RU2755019C2 - Method for constructing space relay and communication system - Google Patents

Abstract

FIELD: communication.SUBSTANCE: invention relates to the field of radio communication using relay satellites in highly elliptical and geostationary orbits and is intended to be primarily used in space relay and communication systems. To realise the described result, at least two relay satellites in a geostationary orbit are introduced into the orbital group of the space relay and communication system, wherein the angle separation between said satellites is set close to 180°, each of said relay satellites is equipped with retargetable radio frequency or optical range antennas and associated repeaters providing high-speed information exchange with space subscribers, the relay satellites in highly elliptical and geostationary orbits are equipped with retargetable antennas and associated repeaters for communication between the relay satellites in highly elliptical orbits and the relay satellites in the geostationary orbit providing low-speed information exchange between space and earth subscribers and central earth stations when the relay satellites in highly elliptical orbits are located outside the visibility area of the central earth stations, current control of the spatial position of the communication lines between the relay satellites is executed on all relay satellites, said communication line with the smallest reach is selected and information exchange thereon is excluded when said line is obscured by the Earth or the adjacent atmospheric layer.EFFECT: developing a method for constructing a space relay and communication system, reducing the coverage of inter-satellite communication antennas and providing a possibility of continuous operation of inter-satellite communication lines.1 cl, 1 dwg

Description

The alleged invention relates to the field of radio communication using repeater satellites (SR) in highly elliptical and geostationary orbits and is intended for preferential use in space relay systems (RRS) and communications, the subscribers of which are earth and space stations, including those operating in a common wavelength range ...

A known method of building a space relay and communication system based on geostationary satellites Inmarsat-4 (USA. A joint product of Inmarsat and AVI - a satellite data relay system - comes out of the shadows after many months of secret tests in space // "Rocket and space technology." 2017. No. 8-9, pp. 15-18). The essence of this method lies in the fact that Inmarsat-4 satellites, equipped with a large-sized multibeam L-band antenna with an aperture of 9 x 12 m and providing personal mobile communication with low-energy terrestrial subscribers of the "telephone receiver" type with omnidirectional antennas (Kopik A. The heaviest commercial communication satellite // Cosmonautics News. 2005. No. 5, pp. 8-10) will additionally be used to control low-energy space subscribers in low Earth orbits. Such subscribers include objects of rocket and space technology, on which directional antennas (launch vehicles, upper stages) cannot be structurally implemented, as well as low-orbit spacecraft that have lost their orientation, whose command-measuring system switches to operation through omnidirectional antennas in emergency situations. ...

Currently existing personal mobile communications satellites, similar to the Inmarsat-4 satellite (Thuraya, Garuda, AlphaSat-I-XL, TerreStar, etc.) with antennas over 12 m in diameter, also have the ability to serve low-energy space subscribers. At the same time, on the currently operated relay satellites of specialized space relay systems (TDRSS, SDS, Luch, etc.), antennas with a diameter of 3 to 4.5 m are used to communicate with space subscribers, therefore, the use of satellites for this purpose of the Inmarsat-4 type with an antenna diameter of more than 12 m, it allows an order of magnitude to increase the energy potential (and, accordingly, the throughput) of communication lines with space users or, on the other hand, to reduce the power of onboard transmitters of space users by the same amount.

The disadvantage of the considered method in relation to the territory of Russia is that communication with geostationary satellites on it is possible at relatively low elevation angles (no more than 30 °), which leads to large signal losses during their propagation through the earth's atmosphere and through the regions where atmospheric precipitation occurs. In addition, at low elevation angles, the probability of signal blocking by natural heights and buildings increases, signal absorption by tree foliage increases, etc. Finally, the Arctic regions do not fall into the field of view of geostationary satellites, which is also of no small importance for Russia.

Elimination of the listed disadvantages of communication satellites in the geostationary orbit (GSO) can be achieved by using satellites in inclined highly elliptical orbits (HEO), for example, of the "Molniya" type, the primacy in the development of which belongs to our country. A satellite in such an orbit with an apogee in the Northern Hemisphere is capable of covering the entire territory of Russia, providing communication with any points in the country through a single relay through a satellite. When using geostationary satellites, this is not possible, since at least two such satellites are required to cover the entire territory of Russia. At the same time, communication via a satellite on the HEO can be carried out at elevation angles of at least 40 ° (up to zenith angles), which significantly reduces the above problems in the propagation of a radio signal.

There is a known method of constructing a DAC designed for communication with low-energy terrestrial and space subscribers, based on geosynchronous SRs, circulating via VEO with longitudes of ascending nodes spaced 120 ° apart, and equipped with large-sized multi-beam antennas (RF Patent No. 2366086), which is selected as a prototype. To ensure continuous communication on the territory of Russia, such a space system must include 3 successively replacing SRs, the duration of the active operation section of which is no more than one third of the orbital period (for daily orbits). Since the service of space subscribers can be carried out at any point in the near-earth space at altitudes up to about 20 thousand km, and the SR on VEO in some periods of time may be out of the visibility zone of the central earth control and communication stations on the territory of Russia, then in this system through inter-satellite radio links communication is maintained between the SR located in the radio visibility zone of the central earth stations with the rest of the SRs located outside the specified zone.

The disadvantage of this system is that, firstly, due to the high dynamics of the mutual movement of the SR on the HEO, the spatial position of the inter-satellite radio lines changes over a very wide range, and this imposes high requirements on the sector of the survey of antennas for inter-satellite communication, which are structurally difficult to implement. Secondly, at certain points in time, there is a disruption in the operation of inter-satellite lines due to their eclipse by the Earth or the adjacent atmospheric layer.

For the claimed method, the following general essential features have been identified: A method for constructing a space relay and communication system, in which information exchange between low-energy earth and space subscribers and central earth stations is carried out through relay satellites in highly elliptical orbits containing multi-beam antennas and associated repeaters.

The technical problem of the proposed invention is the development of a method for constructing a space relay and communication system, providing a reduction in the coverage sectors of antennas for inter-satellite communication and the possibility of continuous operation of inter-satellite communication lines.

This problem is solved by the fact that at least two SRs in the GSO are introduced into the orbital grouping of the said space relay and communication system, the angular separation between which is set close to 180 °, each SR in the GSO is equipped with steerable antennas of the radio frequency or optical range and associated with them with repeaters, with the help of which they carry out information exchange with high-energy space subscribers, SRs on HEO and GSO are equipped with retargetable antennas and associated repeaters for communication between SRs on HEO and GSO, with the help of which they carry out information exchange between low-energy space and terrestrial subscribers and central earth stations during the period when the SR is on HEO outside the visibility zone of central earth stations, on all SRs they carry out current control of the spatial position of communication lines between the SR on HEO and GSO, select the specified communication line with the shortest length and exclude information exchange along it during its eclipse by the Earth or the adjacent atmospheric layer.

The alleged invention is illustrated by a drawing illustrating one of the options for constructing a relay and communication system that implements the proposed method.

In Fig. 1, the following designations are introduced:

1, 2, 3 - satellites-repeaters on daily HEO;

4 - Earth;

5 - daily HEO;

6 - multi-beam transceiver antenna;

7 - GSO;

8, 9 - satellites-repeaters in the GSO;

10 - steerable transceiver antenna;

11 - multi-beam coverage area;

12 - area of a separate beam of a multi-beam antenna;

13 - multi-beam antenna beam;

14 - conical surface, limiting the area of formation of a multi-beam coating;

15 - subscriber earth stations;

16 - central earth stations;

17 - space users in near-earth orbits;

18 - near-earth orbit;

19 - space subscribers starting from the Earth's surface;

20 - antenna of the main inter-satellite communication;

21 - line of trunk inter-satellite communication;

22 - line of subscriber inter-satellite communication.

In accordance with Fig. 1, the space relay and communication system includes relay satellites 1, 2, and 3 (hereinafter referred to as highly elliptical SR), orbiting, as an example, around the Earth 4 by diurnal HEO 5 with spaced 120 ^{about the} longitudes of the ascending nodes equipped with large 6 L or S band multibeam transmit-receive antennas and associated repeaters. In addition to them, at least two repeater satellites 8 and 9 (hereinafter referred to as geostationary SRs) circulate around Earth 4 according to GSO 7, the angular separation between which is close to 180 ^° , equipped with retargetable transceiver antennas 10 of the radio frequency (from Ka and above) or optical range and associated repeaters. SR 1 is located over the territory of Russia, and antenna 6 forms on the surface of the Earth 4 a multi-beam coverage zone 11, in which zones 12 of rays 13 (for simplicity, only one ray is shown in Fig. 1) fill the entire specified zone 11. The formation area of zone 11 is limited a conical surface 14, the minimum angular size of which is determined by the dimensions of the zone 11, visible from CP 1 at the moment CP 1 is above the center of this zone. Depending on the purpose of the space relay and communication system, zone 11 can cover both the territory of Russia and the entire surface of the Earth 4 visible from the SR, limited by the working elevation angles of the served subscriber earth stations 15, hereinafter referred to as earth subscribers, and central earth stations 16. Location for convenience, these earth stations in zone 11 are shown in FIG. 1 in a separate enlarged plan.

Since CP 1 also carries out information exchange with space users 17 in its field of view, circulating in low-earth orbits 18, or space users 19 starting from the Earth's surface 4, the size of the conical surface 14, and hence the number of beams 13 of antenna 6 will be determined by the requirements for the spatial coverage of space users 17 and 19.

When located in the active section VEO 5, SR 1 provides information exchange of low-energy terrestrial 15 and space 17 and 19 subscribers with the central earth station 16 on the territory of Russia. Highly elliptical repeater satellites 2 and 3 similar to SR 1 are out of sight from the territory of Russia during the period under consideration, therefore, information received by highly elliptical SR 2 and 3 from the aforementioned terrestrial and space subscribers is relayed through antennas 20 along the inter-satellite communication trunk line 21 to the nearest geostationary SR (on 1 these are respectively geostationary CPs 8 and 9) for subsequent transmission to one of the central earth stations 16 (the communication lines of all CPs with the central earth stations are not shown).

Space users 17, orbiting in low near-earth orbits 18, according to their intended purpose, can be both low- and high-energy, requiring for information exchange with them, respectively, channels with low bandwidth of the order of units - tens of kilobits per second (L or S band) and with high throughput of the order of hundreds of megabits per second and higher (Ka or optical range). Low-energy space subscribers in the system under consideration are served by highly elliptical CPs 1 - 3 via multi-beam antennas 6, and high-energy ones - by geostationary CPs 8 and 9 via steerable single-beam antennas 10 via subscriber lines of inter-satellite communication 22. As shown in RF patent No. 2412547, C two geostation angles a spacing between them of about 180 ° is quite enough to service existing high-energy space users (mainly spacecraft for remote sensing of the Earth) at any point of their orbits with an altitude of 300 to 800 km (Shovengerdt R.A. Remote sensing. Models and methods of image processing. M. : Technosphere. 2010.560 s., P. 546).

In the process of mutual movement of highly elliptical SRs 1 - 3 and geostationary SRs 8, 9, the spatial position and length of inter-satellite communication trunk lines 21 will change. At certain points in time, lines 21 may be eclipsed by Earth 4 and the adjacent atmospheric layer, which will lead to disruption of their operation. The presence in the space system of relaying and communication of two geostationary SRs provides each of the highly elliptical SRs 1 - 3 with a fundamental opportunity to select a communication line 21 with geostationary SRs 8, 9 with a direction that guarantees the absence of its eclipse by the Earth 4 during a communication session with a specific space subscriber, and also with the direction providing the smallest length of the specified communication line.

This control can be carried out by onboard control systems of all relay satellites by means of measuring their current navigation parameters implemented in existing automated control systems for spacecraft (Chebotarev V.E., Kosenko V.E. Siberian State Aerospace University 2011.488 p., Pp. 166 - 171).

Imposing on geostationary SRs, in addition to providing relaying information from low-energy space subscribers from highly elliptical SRs, the task of relaying information from high-energy space subscribers allows concentrating information exchange functions with all types of space subscribers within one space relay and communication system, which is typical for all "classical »DAC.

Thus, the use of the proposed method provides a reduction in the coverage sectors of antennas for the main inter-satellite communication between highly elliptical and geostationary relay satellites, the continuous operation of the main inter-satellite communication lines and a decrease in energy costs when transmitting information along these lines.

According to the results of the analysis of the known patent and scientific and technical literature, carried out by the author, a set of features equivalent (or coinciding) with the features of this alleged invention was not found, therefore the applicant is inclined to consider the technical solution to meet the "novelty" criterion.

Claims (1)

A method for constructing a space relay and communication system, in which information exchange between low-energy earth and space subscribers and central earth stations is carried out through relay satellites in high elliptical orbits containing multi-beam antennas, characterized in that the composition of the orbital constellation of the said space relay and communication system is , at least two satellites-repeater in geostationary orbit, the angular separation between which is set close to 180 °, each satellite-repeater in geostationary orbit is equipped with steerable antennas of the radio frequency or optical range, with the help of which they carry out information exchange with high-energy space subscribers, satellites - repeaters in highly elliptical and geostationary orbits are equipped with steerable antennas for communication between repeater satellites in highly elliptical and geostationary orbits, with the help of which they carry out information exchange between low-energy space and terrestrial subscribers and central earth stations during the period when relay satellites are in a highly elliptical orbit outside the visibility zone of central earth stations, on all relay satellites they carry out current control of the spatial position of communication lines between relay satellites in highly elliptical and geostationary orbits , select the specified communication line with the smallest length and exclude information exchange over it during its eclipse by the Earth or the adjacent atmospheric layer.

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