RU2619582C2 - Multifunctional satellite communication system - Google Patents

Abstract

FIELD: physics, communications.

SUBSTANCE: invention relates to communication engineering and can be used to provide mobile and fixed satellite communication services. The system consists of an orbit group as part of four spacecraft on a highly elliptical orbit and two spacecraft on a geostationary orbit, a flight control centre, a mobile communication control centre, a fixed communication control centre, ground base stations for setting up communication and providing interfacing with external networks and ground means for mobile and fixed communication consumers.

EFFECT: invention improves flexibility of using the system, while allowing subscribers to choose the required subscriber terminal based on their needs in communication services and financial abilities.

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Description

The invention relates to global satellite information systems.

This invention can be used to provide satellite communication services and high-speed Internet access in the Russian Federation and neighboring countries.

At present, the Russian Federation does not have its own satellite system that provides uninterrupted service to the entire territory of the country and provides personal voice communications and high-speed broadband Internet access. Foreign systems operating on the territory of Russia are distinguished by the high cost of their services, do not provide the entire list of services needed by Russian consumers, and a significant part of the territory of the Russian Federation, especially hard-to-reach and northern regions, are outside the coverage of foreign systems. All this limits the possibilities of their application and makes it necessary to create a domestic system of personal satellite communications and providing high-speed Internet access.

The main direction of improving the system is the effective use of the frequency-orbital resource, the optimization of the structure of the orbital group to provide services to the territory of the Russian Federation and the CIS countries in order to optimize the costs of creating a system to increase its economic efficiency.

Currently, various systems of multifunctional space communication systems are known in which it is proposed to use satellites in geostationary (GSO) and highly elliptical (HEO) orbits (patents RU No. 366086, 2223205, 2360848).

There is a method of constructing a space relay system using geosynchronous relay satellites (Patent RU 366086 C1), the technical result of which is to maximize the time of using satellite relay in orbit. The system is constructed using satellite transponders in high elliptical orbits of the Tundra type and having longitude nodes separated by 120 °. Subscribers of the system are earth stations and low-orbit spacecraft operating in the general wavelength range. Repeater satellites are equipped with multi-beam antennas, the central group of beams of which serves ground subscribers while the spacecraft is in the service area, and the peripheral one - for space subscribers. When the spacecraft is outside the service area of terrestrial subscribers, all the beams of the multipath antenna are used to service space subscribers.

The disadvantage of this system is the use of a high elliptical orbit of the “Tundra” type with a high apogee height at the working area of 43,000 km, which significantly reduces the energy of radio links. The use of spacecraft only in high elliptical orbit requires the complication of subscriber equipment due to the need for a “handover” procedure. In addition, the system does not provide for the possibility of servicing private consumers with small-sized subscriber terminals.

Also known is a satellite communication system in elliptical orbits, emulating the characteristics of a satellite system in a geostationary orbit (Patent RU 2223205 C2), the technical result of which is to increase the stability of virtual positions of satellites in service areas and reduce the limits of redirection of terrestrial antennas from one satellite to another when using space devices in highly elliptical orbits. The result is achieved by placing communication satellites in elliptical synchronous (~ 12 hour) orbits having the same inclinations, eccentricities, perigee arguments, Greenwich longitudes of the ascending node and the intervals between the passage of successive satellites of this Greenwich longitude. Each orbit is characterized by the presence of two points of intersection of its path at the apogee section (loop in the form of "8"). Ground communication stations are designed to operate via satellite within the ascending and descending sections of its orbit from the second (closest to the apogee) intersection point to the apogee. The emulated pseudo-stationary orbit (the set of virtual satellite positions in the apogee region) is located at altitudes of 32,000 ÷ 40,000 km, in the latitudinal belt 59 ÷ 64 ° N (or s). Smooth drift of satellites occurs within 5 °. The orbital constellation has, in particular, 4 satellites emulating two stationary positions shifted 180 ° in longitude.

The disadvantage of this system is the use of satellites only in high elliptical orbits, despite the emulation of the geostationary orbit, a “handover” procedure is necessary to ensure uninterrupted communication with subscribers.

Closest to the proposed system is a multipurpose space system (Patent RU 2360848 C1) for servicing a vast geographical region based on high-orbit and low-orbit spacecraft (SC) and ground-based communications and control points, including at least four spacecraft in highly elliptical orbits, including two spacecraft for meteorological and geophysical monitoring, at least two specialized communication spacecraft, as well as one or two spacecraft in low orbits for radar monitoring.

The disadvantage of this system is the large number of spacecraft in different orbits in the orbital constellation, which increases the cost of the system and complicates its commissioning and further maintenance, and also creates difficulties in relaying information from low-orbit spacecraft. In addition, the application proposes to use the minimum number of spacecraft (2) in high elliptical orbit for satellite communications, but this will not be enough for uninterrupted customer service.

The objective of the present invention is to eliminate the disadvantages of analogues and prototype, creating a satellite communications system to provide mobile satellite communications to consumers throughout Russia, including the Arctic zone of the Russian Federation, as well as providing satellite channels for broadband fixed satellite communications.

The problem is solved in that the multifunctional satellite communications system includes the orbital constellation of spacecraft in geostationary and highly elliptical orbits, it also includes a flight control center, a mobile communications control center, a fixed communications control center, base earth stations for organizing communications and providing interfacing with external networks and terrestrial means of consumers of mobile and fixed communications.

The invention is illustrated in the figure, which illustrates a particular case of building a system.

In FIG. Figure 1 shows the guaranteed zones of radio visibility by the elevation angle of 10 ° of the spacecraft orbital grouping on the HEO and GSO.

The system should consist of an orbital constellation of four spacecraft in a highly elliptical orbit of the Molniya type and two spacecraft in a geostationary orbit, a flight control center, a mobile communications control center, a fixed communications control center, base earth stations for organizing communications and interfacing with external networks (landline telephone networks, mobile operators, the Internet) and terrestrial consumers (subscriber terminals) mobile and fixed communications.

In this case, the service area of the orbital constellation from SC to VEO should include the territory of the Russian Federation, including the Arctic zone of the Russian Federation and the Arctic Ocean basin, and the service zone from SC to GSO should include the territory of the Russian Federation up to 70 degrees north latitude and the territory of the CIS countries.

On board spacecraft, it is proposed to place two airborne relay complexes of broadband fixed satellite communications and mobile satellite communications. In the radio links of a personal mobile satellite communication system, L- and S-frequency bands for subscriber lines, C- and Ku-frequency bands for feeder lines can be used. The proposed system will be able to provide services to up to 300,000 mobile satellite subscribers. For broadband fixed satellite communications, it is proposed to use the Ku- and Ka-frequency bands.

The on-board mobile repeater should include a feeder-line transceiver antenna, a subscriber communication line transceiver antenna, including a digital beam-forming circuit, this will provide high energy in subscriber lines, thereby simplifying and reducing the size of subscriber terminals. In addition, this will make it possible to quickly reconfigure the antenna beams, which will allow you to redistribute the energy between different antenna beams depending on the needs of subscribers.

For the organization of mobile communications, digital signal processing on board spacecraft must be provided; for this, a special signal processing unit must be included in the mobile communications repeater. This unit is designed for receiving at an intermediate frequency signals from the receiving paths of the onboard repeater, their analog-to-digital conversion, digital beamforming, frequency selection of signals and their switching, as well as for generating group radio signals for transmission to the transmitting paths of the onboard repeater.

A distinctive feature of the proposed system is the possibility of using three different types of subscriber terminals for organizing mobile communications: terminals in the form of a handset with an omnidirectional antenna, portable laptop-type terminals with an antenna aimed at the spacecraft, and subscriber terminals intended for installation on vehicles.

A multifunctional satellite communication system works as follows: when organizing communication between two subscriber terminals in the system, a connection request comes from one terminal through a relay on board the spacecraft to the base earth station and the communication control center, which transmits a call request through the base station and the on-board relay to another terminal. After the connection is established, the communication channel is organized directly through the onboard repeater by switching the signal through the signal processing unit on board the spacecraft. When establishing a connection with a telephone subscriber of terrestrial telephone networks, cellular networks and the Internet, a connection request is received from the subscriber terminal through the spacecraft repeater to the communication control center, which issues a command to connect and the system subscriber is switched through the base earth station to external communication networks.

Achievable technical result of the use of the combined orbital constellation of spacecraft at GSO and VEO is the provision of satellite mobile communications and broadband fixed communications in the Russian Federation, including the Arctic zone of the Russian Federation and the Arctic Ocean basin, as well as the CIS countries. The use of digital signal processing, as well as multi-beam antennas with digital beamforming in a mobile satellite communications repeater, will improve energy in subscriber communication lines, which will reduce the size and cost of subscriber terminals. The ability to use subscriber terminals of various cost, dimensions and energy characteristics increases the flexibility of using the system, allowing subscribers to select the necessary subscriber terminal based on their communication needs and financial capabilities.

Claims (3)

1. A multifunctional satellite communications system, including the orbital constellation of spacecraft (SC) in geostationary (GSO) and highly elliptical (VEO) orbits, characterized in that it includes a flight control center, a mobile communications control center, a fixed communications control center, basic earth stations for organizing communications and interfacing with external networks; and terrestrial means of consumers of mobile and fixed communications, and a digital signal processing unit. 2. The multifunctional satellite communication system according to claim 1, characterized in that three different types of subscriber terminals are used as terrestrial means of consumers. 3. The multifunctional satellite communication system according to claim 1, characterized in that the spacecraft are equipped with repeaters of fixed and mobile communications.

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