JP3613188B2 - High altitude inclined orbit satellite communication positioning system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a high altitude orbit satellite communication positioning system that combines a tilted elliptical orbit and a satellite on an inclined circular orbit.
[0002]
[Prior art]
FIG. 7 shows, for example, the locus of the satellite in the conventional tilted orbit satellite communication positioning system shown in “Examination of satellite positioning error using quasi-zenith satellite system” (Science Technical Report SAT2000-55, pp. 1-5). FIG. 5 is a ground locus of the inclined circular orbit satellite.
[0003]
Next, the operation will be described using an example in which the vicinity of Japan is serviced.
First, the arrangement of the satellites is adjusted so that the three satellites 5a, 5b, and 5c move on the ground trajectory 5 of FIG. At least one of the three satellites always appears at a viewing angle above a certain elevation angle in the communication area centering on the northernmost end near Japan. Since the earth's rotation period is about 24 hours, the time interval of the three satellites is about 8 hours, and the satellites entering the viewing angle change every about 8 hours. Communication with the satellite is always performed by activating the satellite that is always within the viewing angle and putting the remaining two satellites that are outside the viewing angle into a non-active waiting state.
[0004]
FIG. 8 is a diagram showing a positional relationship between a satellite and a ground point used when positioning an arbitrary ground point using a satellite. In a satellite positioning system typified by GPS (Global Positioning System), usually, at least four satellites are used to calculate the three-dimensional position of the ground point and the time related to positioning. Of the various error factors that occur when performing this satellite positioning, the geometric error factor is determined by the positional relationship between the four satellites (71 to 74) and the ground point (user position) of the earth 6. FIG. 9 is an explanatory diagram showing a configuration of a tetrahedron for determining a geometric error amount. Connecting the end points of the unit vectors (91 to 94) from the user position 8 to the direction of each satellite results in a tetrahedron 10, and the inverse of the volume of the tetrahedron 10 is a value proportional to the error coefficient. Therefore, the larger the volume of the tetrahedron 10, the smaller the error. When the volume is the largest, the tetrahedron 10 is a regular tetrahedron. The optimal configuration is that the end point forms a regular tetrahedron.
[0005]
In the first example shown in the conventional example, GPS satellites are adopted as three satellites corresponding to the unit vectors constituting the three vertices of the bottom face of the tetrahedron, and the units constituting the vertices not included in the bottom face of the tetrahedron A tilted circular orbit satellite is adopted as the satellite corresponding to the vector. By combining tilted circular orbit satellites having high elevation angle characteristics with GPS satellites, the positioning inability due to the blocking effect in urban areas caused by the low elevation angle characteristics of GPS is improved.
Furthermore, in the second example shown in the conventional example, satellite positioning is performed by combining a tilted circular orbit satellite and a geostationary satellite. In other words, the positioning system is configured by combining with existing domestic systems.
[0006]
[Problems to be solved by the invention]
For example, when a conventional satellite communication positioning system is combined with an existing positioning system such as GPS, it is necessary to use another system, and there is a problem that positioning unique to the system cannot be performed.
[0007]
In addition, when combined with existing geostationary satellites, for example, the elevation angle of geostationary satellites seen from a high latitude region is low, so there is a problem that the high elevation angle characteristics in the high latitude region, which is a feature of inclined orbit satellites, cannot be utilized. .
[0008]
The present invention has been made to solve the above problems, and an object of the present invention is to provide a satellite communication positioning system capable of performing both highly reliable communication and positioning uniquely.
[0009]
[Means for Solving the Problems]
The high altitude orbit satellite communication positioning system of the invention according to claim 1 is a period in which each satellite period in orbit is synchronized with the rotation of the earth, and an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising a total of three satellites, each having a phase difference of 120 degrees on three inclined elliptical orbits, and a period in which each satellite period on the orbit is synchronized with the rotation of the earth, Inclined circular orbit satellite comprising six satellites each having a phase difference of 60 degrees on six inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal. The system is used so that the center longitude of the ground trajectory of the tilted elliptical orbit and the tilted circular orbit is the same, and the satellite altitude of either the southernmost or the northernmost end of the tilted elliptical orbit satellite is high. A total of 8 hours, 4 hours before and after the time passing through the direction, is used as the operating time, and at least one of the satellites is always in operation by using the three satellites in sequence. When the orbit satellite trajectory is in the northern hemisphere or the southern hemisphere and the center of the operation time of the inclined elliptical orbit satellite is the operation time of the inclined circular orbit satellite, at least three of the six satellites are always In operation, perform ground positioning using a total of four satellites on the tilted elliptical orbit and the tilted circular orbit, and communicate using the satellite on the tilted elliptical orbit. Is to do.
[0010]
The high altitude orbit satellite communication positioning system of the invention according to claim 2 is a period in which each satellite period in the orbit is synchronized with the rotation of the earth, and the eccentricity and inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising at least three or more inclined elliptical orbits, each of which is arranged with an equal phase difference, a total of three or more satellites, and each satellite period in orbit is On an inclined circular orbit of at least 2N (N ≧ 4 natural number) having an inclination angle larger than that of the inclined elliptical orbit in which the ground trajectories of the respective satellites are equal in a period synchronized with the rotation of each of the satellites. A tilted circular orbit satellite system with a total of 2N (N ≧ 4 natural number) satellites arranged in phase difference, and the center longitude of the above-mentioned inclined elliptical orbit and the ground trajectory of the inclined circular orbit. The three or more satellites are used in sequence, with the predetermined time before and after centering on the time of passing the higher altitude of the satellite at the southernmost or northernmost end of the inclined elliptical orbit satellite. When it is used, at least one satellite is always operating, and the trajectory of the inclined circular orbit satellite is in the northern hemisphere or the southern hemisphere where the center of the operating time of the inclined elliptical orbit satellite is located. Is the operating time of the inclined circular orbit satellite, and at least N of the 2N (N ≧ 4 natural number) satellites are always in operation, and on the inclined elliptical orbit and the inclined circular orbit that are operating. Terrestrial positioning is performed using four satellites selected from (N + 1) or more satellites, and communication is performed using the satellites in the above-described inclined elliptical orbit.
[0011]
The high altitude orbit satellite communication positioning system of the invention according to claim 3 has an eccentricity and an inclination angle at which each satellite period in the orbit is half the rotation period of the earth and the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising at least three inclined elliptical orbits, each of which is arranged at an equal phase difference, with a total of three or more satellites, and each satellite period in orbit is An equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal in a period synchronized with the rotation. A tilted circular orbit satellite system with a total of 2N (N ≧ 3 natural number) satellites arranged at the position of the southernmost or northernmost position of the ground trajectory of the tilted elliptical orbit One of the ground trajectory points with the higher satellite altitude and the center longitude of the ground trajectory of the tilted circular orbit are used in the same way, passing through the one with the higher satellite altitude, either the southernmost or the northernmost end of the tilted elliptical orbit satellite. The operation time is a predetermined time before and after the operation time, and at least one satellite corresponding to one of the ground locus points matching the central longitude is always used by sequentially using the three or more satellites. When the inclined circular orbit satellite is in the operating state and the locus of the inclined circular orbit satellite is in the northern hemisphere or the southern hemisphere, the operating time of the inclined elliptic orbit satellite is the one that is located. Of the 2N (N ≧ 3 natural number) satellites, at least N are always in operation, and are selected from the above operating elliptical orbits and (N + 1) or more satellites on inclined circular orbits. Perform ground positioning using 4 satellites, and performs communication using satellites in inclined elliptical orbits that are above operation.
[0012]
In the high altitude orbit satellite communication positioning system of the invention according to claim 4, the eccentricity and inclination at which each satellite period on the orbit is two-thirds of the earth's rotation period and the ground locus of each satellite is equal. Inclined elliptical orbit satellite system comprising at least six inclined elliptical orbits having angles and one satellite arranged with an equal phase difference, totaling six or more, and each satellite period in orbit Are at least 2N (natural number of N ≧ 3) inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal in a period synchronized with the rotation of the earth. An inclined circular orbit satellite system having a total of 2N satellites arranged with a phase difference of 2N (N ≧ 3 natural number) at the southernmost or northernmost end of the ground trajectory of the inclined elliptical orbit One of the ground trajectory points with the higher satellite altitude and the center longitude of the ground trajectory of the tilted circular orbit are used in the same position, and the satellite with the higher satellite altitude is located at the southernmost or northernmost end of the tilted elliptical orbit satellite. At least one satellite corresponding to one of the ground trajectory points that coincides with the central longitude by sequentially using the six or more satellites as a predetermined time before and after the time passing through the center. Is always in operation and the trajectory of the inclined circular orbit satellite is in the northern hemisphere or the southern hemisphere where the center of the inclined elliptical orbit satellite is located is the operating time of the inclined circular orbit satellite. Among the 2N (N ≧ 3 natural number) satellites, at least N of them are always in operation, and from the above operating (N + 1) or more satellites on the inclined elliptical orbit and inclined circular orbit Selection To perform ground positioning using 4 satellites have, performs communication using satellites in inclined elliptical orbits that are above operation.
[0013]
The high altitude orbit satellite communication positioning system of the invention according to claim 5 has an eccentricity and an inclination angle at which each satellite period in the orbit is half the rotation period of the earth and the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising at least three inclined elliptical orbits, each of which is arranged at an equal phase difference, with a total of three or more satellites, and each satellite period in orbit is An equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal in a period synchronized with the rotation. 2 tilt circular orbit satellite systems each having 2N (N ≧ 3 natural number) spacecraft, and the southernmost or northernmost end of the ground trajectory of the tilted elliptical orbit Use the two ground trajectory points with the higher satellite altitude of the positions and the center longitudes of the ground trajectories of the two inclined circular orbits, and use either the southernmost or the northernmost satellite altitude of the inclined elliptical orbit satellite. At least one aircraft corresponding to each of the ground trajectory points that coincide with the central longitude by sequentially using the three or more satellites, with the predetermined time before and after the time passing through the higher one as the center. The operation of the inclined circular orbit satellite is when the satellite of the inclined circular orbit satellite is always in operation and the locus of the inclined circular orbit satellite is in the northern hemisphere or the southern hemisphere at the center of the operating time of the inclined elliptical orbit satellite. Each inclined ellipse in which at least N of the 2N (N ≧ 3 natural number) satellites are always in operation and the ground locus point and the central longitude coincide with each other. Performs ground positioning using four satellites selected from the (N + 1) or more operating satellites on the road and inclined circular orbits, and communicates using the operating satellites on the inclined elliptical orbit. Is.
[0014]
In the high altitude orbit satellite communication positioning system of the invention according to claim 6, the eccentricity and inclination at which each satellite period on the orbit is two-thirds of the earth's rotation period and the ground locus of each satellite is equal. Inclined elliptical orbit satellite system comprising at least six inclined elliptical orbits having angles and one satellite arranged with an equal phase difference, totaling six or more, and each satellite period in orbit Are at least 2N (natural number of N ≧ 3) inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal in a period synchronized with the rotation of the earth. The three inclined circular orbit satellite systems each having one satellite arranged with a phase difference of 2N (N ≧ 3 natural number) are connected to the southernmost or the most Use either the southernmost or the northernmost end of the above-mentioned inclined elliptical orbit satellite, using the three ground locus points with the higher satellite altitude of the end positions and the center longitudes of the above three inclined circular orbits. The operation time is a predetermined time before and after the time when the satellite altitude passes the higher one, and at least corresponding to each of the ground locus points corresponding to the center longitude by sequentially using the six or more satellites. A tilted circular orbit satellite when one satellite is always in operation and the locus of the tilted circular orbit satellite is in the northern hemisphere or the southern hemisphere at the center of the operating time of the tilted elliptical orbit satellite. Each of the 2N (N ≧ 3 natural number) satellites in a state where at least N of them are always in operation and the ground trajectory point and the central longitude coincide with each other. Performs ground positioning using four or more (N + 1) or more satellites operating on circular or tilted circular orbits, and communicates using satellites operating on tilted orbits. Is what you do.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is an explanatory diagram showing an example of ground trajectories of an inclined elliptical orbit satellite and an inclined circular orbit satellite synchronized with the rotation of the earth used in the high altitude inclined orbit satellite communication positioning system of Embodiment 1 of the present invention.
In the figure, 1 is a ground trajectory of an inclined circular orbit satellite synchronized with the earth's rotation, 1a to 1f is a satellite in an inclined circular orbit, 2 is a ground trajectory of an inclined elliptic orbit satellite synchronized with the earth's rotation, and 2a to 2c. Is a satellite in an inclined elliptical orbit.
Here, each satellite period on the orbit is a period synchronized with the rotation of the earth, and the phase is 120 degrees on three inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising three different satellites, one in total, and the tilted elliptical orbit where each satellite's period on the orbit is synchronized with the earth's rotation and the ground trajectory of each satellite is equal. An inclined circular orbit satellite system comprising a total of six satellites each having a phase difference of 60 degrees on six inclined circular orbits having a larger inclination angle, and the above-mentioned inclined elliptic orbit and inclined circular orbit The center longitude of the trajectory is used to match, and the above-mentioned tilted elliptical orbit satellite uses the southernmost or the northernmost end of the satellite at the higher altitude. The operating time is set so that at least one satellite is always operating by sequentially using the three satellites. The inclined circular orbit satellite has a locus of the inclined elliptical orbit satellite in the northern hemisphere or the southern hemisphere. The case where the center of the operation time is located is the operation time of the inclined circular orbit satellite, and at least three of the six satellites are always operating.
[0016]
Next, the operation will be described using an example in which the vicinity of Japan is serviced.
First, three satellites that draw the inclined elliptical orbit shown in FIG. 1 are arranged, and the arrangement of the satellites is adjusted so that the three satellites move on the ground locus 2 at equal intervals in time. Similarly, six satellites which draw the inclined circular orbit shown in FIG. 1 are arranged, and the arrangement of the satellites is adjusted so that the six satellites move on the ground locus 1 at equal intervals in time.
From the ground point in the service area near Japan, in the communication area centering on the northernmost end of the ground locus 2 of each inclined elliptical orbit satellite, at least one of the three satellites is always above a certain elevation angle. Appears at a viewing angle. Since the earth's rotation period is about 24 hours, the time interval of the three satellites is about 8 hours, and the satellites entering the viewing angle change every 8 hours. Communication with the satellite is always performed by activating the satellite that is always within the viewing angle and putting the remaining two satellites that are outside the viewing angle into a non-active waiting state.
Next, six tilted circular orbit satellites are always located in the northern and southern hemispheres, three of which are always active in the northern hemisphere. When these three active satellites are used for positioning, they are selected as the satellites constituting the bottom surface of the tetrahedron for determining the geometric error amount described with reference to FIG. A total of four satellites can be secured for the positioning system by selecting the active inclined elliptical orbit satellites that perform the communication as the satellites constituting the apexes of the tetrahedron.
[0017]
As described above, the first embodiment is configured only by the tilted orbit satellite system, and can perform two types of services of communication and positioning, thereby providing a system-specific service that is not influenced by other systems. it can. Further, in the inclined orbit satellite system of the first embodiment, by using an inclined orbit satellite having a high elevation angle in a high latitude region, positioning can be performed even in a case where a satellite at a low elevation angle cannot be observed as in an urban area. Enabling and providing a reliable service.
[0018]
Embodiment 2. FIG.
In the first embodiment described above, communication and positioning are performed using the minimum number of satellites, but an embodiment in which positioning is performed with higher accuracy will be described below.
FIG. 2 is an explanatory diagram showing examples of the ground trajectories of the tilted elliptical orbit satellite and the tilted circular orbit satellite synchronized with the rotation of the earth used in the high altitude tilted orbit satellite communication positioning system of Embodiment 2 of the present invention. . In the figure, 1 is a ground trajectory of a tilted circular orbit satellite synchronized with the earth, 1a ′ to 1h ′ is a satellite in a tilted circular orbit, 2 is a ground trajectory of a tilted elliptical orbit satellite synchronized with the earth, and 2a ′ to 2d ′. Is a satellite in an inclined elliptical orbit. These satellites draw a ground locus similar to that described in the first embodiment.
Here, each satellite period in orbit is a period that synchronizes with the rotation of the earth, and each of the above-mentioned satellite's ground trajectories is equal on at least three or more inclined elliptical orbits having an eccentricity and an inclination angle. A satellite with a tilted elliptical orbital satellite with three or more satellites arranged with a phase difference of one percent, and a period in which each satellite period in orbit is synchronized with the earth's rotation. A total of 2N satellites, each of which is arranged with an equal phase difference on at least 2N (N ≧ 4 natural number) inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the trajectories are equal, are placed. N ≧ 4 (natural number) machine and a tilted circular orbit satellite system using the tilted elliptical orbit and the central longitude of the ground trajectory of the tilted circular orbit aligned with each other. At least one satellite is always in operation by using the above three or more satellites sequentially as the operation time is the predetermined time around the time of passing the higher satellite altitude of the northernmost one. The tilted circular orbit satellite is located in the northern hemisphere or the southern hemisphere where the center of the tilted elliptical orbit satellite is located. This is an example in which at least N of the satellites of ≧ 4 are always operating.
[0019]
Next, the operation will be described.
By making the number of satellites that draw the ground trajectory 1 of tilted circular orbit satellites synchronized with the rotation of the earth to be 8 or more (Fig. 2 shows 8 examples), 4 or more satellites always appear in the northern hemisphere. It becomes. Therefore, when selecting the satellites constituting the tetrahedron for determining the geometric error amount described with reference to FIG. 9, the optimum three of the four or more satellites can be selected. Further, the number of satellites that draw the ground locus 2 of the inclined elliptical orbit satellite synchronized with the rotation of the earth is four or more. The greater the number of satellites, the higher the elevation angle of the satellites as seen from the ground, and the less the fluctuations of the satellites in the latitude and longitude directions. Furthermore, the probability of satellites present at the zenith of the ground point increases. In addition, it is possible to select the satellite that constitutes the optimum vertex of the tetrahedron corresponding to the bottom surface of the tetrahedron formed by the satellite that draws the ground locus 1 of the inclined circular orbit satellite that is synchronized with the rotation of the earth. .
[0020]
As described above, in the second embodiment, by increasing the number of satellites that draw two types of ground trajectories, it is possible to select the optimum satellite that constitutes the tetrahedron used for positioning. More accurate positioning than shown can be performed.
[0021]
Embodiment 3 FIG.
FIG. 3 shows the ground trajectories of the inclined circular orbit satellite synchronized with the earth rotation used in the high altitude inclined orbit satellite communication positioning system according to the third embodiment of the present invention and the inclined elliptic orbit satellite whose period is half of the earth rotation period. It is explanatory drawing which shows an example.
In the figure, 1 is a ground trajectory of a tilted circular orbit satellite synchronized with the earth's rotation, 1a to 1f is a satellite in a tilted circular orbit, 3 is a ground trajectory of a tilted elliptical orbit satellite whose period is half of the earth's rotation period. Reference numerals 3a to 3c denote satellites in inclined elliptical orbits.
Here, each satellite period on the orbit is half of the earth's rotation period, and each of the above-mentioned satellite's ground trajectories is equally divided into at least three or more inclined elliptical orbits having an eccentricity and an inclination angle. Inclined elliptical orbit satellite system with a total of three or more satellites arranged with a phase difference of 1 and the ground trajectory of each of the satellites in a period in which each satellite period in orbit is synchronized with the rotation of the earth. One satellite arranged at an equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the above-mentioned inclined elliptical orbits having the same 2N (N A tilted circular orbit satellite system equipped with a ≧ 3 natural number) and one of the ground trajectory points with the higher satellite altitude among the most southern or northernmost positions of the ground trajectory of the tilted elliptical orbit. The center longitude of the ground trajectory of the circular orbit is used to match, and the operation time is a predetermined time around the time when the above-mentioned tilted elliptical orbit satellite passes the higher satellite height, whichever is the southernmost or northernmost. By using the three or more satellites sequentially, at least one satellite corresponding to one of the ground locus points that coincides with the central longitude is always in operation, and the locus of the inclined circular orbit satellite Is the one in which the center of the operation time of the inclined elliptical orbit satellite is located in the northern hemisphere or the southern hemisphere, and the operation time of the inclined circular orbit satellite is defined as at least N of the 2N (N ≧ 3 natural number) satellites. This is an example in which the machine is always operating.
[0022]
Next, the operation will be described using the case where service is provided in the vicinity of Japan and the Atlantic Ocean illustrated in FIG.
First, three satellites that draw the inclined elliptical orbit shown in FIG. 3 are arranged, and the arrangement of the satellites is adjusted so that these three satellites move on the ground locus 3 at equal intervals in time. Similarly, six satellites which draw the inclined circular orbit shown in FIG. 3 are arranged, and the arrangement of the satellites is adjusted so that these six satellites move on the ground locus 1 at equal intervals in time.
Here, in the case of FIG. 3, when a far point (position with the highest satellite altitude) occurs at 140 degrees east longitude, a far point also occurs at a position 40 degrees west, 180 degrees away from there. The satellites themselves have returned to the same position after 12 hours in the two far points, but since the earth's rotation period is 24 hours, far points are generated at a position shifted by 180 degrees in longitude on the ground trajectory. That is, the three satellites in the inclined elliptical orbit draw the same trajectory, and when they make two rounds of the earth, they reach the highest satellite altitude on the ground at the same northernmost point and 180 degrees away from the longitude.
The satellite altitude is derived from the relationship between the satellite and the earth's gravity, etc., but the satellite altitude decreases as the period becomes shorter. Decrease.
In addition, if one of the two northernmost positions separated by 180 degrees in longitude is near Japan, the other is located on the Atlantic Ocean.
At the ground point in the service area near Japan, at least one of the three satellites always has a field of view above a certain elevation angle in the communication area centered on the northernmost end of the ground trajectory of each inclined elliptical orbit satellite. Appears at the corner. The time interval between the three satellites is about 8 hours, and the satellites entering the viewing angle change every 8 hours (or 8 hours per aircraft when always serviced with 3 aircraft). Communication with the satellite is always performed by activating the satellite that is always within the viewing angle and putting the remaining two satellites that are outside the viewing angle into a non-active waiting state. Six tilted circular orbit satellites are used for positioning in the same manner as in the first embodiment. Further, for satellites in inclined elliptical orbits that are near the northernmost end of the ground trajectory on the other Atlantic Ocean, it is possible to provide communication services for this region.
[0023]
As described above, also in the third embodiment, two types of services, communication and positioning, can be performed, and thereby a system-specific service that is not influenced by other systems can be performed. Further, in this embodiment, by using an inclined elliptical orbit whose period is half of the earth's rotation period, the communication has a short delay time in communication and is efficient in two regions 180 degrees apart from each other. Service can be performed.
[0024]
Embodiment 4 FIG.
FIG. 4 shows a tilted circular orbit satellite synchronized with the rotation of the earth used in the high altitude orbit satellite communication positioning system according to the fourth embodiment of the present invention and a tilted elliptical orbit satellite whose period is two-thirds of the rotation period of the earth. It is explanatory drawing which shows the example of a ground locus | trajectory.
In the figure, 4 is a ground trajectory of an inclined elliptical orbit satellite whose period is two-thirds of the earth's rotation period, and 4a to 4f are satellites on the inclined elliptical orbit.
Here, each satellite period in orbit is at least two thirds of the earth's rotation period, and at least six inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal, Each tilted elliptical orbit satellite system with six or more satellites arranged with equal phase difference, and each satellite in the orbit is synchronized with the Earth's rotation. The total number of satellites arranged with an equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the above-mentioned inclined elliptical orbit where the ground trajectories are equal. A tilted circular orbit satellite system equipped with 2N (N ≧ 3 natural number) machine is connected to one of the ground trajectory points with the higher satellite altitude among the most southern or northernmost positions of the ground trajectory of the tilted elliptical orbit. The center longitude of the ground trajectory of the inclined circular orbit is used to match, and the operating time is a predetermined time around the time when the above-mentioned inclined elliptical orbit satellite passes the higher satellite altitude, whichever is the southernmost or northernmost. By sequentially using the six or more satellites, at least one satellite corresponding to one of the ground locus points that coincides with the central longitude is always in operation, and the inclined circular orbit satellite In the northern hemisphere or the southern hemisphere, when the center of the operation time of the tilted elliptical orbit satellite is located, the operation time of the tilted circular orbit satellite is defined as the operation time of at least the 2N (N ≧ 3 natural number) satellites. This is an example in which N machines are always operating.
[0025]
Next, the operation will be described using the case where service is provided in the vicinity of Japan, North America, and the Mediterranean Sea illustrated in FIG.
First, six satellites that draw the ground locus 4 of the inclined elliptical orbit satellite whose period shown in FIG. 4 is two-thirds of the earth's rotation period are arranged, and these six satellites are inclined elliptical orbit at equal intervals in time. The arrangement of the satellites is adjusted to move on the trajectory. Further, six satellites that draw the ground trajectory 1 of the inclined circular orbit satellite synchronized with the rotation of the earth shown in FIG. 4 are arranged so that these six satellites move on the inclined circular orbit locus at equal intervals in time. The satellite arrangement is adjusted.
The six satellites 4a to 4f in the inclined elliptical orbit each draw the same locus, and when they make three rounds of the earth, the highest satellite altitude is located on the ground at the same northernmost point and 120 degrees away from the longitude. . Further, since the satellite altitude is lower than that in the first embodiment, the delay time during communication is reduced. If one of the three northernmost positions separated by 120 degrees in longitude is located near Japan, the other two are located near North America and the Mediterranean Sea. At the ground point in the service area near Japan, at least one of the six satellites in the communication area centered on the northernmost end of the ground locus of each inclined elliptical orbit satellite always has a field of view above a certain elevation angle. Appears at the corner. The time interval of the six satellites is about 8 hours, and the satellites entering the viewing angle change every 8 hours. Communication with the satellite is always performed by activating the satellite that is always within the viewing angle and putting the remaining two satellites that are outside the viewing angle into a non-active waiting state. Six tilted circular orbit satellites are used for positioning in the same manner as in the first embodiment. Further, for satellites in inclined elliptical orbits that are near the northernmost end of the ground locus in the vicinity of North America and the Mediterranean Sea other than near Japan, it is possible to provide communication services for this region.
[0026]
As described above, also in the fourth embodiment, two types of services, communication and positioning, can be performed, and thereby a system-specific service that is not influenced by other systems can be performed. Also, in this embodiment, by using an inclined elliptical orbit whose period is two-thirds of the earth's rotation period, there is little delay time for communication and three distances 120 degrees apart Efficient service can be provided to the region.
[0027]
In the third and fourth embodiments, the period of the inclined elliptical orbit satellite is changed to an appropriate one, and the ground of the inclined circular orbit satellite whose center longitude coincides with one of the northernmost positions of the ground locus. By arranging the trajectory, an efficient service can be provided to a plurality of areas in the same manner as described above.
[0028]
Embodiment 5 FIG.
5 and 6 are explanatory diagrams showing examples of the ground trajectories of the inclined circular orbit satellite and the inclined elliptical orbit satellite used in the high altitude inclined orbit satellite communication positioning system according to the fifth embodiment of the present invention.
FIG. 5 is an explanatory diagram showing an example of a ground trajectory of a tilted circular orbit satellite synchronized with the rotation of the earth and a tilted elliptical orbit satellite whose period is half of the rotation period of the earth.
In the figure, 1 and 11 are the ground trajectories of the inclined circular orbit satellites synchronized with the earth's rotation, 1a to 1f are the satellites on the inclined circular orbit, and 3 is the inclined elliptical orbit satellite whose period is half of the earth's rotation period. The ground trajectories 3a to 3c are satellites in an inclined elliptical orbit.
Here, each satellite period on the orbit is half of the earth's rotation period, and each of the above-mentioned satellite's ground trajectories is equally divided into at least three or more inclined elliptical orbits having an eccentricity and an inclination angle. Inclined elliptical orbit satellite system with a total of 3 or more satellites arranged with a phase difference of 1 and a ground trajectory of each of the above satellites with a period in which each satellite period in orbit is synchronized with the rotation of the earth. One satellite arranged at an equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the above-mentioned inclined elliptical orbits having the same 2N (N ≧ 3 natural number) two inclined circular orbit satellite systems, and two of the ground locus points with the higher satellite altitude among the southernmost and northernmost positions of the ground locus of the inclined elliptical orbit. The center longitudes of the ground trajectories of the two inclined circular orbits are used so as to coincide with each other, and the predetermined elliptical orbit of the inclined elliptical orbit satellite before and after centering on the time when the satellite altitude is higher is passed. By using the above three or more satellites sequentially as the operating time, at least one satellite corresponding to each of the ground trajectory points that coincide with the central longitude is always operating, and the tilt circle The trajectory of the orbiting satellite is in the northern hemisphere or the southern hemisphere and the center of the operating time of the inclined elliptical orbiting satellite is the operating time of the inclined circular orbiting satellite, and the satellite of the above 2N (N ≧ 3 natural number) In this example, at least N machines are always operating.
FIG. 6 is an explanatory diagram showing an example of a ground trajectory of a tilted circular orbit satellite synchronized with the rotation of the earth and a tilted elliptical orbit satellite whose period is two-thirds of the rotation period of the earth.
In the figure, 1 and 12a, 12b are ground trajectories of inclined circular orbit satellites synchronized with the rotation of the earth, 4 is a ground trajectory of inclined elliptic orbit satellites whose period is two-thirds of the earth's rotation period, and 4a to 4f are A satellite in an inclined elliptical orbit.
In each figure, the ground trajectory 1 of the tilted circular orbit satellite synchronized with the rotation of the earth is the trajectory of the tilted circular orbit in which the central longitude coincides with the vicinity of Japan as described in the first embodiment, etc. Reference numerals 11, 12 a, and 12 b are trajectories of the tilted circular orbit satellite in which the central longitude coincides with those other than the vicinity of Japan among the plurality of northernmost positions of the trajectory of the tilted elliptical orbit satellite.
Here, each satellite period in orbit is at least two thirds of the earth's rotation period, and at least six inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal, Each tilted elliptical orbit satellite system with a total of 6 or more satellites arranged with equal phase difference of each satellite, and each of the above satellites in a period in which each satellite period in orbit is synchronized with the earth's rotation. The total number of satellites arranged with an equal phase difference on at least 2N (N ≧ 3 natural number) inclined circular orbits having a larger inclination angle than the above-mentioned inclined elliptical orbit where the ground trajectories are equal. 3 inclined circular orbit satellite systems equipped with 2N (N ≧ 3 natural number) machines are connected to the ground locus point 3 having the higher satellite altitude among the most southern or northernmost positions of the ground locus of the inclined elliptical orbit. And the center longitudes of the ground trajectories of the three inclined circular orbits, respectively, and a predetermined value before and after centering on the time when the inclined elliptical orbit satellite passes the higher satellite altitude, which is the southernmost end or the northernmost end. The above-mentioned time is used as the operating time, and at least one satellite corresponding to each of the ground trajectory points corresponding to the central longitude is always operating by sequentially using the six or more satellites. The case where the locus of the circular orbit satellite is in the northern hemisphere or the southern hemisphere is located at the center of the operation time of the inclined elliptical orbit satellite is defined as the operation time of the inclined circular orbit satellite, and the 2N (N ≧ 3 natural number) aircraft In this example, at least N of the satellites are always in operation.
[0029]
Here, FIG. 5 shows an example of service near Japan and the Atlantic Ocean, and FIG. 6 shows an example of service near Japan and North America and the Mediterranean Sea.
For each of the cases shown in FIGS. 5 and 6, communication is performed by configuring the tilted circular orbit satellites in regions other than Japan, such as on the Atlantic Ocean or near North America and the Mediterranean Sea. A unique positioning system independent of the system can be configured.
[0030]
As described above, when using a tilted elliptical orbit satellite whose period is half or two thirds of the earth's rotation period, the center longitude is set at each position for all positions where the ground locus is the northernmost end. By arranging the matched inclined circular orbit satellites, it is possible to provide two types of services, communication and positioning, for the area centered on each position.
[0031]
In the fifth embodiment, the period of the inclined elliptical orbit satellite is changed to an appropriate one, and a plurality of inclined circular orbit satellites whose center longitudes coincide with the desired plural northernmost positions of the ground locus are used. By arranging the ground locus, two types of services, communication and positioning, can be performed for a plurality of areas in the same manner as described above.
[0032]
【The invention's effect】
As described above, according to the present invention, the system is composed only of a high-altitude inclined orbit satellite system, and can perform two types of services, communication and positioning, thereby providing a system-specific service that is not influenced by other systems. be able to. In addition, by using tilted orbit satellites with a high elevation angle in the high latitude region of the Northern Hemisphere or Southern Hemisphere, positioning is possible even when satellites with a low elevation angle cannot be observed, such as in urban areas, and a reliable service. It can be performed.
[0033]
Further, according to the invention of claim 2, the optimum satellite constituting the tetrahedron used for positioning is selected by increasing the number of satellites that draw two kinds of ground trajectories of the high altitude inclined orbit satellite system. And more accurate positioning can be performed.
[0034]
Further, according to the invention of claim 3, by using an inclined elliptical orbit whose period is half of the earth's rotation period, the communication has a short delay time in communication, and two regions separated by 180 degrees in longitude. Can provide efficient service.
[0035]
In addition, according to the invention of claim 4, by using an inclined elliptical orbit whose period is two-thirds of the earth's rotation period, the delay time at the time of communication is small, and the longitude is 120 degrees apart. Efficient services can be provided to three regions.
[0036]
According to the invention of claim 5 or claim 6, when using an inclined elliptical orbit satellite whose period is half or two thirds of the earth's rotation period, By placing inclined circular orbit satellites whose center longitudes coincide with each position for all positions with the highest satellite altitude among the northernmost positions, communication and communication with the area centered on each position Two types of positioning services can be performed.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing examples of ground trajectories of an inclined elliptical orbit satellite and an inclined circular orbit satellite synchronized with the rotation of the earth used in the high altitude inclined orbit satellite communication positioning system according to Embodiment 1 of the present invention;
FIG. 2 is an explanatory diagram showing an example of ground trajectories of an inclined elliptic orbit satellite and an inclined circular orbit satellite synchronized with the rotation of the earth used in the high altitude inclined orbit satellite communication positioning system according to the second embodiment of the present invention;
FIG. 3 is a ground trajectory of a tilted circular orbit satellite synchronized with the rotation of the earth used in the high altitude tilted orbit satellite communication positioning system of Embodiment 3 of the present invention and a tilted elliptical orbit satellite whose period is half of the rotation period of the earth. It is explanatory drawing which shows the example of.
FIG. 4 is a tilted circular orbit satellite synchronized with the rotation of the earth used in the high altitude tilted orbit satellite communication positioning system according to the fourth embodiment of the present invention, and a tilted elliptical orbit satellite whose period is two-thirds of the rotation period of the earth. It is explanatory drawing which shows the example of the ground locus | trajectory.
FIG. 5 is an explanatory diagram showing examples of ground trajectories of inclined circular orbit satellites and inclined elliptical orbit satellites used in the high altitude inclined orbit satellite communication positioning system according to Embodiment 5 of the present invention; It is explanatory drawing which shows the example of the ground locus | trajectory of an orbiting satellite and a slant elliptical orbiting satellite whose period is a half of the rotation period of the earth.
6 is an explanatory diagram showing examples of ground trajectories of inclined circular orbit satellites and inclined elliptical orbit satellites used in the high altitude inclined orbit satellite communication positioning system according to Embodiment 5 of the present invention, and is an inclined circle synchronized with the rotation of the earth. FIG. It is explanatory drawing which shows the example of the ground locus | trajectory of an orbiting satellite and a slant elliptical orbiting satellite whose period is 2/3 of the earth's rotation period.
FIG. 7 is an explanatory diagram showing an example of a satellite ground trajectory in a conventional inclined orbit satellite communication positioning system;
FIG. 8 is an explanatory diagram showing the positional relationship between a satellite and a ground point used when positioning an arbitrary ground point using a satellite;
FIG. 9 is an explanatory diagram showing a configuration of a tetrahedron for determining a geometric error amount;
[Explanation of symbols]
1. Ground trajectory of tilted circular orbit satellites synchronized with the earth's rotation, 1a to 1f Satellites on the inclined circular orbits, 1a 'to 1h' Satellites on the inclined circular orbits, 2 Inclined elliptical orbit satellites synchronized with the earth's rotation 2a-2c is a satellite in a slanted elliptical orbit, 2a'-2d 'a satellite in a slanted elliptical orbit, 3 a ground locus of a slanted elliptical orbit satellite whose period is half of the earth's rotation period, 3a- 3c A satellite in a tilted elliptical orbit, 4 A ground trajectory of a tilted elliptical orbit satellite whose period is two-thirds of the Earth's rotation period, 4a to 4f A satellite in a tilted elliptical orbit, 5 A ground trajectory of a tilted circular orbit satellite 5a-5c satellite, 6 earth, 71-74 satellite, 8 user position, 91-94 unit vector from user position to each satellite direction, 10 tetrahedron, 11 tilted circular orbit satellite synchronized with earth rotation Ground locus, 12a, 1 The ground trajectory of inclination circular orbit satellite to be synchronized with the rotation of the earth b.

Claims (6)

Each satellite period in orbit is synchronized with the earth's rotation, and the satellites whose phases are 120 degrees different from each other on three inclined elliptical orbits having the eccentricity and inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system with three aircraft, one by one,
Each of the satellite periods on the orbit is synchronized with the rotation of the earth, and the phase is 60 on each of the six inclined circular orbits having a larger inclination angle than the inclined elliptical orbit where the ground trajectories of the respective satellites are equal. A tilted circular orbit satellite system with a total of 6 satellites, one each at different degrees,
Use the tilted elliptical orbit and the center longitude of the ground trajectory of the tilted circular orbit to match,
By using the three satellites in sequence, the operation time is 8 hours in total, 4 hours before and after the time of passing the higher altitude of the satellite at the southernmost or northernmost end of the inclined elliptical orbit satellite. At least one satellite is always in operation,
When the locus of the inclined circular orbit satellite is located in the northern hemisphere or the southern hemisphere at the center of the operating time of the inclined elliptical orbit satellite, the operation time of the inclined circular orbit satellite is defined, and at least 3 of the six satellites. The machine is in constant operation,
The ground positioning is performed using a total of four satellites on the above-described inclined elliptical orbit and inclined circular orbit, and communication is performed using the above-described satellites on the inclined elliptical orbit. Advanced inclined orbit satellite communication positioning system. Each satellite period in orbit is synchronized with the earth's rotation, and each of the satellites on the orbit has at least three or more inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories are equal. A tilted elliptical orbit satellite system comprising one or more satellites arranged in phase difference, a total of three or more,
An inclination circle of at least 2N (N ≧ 4 natural number) having a larger inclination angle than the inclined elliptical orbit where each satellite period in orbit is synchronized with the rotation of the earth and the ground trajectory of each satellite is equal. A tilted circular orbit satellite system having a total of 2N (N ≧ 4 natural number) satellites, one satellite arranged at equal phase difference in orbit,
Use the tilted elliptical orbit and the center longitude of the ground trajectory of the tilted circular orbit to match,
By using the above three or more satellites in sequence, the operation time is a predetermined time before and after the time when the inclined elliptical orbit satellite passes the higher satellite altitude of the southernmost end or the northernmost end. One satellite is always in operation,
When the locus of the inclined circular orbit satellite is in the northern hemisphere or the southern hemisphere, the operation time of the inclined elliptic orbit satellite is located at the center of the inclined elliptic orbit satellite, and the operation time of the inclined circular orbit satellite is 2N (N ≧ 4 natural number). At least N of the satellites are always in operation,
Ground positioning is performed using four satellites selected from the above-described tilted elliptical orbit and (N + 1) or more satellites on the tilted circular orbit, and the above-described satellites on the tilted elliptical orbit are used. High altitude orbit satellite communication positioning system characterized by communication. Each satellite period in orbit is half of the Earth's rotation period, and the above-mentioned satellite's ground trajectories have the same eccentricity and inclination angle. Inclined elliptical orbit satellite system with 3 or more satellites arranged in 1 each,
An inclination circle of at least 2N (N ≧ 3 natural number) having a larger inclination angle than the inclined elliptical orbit in which each satellite period in orbit is synchronized with the rotation of the earth and the ground trajectories of the respective satellites are equal. A tilted circular orbit satellite system comprising a total of 2N (N ≧ 3 natural number) satellites, one satellite arranged at equal phase difference on orbit,
Use one of the ground trajectory points with the higher satellite altitude in the southernmost or northernmost position of the ground trajectory of the tilted elliptical orbit and the center longitude of the ground trajectory of the tilted circular trajectory,
By using the three or more satellites in sequence, the operation time is a predetermined time around the time when the inclined elliptical orbit satellite passes through the highest satellite altitude of the southernmost or the northernmost. At least one satellite corresponding to one of the ground trajectory points that coincides with the central longitude is always in operation,
When the locus of the inclined circular orbit satellite is located in the northern hemisphere or the southern hemisphere where the center of the inclined elliptical orbit satellite is located, the operation time of the inclined circular orbit satellite is defined as 2N (natural number of N ≧ 3). At least N of the satellites are always in operation,
Ground positioning is performed using four satellites selected from the above-described tilted elliptical orbit and (N + 1) or more satellites on the tilted circular orbit, and the above-mentioned satellites on the tilted elliptical orbit are used. High altitude orbit satellite communication positioning system characterized by communication. Each satellite period in orbit is two-thirds of the earth's rotation period, and each satellite is divided equally on at least six inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising a total of 6 or more satellites arranged with a phase difference of
An inclination circle of at least 2N (N ≧ 3 natural number) having a larger inclination angle than the inclined elliptical orbit in which each satellite period in orbit is synchronized with the rotation of the earth and the ground trajectories of the respective satellites are equal. A tilted circular orbit satellite system comprising a total of 2N (N ≧ 3 natural number) satellites, one satellite arranged at equal phase difference on orbit,
Use one of the ground trajectory points with the higher satellite altitude in the southernmost or northernmost position of the ground trajectory of the tilted elliptical orbit and the center longitude of the ground trajectory of the tilted circular trajectory,
By using the above six or more satellites in sequence, the operation time is a predetermined time around the time when the inclined elliptical orbit satellite passes through the highest satellite altitude of the southernmost or northernmost end. At least one satellite corresponding to one of the ground trajectory points that coincides with the central longitude is always in operation,
When the locus of the inclined circular orbit satellite is located in the northern hemisphere or the southern hemisphere where the center of the inclined elliptical orbit satellite is located, the operation time of the inclined circular orbit satellite is defined as 2N (natural number of N ≧ 3). At least N of the satellites are always in operation,
Ground positioning is performed using four satellites selected from the above-described tilted elliptical orbit and (N + 1) or more satellites on the tilted circular orbit, and the above-mentioned satellites on the tilted elliptical orbit are used. High altitude orbit satellite communication positioning system characterized by communication. Each satellite period in orbit is half of the Earth's rotation period, and the above-mentioned satellite's ground trajectories have the same eccentricity and inclination angle. Inclined elliptical orbit satellite system with 3 or more satellites arranged in 1 each,
An inclination circle of at least 2N (N ≧ 3 natural number) having a larger inclination angle than the inclined elliptical orbit in which each satellite period in orbit is synchronized with the rotation of the earth and the ground trajectories of the respective satellites are equal. Two inclined circular orbit satellite systems each having a total of 2N (N ≧ 3 natural number) satellites, each of which is arranged in an orbit with an equal phase difference,
Of the ground locus of the above-mentioned inclined elliptical orbit, use two of the ground locus points with the higher satellite altitude in the southernmost or northernmost position of the ground locus and the center longitudes of the above-mentioned two inclined circular orbits.
By using the three or more satellites in sequence, the operation time is a predetermined time around the time when the inclined elliptical orbit satellite passes through the highest satellite altitude of the southernmost or the northernmost. At least one satellite corresponding to each of the ground trajectory points that coincides with the central longitude is always in operation,
When the locus of the inclined circular orbit satellite is located in the northern hemisphere or the southern hemisphere where the center of the inclined elliptical orbit satellite is located, the operation time of the inclined circular orbit satellite is defined as 2N (natural number of N ≧ 3). At least N of the satellites are always in operation,
Ground positioning is performed using four satellites selected from the (N + 1) or more satellites operating on the inclined elliptical orbit and the inclined circular orbit in which the ground locus point and the central longitude coincide. A high altitude orbit satellite communication positioning system, which performs communication using a satellite in a tilted elliptical orbit in operation. Each satellite period in orbit is two-thirds of the earth's rotation period, and each satellite is divided equally on at least six inclined elliptical orbits having an eccentricity and an inclination angle at which the ground trajectories of the respective satellites are equal. A tilted elliptical orbit satellite system comprising a total of 6 or more satellites arranged with a phase difference of
An inclination circle of at least 2N (N ≧ 3 natural number) having a larger inclination angle than the inclined elliptical orbit in which each satellite period in orbit is synchronized with the rotation of the earth and the ground trajectories of the respective satellites are equal. Three inclined circular orbit satellite systems each having a total of 2N (N ≧ 3 natural number) satellites, one satellite arranged at equal phase difference in orbit,
Of the ground locus of the above-mentioned inclined elliptical orbit, use the three most recent ground locus points with the higher satellite altitude and the center longitude of the ground locus of the above three inclined circular orbits.
By using the above six or more satellites in sequence, the operation time is a predetermined time around the time when the inclined elliptical orbit satellite passes through the highest satellite altitude of the southernmost or northernmost end. At least one satellite corresponding to each of the ground trajectory points that coincides with the central longitude is always in operation,
When the locus of the inclined circular orbit satellite is located in the northern hemisphere or the southern hemisphere where the center of the inclined elliptical orbit satellite is located, the operation time of the inclined circular orbit satellite is defined as 2N (natural number of N ≧ 3). At least N of the satellites are always in operation,
Ground positioning is performed using four satellites selected from the (N + 1) or more satellites operating on the inclined elliptical orbit and the inclined circular orbit in which the ground locus point and the central longitude coincide. A high altitude orbit satellite communication positioning system, which performs communication using a satellite in a tilted elliptical orbit in operation.

Images