 4, wherein the signal is transmitted and received by a plurality of satellites belonging to the multi-layer constellation.

6. The hybrid constellation The plurality of mission satellites include a clock satellite that is a mission device that performs a specific mission and includes a high-precision master clock and transmits a synchronization control signal based on the high-precision master clock; In the multi-layer constellation, The other plurality of satellites belonging to the multi-layer constellation include:

6. A multi-layer constellation according to claim 1, which transmits and receives the synchronization control signal.

7. The satellites in orbit belonging to the multi-layer constellation include: Automatically generate command information for the mission equipment to carry out a specific mission in orbit, The plurality of satellites belonging to the multi-layer constellation are Sending and receiving the command information, A multi-layer constellation as described in any one of claims 1 to 6, wherein a monitoring satellite among a plurality of satellites belonging to the multi-layer constellation that detects a projectile launch automatically generates position coordinates of the launch point that detected the projectile launch on orbit, and transmits monitoring instruction command information indicating the position coordinates as monitoring target position coordinates to another monitoring satellite belonging to the multi-layer constellation.

8. The mission satellite is a mission device that performs a specific mission, 8. A multi-layer constellation according to any one of claims 1 to 7, which is equipped with an optical information gathering device, a radio wave information gathering device, a laser generator, a radio wave generator, an infrared monitoring device, a positioning signal generator, a radio wave data relay device, or an optical data relay device.

9. A multi-layer constellation in which a plurality of satellite constellations formed at different orbital altitudes form a communication network spanning a plurality of orbital altitudes, Each satellite constellation of the plurality of satellite constellations comprises: A satellite sandwiched between two satellites in the same orbital plane communicates with both satellites in the front and rear of the satellite in the direction of travel, forming a circular communication network that covers the entire circumference of the Earth. At least one of the plurality of satellite constellations comprises: A multi-layer constellation is a hybrid constellation that reconstructs a circular communication network by incorporating two or more types of mission satellites from among the following satellites that communicate with both satellites in front and behind the direction of travel: observation satellites equipped with observation equipment, positioning satellites equipped with positioning equipment, information gathering satellites equipped with information gathering equipment, data relay satellites equipped with data relay equipment, and communication satellites equipped with communication equipment that communicates with various ground assets including mobile objects.

10. A multi-layer constellation in which a plurality of satellite constellations formed at different orbital altitudes form a communication network spanning a plurality of orbital altitudes, Each satellite constellation of the plurality of satellite constellations comprises: A satellite sandwiched between two satellites in the same orbital plane communicates with both satellites in the front and rear of the satellite in the direction of travel, forming a circular communication network that covers the entire circumference of the Earth. At least one of the plurality of satellite constellations comprises: a plurality of orbital planes on which the annular communication network is formed, and each satellite flying on each of the plurality of orbital planes communicates with both a left satellite flying on an adjacent orbit on the left side and a right satellite flying on an adjacent orbit on the right side, thereby forming a mesh communication network in which adjacent annular communication networks are connected to each other so that they can communicate with each other; At least one of the plurality of satellite constellations comprises: The satellites that communicate with both the forward and backward satellites in the direction of travel include two or more types of mission satellites selected from observation satellites equipped with observation equipment, positioning satellites equipped with positioning equipment, information gathering satellites equipped with information gathering equipment, data relay satellites equipped with data relay equipment, and communication satellites equipped with communication equipment for communicating with various ground assets including mobile objects; A multi-layer constellation is a hybrid constellation that incorporates the mission satellite as the satellite that communicates with both satellites in front and behind the direction of travel, thereby reconstructing a circular communication network.

Images