At the present time, the earth facilities of the first and second generations are used to provide the CS. The means of the first generation form the satellite communication complex "Crystal", the second - "Rain" and "Legend". In the Kristall complex, the basic (basic) stations are the P-440-U hubs and the P-440-O end stations, and in the Downpour complex, the R-441-U hubs and the P-441-O terminal stations.
Station of space communication P-440-O in stationary execution
Spacecraft with transponders on board provide simultaneous operation of a large number of ES with each other. The main role is played by a repeater with a set of receiving and transmitting antennas. The simplest transponder is a transceiver, through which weak ES signals captured by the receiving antenna are separated from the noise in the receiver, transferred in frequency to avoid repeater excitation, amplified in the transmitting device and transmitted via the transmitting antenna in the direction of the Earth. The rest of the equipment of the spacecraft is the power supply and life support systems of the repeater. In practice, more complex repeaters are also used in which the ZS signals are demodulated and combined into a common group signal transmitted to Earth.
Satellite communication station P-441-UVS
The system of CS includes several spacecraft in geostationary orbit (GSO) of the type "Edge" and "Globus-1". Spacecraft of the type "Gran" provide the spacecraft of the Kristall complex, and spacecraft of the Globus-1 type - the spacecraft of the Rain and Legend complexes. Each spacecraft serves a specific part of the earth's surface (zone). The service area of a spacecraft is determined by the position of the spacecraft relative to the Earth and the antenna used. The points at which the data of the spacecraft are displayed are determined by international agreements.
Spacecraft at the GSO do not support the operation of ES from high-latitude regions, therefore, to solve this problem, the spacecraft system includes the spacecraft of the "Lightning-3" type in high-elliptical orbits (VEO), from which these areas are well visible. Spacecraft on VEO make one revolution around the Earth in 12 hours, and using it for communication is possible only during 6 hours. Therefore, to ensure round-the-clock work, 4 devices of this type are needed, which form the so-called "four". The system may include several "fours", which allows for the operation of a large number of stations. Spacecraft of the "Molniya-3" type are designed for the operation of earth stations of the "Crystal" complex.
Communication repeaters are designed to relay satellite satellite communication signals. They are installed on spacecraft displayed on the geostationary and HEO. In a satellite communication system, repeaters with direct retransmission (OL) and on-board signal processing (RSD) are used.
In the first case, the repeater provides reception of signals from the ES, their selection, frequency conversion, amplification and transmission. The signals at the input and output of the repeater differ in frequency shift.
The advantage of this type of repeaters is the simplicity and the possibility of using for the operation of earth stations of any type, the working frequency range of which coincides with the frequency range of the repeater.
The disadvantages of these repeaters are due to the need for simultaneous frequency conversion and amplification of a large number of signals (by the number of stations operating in the trunk). With direct retransmission, the power of the output power amplifier is distributed between all signals received at its input, including interfering ones (such as the receiver's own noise, intentional and unintentional interference), so part of the power is lost. In addition, when several signals are simultaneously amplified, so-called combinational noise arises, which also consumes part of the power. In addition, these interference may coincide in frequency with the useful signals, degrading the quality of their reception. Finally, during direct retransmission, noise accumulates: the earth station receiver, along with the useful signal, receives the noise formed by the receiver of the repeater, which, adding to the earth station receiver’s own noise, degrades the quality of the radio link. For normal operation of satellite communication lines using direct retransmission, it is necessary to reduce the number of stations simultaneously operating in one trunk. Trunks with signal processing, usually as an emergency or backup, have a direct relay mode.
When using direct retransmission to work with several correspondents, each earth station should have the number of receivers by the number of correspondents and each of the receivers should be tuned to its own frequency. This leads to the complication of earth stations and creates certain difficulties if it is necessary to increase the number of directions and communication channels formed by them.
Repeaters with RSD are different in that the signals received from the ES are demodulated and, as a rule, are combined into a trunk group (HS) signal. At the same time, disadvantages inherent in direct retransmission are largely eliminated.
Repeaters of this type are much more complex than repeaters with PR and can only work with a specific fleet of earth stations. Their use allows to significantly increase the bandwidth due to more productive use of the output power amplifier of the trunk.
As a rule, several sets of receiving and transmitting equipment are installed in one repeater. Each such set of equipment forms a transponder trunk, and in the first case, the trunk provides direct signal relaying and is called a forward relay trunk, and in the second case, the trunk provides full signal processing (demodulation) and is called a signal processing trunk. Usually consider separately receiving and transmitting tracts of the trunks, calling them respectively receiving and transmitting trunks.
Each barrel has its own operational and technical mission, associated with the need to retransmit signals of a certain group of earth stations. For example, for the operation of a central station with several terminals, two trunks with direct relay can be allocated: one for the operation of the central station, the second for a group of terminal stations.
Each transponder trunk operates in its own frequency band of a certain range. Currently, the system uses the 4 / 6; 7 / 8 and 0,2 / 0,4 GHz bands (the first digit refers to the section ZS-RS, the second to the section RS-ZS). The frequency band allocated to one trunk ranges from hundreds of kilohertz to hundreds of megahertz, depending on the purpose of the trunk.
Signals received in one trunk may be transmitted in another. This allows you to organize oncoming work stations for different purposes when using different trunks. This possibility is realized in the presence of interswitch (cross) links. Inter-trunk communications are most easily realized in trunks with on-board signal processing, since in this case low-frequency signals are switched.
Earth stations operating through a common trunk form a specific grouping, as a rule, geographically quite compact. Therefore, each trunk usually works with its own antennas — receiving and transmitting (sometimes receiving and transmitting antennas are used) with high directivity, which allows them to “illuminate” (serve) certain areas on the earth's surface, called service areas. Thus, each trunk corresponds to a specific service area. If it is necessary to change the service areas, in some cases the antennas can be reoriented by commands from the Earth. The use of highly directional antennas that form predetermined service areas makes it possible to reduce mutual interference between communication devices and the likelihood of radio suppression from the enemy.
If the antenna "illuminates" the entire surface of the Earth visible from a spacecraft, then the generated service area is called global. In this case, the antenna is said to provide global service. Global service is very convenient for building an alert system. If the antenna "illuminates" only part of the surface of the Earth, then the service is zonal. Zone service allows you to protect the radio link from intentional interference and improve its operation by concentrating the radiated power of the useful signal in the direction of the correspondent. Zone maintenance is convenient for the operation of one central earth station or a group of closely located stations (located in one zone).
For the operation of earth stations of the Kristall complex, the Delta repeaters (Grani satellite in geostationary orbit) and Segment (Molniya-3 spacecraft in high-elliptical orbit) are used, and for the Earth stations of Liven and Legend complexes "- repeater" Citadel "(satellite" Globus-1 "in geostationary orbit).
Mobile earth stations of satellite communication Р-440-0, Р-441-0, Р-439
Satellite communications stations P-440-0, P-441-0 and P-439 are designed to provide long-distance multi-channel radio communications and alerts using repeaters on artificial Earth satellites.
The stations are operated using repeaters installed on spacecraft placed on geostationary and elliptical orbits. The stations provide duplex telegraph, telephone, facsimile, telecode communication and data exchange via digital (discrete) channels. The channels formed by the stations have unified input / output parameters (joints), which allows you to connect to them the terminal equipment of various types.
The stations provide interference-free (PMZ) mode of operation, which provides the ability to conduct communication in the presence of interference, including intentional.
Satellite communication station P-440-0
The satellite communications station is a single-satellite satellite communications complex of the Kristall complex, operating through repeaters installed on spacecraft of the Grani and Molniya-3 types, which are put into geostationary and highly elliptical orbits, respectively.
Counter work with the stations of the Kristall complex is provided. The frequency range used is 4 / 6 GHz. The station provides reception of special signals on a separate carrier and in the general group signal.
The composition of the station's equipment allows 1-2 to arrange satellite communication directions with a maximum group signal rate per 4,8 or 5,2 kbit / s transmission. At the same time, medium-speed digital information channels are formed with the transmission speed 1,2; 2,4 or 4,8 kbps, as well as low-speed telegraph channels with transmission speeds up to 100 baud, distributed between two directions of communication according to needs. The number of formed channels of various types is determined by the capabilities of the Discrete equipment used in the station. So, at 4,8 kbps transmission speed, 3 channels can be organized over 1,2 kbps and 2 channels over 100 bits / s distributed between two directions of communication. Other channeling options are possible. When the speed of the group signal 5,2 kbps, it is possible to work in one direction of communication over the channel at a speed of 4,8 kbps. The channeling capabilities of the station are discussed in more detail below.
In addition to the listed information communication channels, low-speed telegraph channels of formalized service communication with 50 baud speed are organized in each communication direction.
If necessary, the station can be used in a noise-free mode using special jamming equipment. In this case, it is possible to organize one single-channel direction of communication with the information transmission rate 100 or 1200 baud. The service channel is saved.
The main technical and operational characteristics of the station are given in the table.
Station Р-440-0 is mounted on one car URAL-375. The body is divided into two compartments.
During transportation, the AK-12 antenna device and two autonomous power sources AB-8-T / 230 are placed during transportation. The aerial device for operation is lifted with the help of a lifting device from the front compartment and is fixed on the roof of the control room.
Satellite communications station P-441-O
The satellite communications station Р-441-О is a mobile station of the “Rain” complex, mounted on two transport units: the URAL-4320 vehicle and the trailer. The station operates through repeaters installed on spacecraft of the Globus-1 type (in geostationary orbit) and Meridian (in high-elliptical orbit).
Reciprocal work is provided with the stations of the "Rain" and "Legend" complexes. The 4 / 6 and 7 / 8 GHz bands are used for operation (the 1 and 2 range, respectively). The composition of the equipment allows simultaneous reception of signals in both specified ranges, and transmission - in one (optional).
It is possible to transmit and receive special signals on a separate carrier and in a common multicast signal.
The station allows you to organize 1 ... 8 directions of satellite communications at the speed of the group signal to transmit up to 12 kbit / s. At the same time, medium-speed channels with 1,2 transmission speed can be formed; 2,4; 4,8 and 9,6 kbps, as well as low-speed channels with transmission speeds up to 100 bits / s.
The capacity of the station in terms of channeling is determined by the Agat equipment used in it for temporary unification / separation. The number of channels and directions of communication formed is related to the speed of the group signal for transmission as follows. The group signal is formed from 1,5 kbit / s base sequences, each of which combines one 1,2 kbit / s signal and one 100 bit / s signal, as well as service sequences. Thus, when the 12 HS speed is in kbps, 8 channels are generated over 1,2 kbps and the same number of 100 bits / s channels that can be distributed between the directions of communication. If it is necessary to organize higher-speed channels, the basic sequences are combined and the number of possible directions of communication is reduced.
In each direction of communication, a telegraph channel of formalized service communication is organized, distinguished from the total number of telegraph communication channels formed by the station.
The station provides work in a noise-proof mode. The main option is to work on the transmission of signals with a pseudo-random tuning of the operating frequency (frequency hopping), and at the reception - FM-ShPS (when working in the 4 and 5 trunks of the Citadel repeater). In trunks with direct relaying of signals can be applied to the transmission and reception of the mode with FM-ShPS.
The equipment of the station provides operation in the radio-PBX mode both on fixed and non-fixed repeater lines. The station has an automated control implemented using the automated control subsystem (PAH). PAH provides the implementation of all functions of station management.
The main technical and operational characteristics of the station are presented in the table.
The station is located on two transport units: the car URAL-4320 (hardware У023) and trailer (hardware У022).
The body of the U023 hardware is divided into two compartments. The U100B-U antenna device (in transport position), the MAD-127 / 220 dehydrator and power supply elements are placed in the front compartment, and the AD-30-T / 400-1В electrical equipment is in the rear compartment. On the antenna device, the input devices 1 and 2 of the range (KN-302TE and KU-302ЛТ respectively) are installed. To operate the antenna device on the machine rises from the compartment and is mounted on the roof of the hardware. Station equipment is placed in the trailer. In operation, the hardware is interconnected by cables from the station kit, and a high-power elliptical waveguide serves to transmit a high-power microwave signal to the antenna.
Satellite station P-439
The satellite communications station P-439 is a mobile station of the Legend complex.
The station operates through repeaters installed on spacecraft of the Globus-1 type (in geostationary orbit) and Meridian (in high-elliptical orbit). Reciprocal work is provided with the stations of the "Rain" and "Legend" complexes. The operating frequency range is 4 / 6 GHz. It is possible to receive special signals on a separate carrier and in the general group signal.
The station allows you to organize 1 ... 4 satellite communication directions at the speed of the group signal to transmit up to 6 kbit / s. At the same time, medium-speed channels with 1,2 transmission speed can be formed; 2,4; 4,8 kbps, as well as low-speed channels with transmission speeds up to 100 bits / s. The capacity of the station in terms of channeling is determined by the Agat equipment used in it for temporary unification / separation. The number of channels and directions of communication formed is related to the speed of the group signal for transmission as follows.
The group signal is formed from 1,5 kbit / s base sequences, each of which combines one 1,2 kbit / s signal and one 100 bit / s signal, as well as service sequences. Thus, at a 6 HS rate, kbps 4 channels are generated over 1,2 kbps and the same number of 100 bits / s channels that can be distributed between the directions of communication. If it is necessary to organize higher-speed channels, the basic sequences are combined and the number of possible directions of communication is reduced.
In each direction of communication, it is possible to organize a telegraph channel of formalized service communication, separated from the total number of telegraph communication channels formed by the station.
The station provides work in a noise-proof mode. The main option is to work on the transmission in the frequency hopping mode, and to receive - FM-ShPS (when working in the 4-m trunk of the Citadel repeater). In trunks with direct relaying of signals can be applied to the transmission and reception of the mode with FM-ShPS.
The main variant of the station operation is operation in the radio PBX mode both in fixed and non-fixed communication directions (repeater lines), implemented in the 4 trunk of the Citadel repeater. When operating in the radio-PBX mode in fixed directions, the station constantly works on radiation at a speed of 6 kbit / s, occupying one of the repeater lines allocated to it. At the same time, 4 channels are formed over 1,2 kbit / s, which are provided to subscribers on demand at the time of negotiations. When working in non-fixed directions (rulers), the station is switched on to radiation as needed for the duration of the negotiations, providing the subscriber with one channel with a speed of 1,2 kbit / s, while the transmission rate is 1,5 kbit / s.
When the station is operating in the 1 trunk, it is possible to organize a radio PBX mode in a fixed direction on 2 channels with 1,2 kbit / s speed from the 4-x channels formed by the station at 6 kbit / s group signal speed. All 4 channels can be used as pinned.
The station includes a set of terminal single-channel equipment, which allows the use of the formed communication channels directly from the equipment room.
The control of the station is automated, implemented with the help of a control computer of the station.
The main technical and operational characteristics of the station are presented in the table.
The station is located on two transport units: the car URAL-4320 and two-axle trailer. Body hardware is divided into two compartments. The front compartment houses the AK-12ShDL antenna device (in transport position) and the CTC-10 / 0,5C stabilizer. The H302TE input device is installed on the antenna device. To operate the antenna device on the machine rises from the compartment and is mounted on the roof of the hardware. The trailer has a power station ED2х8-Т / 400-1ВПС ("Toluene"). In the rear compartment (operator compartment) station equipment is located. Outside the hardware installed heater ОВ-65 and filter unit FVUA.
Low-energy satellite communications stations.
Satellite communication station Р-439П
The earthly transportable satellite communications station P-439P is designed to organize satellite communications lines and networks using communication repeaters on the Globus-1 and Yamal satellites in geostationary orbit.
Directions and satellite communications networks at P-439P stations can be deployed in the interests of solving control problems at the tactical, operational-tactical and higher levels of command and control or for solving special tasks. In these networks (directions) on a digital duplex communication channel with speed 1,2; 2,4; 4,8 or 9,6 kbit / s provides for the transmission of the following types of messages:
- encrypted telephone or data transmission;
- open telephone connection when pairing with PBX;
- transfer of machine-to-machine data exchange;
- transmission and reception of a call, and maintenance of an open telephone connection directly between the station operators using built-in vocoder voice processing devices (RPU).
In this case, the station produces a single-channel duplex direction of communication with the frequency (frequency-code) method of multiple access in the trunks with PR signals.
The satellite communications station P-439P provides simultaneous reception and transmission without manual search and adjustment at any frequency that is a multiple of 500 kHz with a step of 500 kHz in the frequency bands:
3533 ± 8MHz - in the barrel number 2 satellite Globus-1;
3477,5 ± 5 MHz - in the barrel number 3 satellite Globus-1;
3473,75 ± 2,25 MHz - in the barrel number 2 AES "YAMAL";
5858 ± 5 MHz - in the barrel number 2 satellite Globus-1;
5765 ± 5 MHz - in the barrel number 3 satellite Globus-1;
5799,75 ± 2,25 MHz - in the barrel number 2 IZZ "YAMAL"
The station provides transmission and reception of information signals over a duplex digital channel in the modes of operation at the speeds indicated in the table.
Satellite station Р-438Т
The small-sized (portable) satellite communications station P-438 ("Barrier-T (TC)") is designed to provide satellite communications in the interests of front-line and army intelligence, as well as airborne and airborne assault connections. There are other options for its use, including for the provision of individual links in RAM and RAM.
The main features of the station are:
- small dimensions (the station is made in the form of a rectangular package with built-in waveguide-slot antennas, the package dimensions are 500x480x180 mm);
- low weight (the weight of the station equipment kit is about 15 kg.);
- low power consumption (no more than 90 W);
- the ability to work in duplex and simplex information exchange networks;
- the absence of anti-interference methods of information transmission;
- low bandwidth (channel transfer rate not more than 1200 baud);
- availability of the station automation control system and control over the functioning of its elements.
Satellite communications networks using P-438 stations are operated in trunks with PR signals (trunk No. 4) of the RS on the Globus-1 (Globus) satellite in stationary orbit. In this case, the frequency method of MD stations to the trunk of the signal relay, divided into 10 operating frequencies over 50 kHz, is 500 kHz (5859, 75 ... 5860, 25 MHz). The frequency range of the trunk transmission has the same band and number of operating frequencies at their nominal 3634,75 ... 3635,25 MHz.
Depending on the applied OA in the networks (directions) of communication of portable stations the following types of communication can be provided:
- telephone secret guaranteed durability using equipment such as T-230-1А ("Flywheel"), "Stability";
- classified data transmission using T-235-1U (B) equipment;
- secret PD using the correspondent sensor “Olkhon-PC”;
- non-secret service PD from TLU from the station with the possibility of conducting formalized service communication, transfer (reception) of the “Receipt” commands, information exchange between stations using the TLU buffer memory, automatic reading of the formalized service information or information from the TLU correspondent memory.
The terminal equipment mates with the P-438 station only at the C1-FL-BN (C1I) interface at the speed of information transmission in the 1200 Bod channel. In the trunk number 4, and RS "Citadel" can be organized several networks and directions of communication of portable stations.
Upgraded satellite communications station Р-438М
By the nature of information exchange, satellite communications at P-438 stations can be simplex or duplex. In the case of simplex satellite communications, work between stations is carried out using the same transmission and reception wave number. With full-duplex satellite communications, the transmitting and receiving stations operating between each other simultaneously lead to different numbers of transmitting and receiving waves.
Station P-438 provides work:
in simplex mode:
- with data transmission equipment (APD) of type T-235-1U;
- with a correspondent sensor (CD) "Olkhon-PK";
- with equipment of type T-231-1U (“Stability”);
- from the TLU station with a preliminary set of information on the keyboard;
in duplex mode:
- telephone communication - with equipment of type T-230-1А, “Stability”;
- telephone connection - with the AT-3006 equipment (directly or through T-230-1А);
- with data transmission equipment of type T-235-1U.
The central station Р-438Ц ensures the work in the same modes, as well as the simplex communication in the DB mode using the P-115А equipment.
In all operating modes of the P-438 stations, simultaneous reception of codograms is provided via the second reception channel (control channel) with recording of information into the memory device and its display on the remote (central) control panel.
In the absence of work on the main (operational) channel, it can be used for service communication between station operators by transmitting formalized commands from the remote (central) control panel.
Main technical characteristics of P-438T
Operating frequency range:
- transmissions - 5860 MHz;
- reception - 3635 MHz.
The number of operating frequencies - 10.
Working frequency grid - 50 kHz.
The transition time to another frequency - no more than 10 with.
Transmitter power - at least 25 watts.
- transfer - at least 22 dB;
- At the reception - at least 19 dB.
The polarization of the radio signal is circular.
The probability of error in the channel Rum ≤ 10-3 when the ratio of the signal energy to the spectral density of the noise power E / N0 ≥ 9 dB.
Reception method - quasi-coherent reception of signals from OFT.
Synchronization time of the demodulator in the mode of receiving codograms with E / N0 ≥ 9dB with probability 0,9 - does not exceed 2 s.
The type of signal manipulation is relative phase.
The method of pointing antennas to a repeater is manual, using nomograms.
The power supply is an alternating current network with voltage 220 / 127 V, a constant current source is 12 (27) B.
Power consumption from the power supply - no more than 90 watts.
The weight of the station kit is no more than 15 kg.
Packing dimensions 500х480х180 mm.
The number of operators is one.
Station deployment time - no more than 3 min.
Mean time to failure - at least 1000ch.
The average recovery time of a station under military conditions is no more than 30 min.
Formal service communication between station operators is carried out using TLU and CU. They provide the transmission and reception of 512 binary decimal places. The characters are read and typed on the LED display of the TLU display in groups of 5 characters in each group.
Satellite communications at P-438 stations can be simplex or duplex. In case of simplex communication, the stations operating between themselves transmit and receive alternately on the same frequency (wave). In full-duplex communication, the stations operating between each other transmit and receive simultaneously at different frequencies (waves) of transmission and reception.
The transmission (reception) of information at the P-438 station can be provided:
- with preliminary accumulation of information in the memory of the TLU - when working as a correspondent sensor (CD) “Olkhon-PK” or when entering a codogram from the TLU keyboard. Up to two codograms of the maximum length of the CD format can be recorded in the memory of the TLU - one per transmission, one per reception. Each codogram contains 510 binary decimal places (102 five-digit group);
- with live transmission of information to the channel - when T-230-1А or T-235-1В are operating.
Ways to organize satellite communications
Satellite communication at the P-438 stations, depending on the tasks to be performed and the available bandwidth resource, can be arranged in the direction or in the network. In one trunk of the RS, several networks (directions) of satellite communications of portable stations can be organized.
Satellite communication direction - a method of organizing satellite communications between two stations. The direction of satellite communication can be simplex or duplex, in which secured telephone (T-230-1А) communication, data transmission (T-235-1В, "Olkhon-PC") or non-secret data transmission from the TLU station can be provided.
Satellite network - a method of organizing satellite communications between three or more stations. A satellite communications network at P-438 stations can be organized:
- on one frequency (wave) of transmission and reception to ensure transmission of circular messages (formalized commands) from the main station of the network to network correspondents or to conduct alternate exchange of information (formalized commands) of the main station with stations of correspondents or between any correspondents of the network. At the same time, the TLU stations, the T-235-1В equipment or the Olkhon-PK sensor are used as the terminal equipment;
- when using two waves (transmission and reception, respectively) for alternate exchange of information from the main station of the network with the stations of correspondents;
- using three waves (transmitting, receiving the first and receiving the second for the service channel) to alternately exchange information from the main station of the network with the stations of correspondents and simultaneously receive formalized messages on the TLU through the service channel.
Service communication between station operators is carried out with the help of commands recruited on the TUU keyboard using the P-438 station operator negotiation table and transmitted in the absence of transmission of operational information. Reception of overhead communication commands can be carried out via the second reception channel of the station simultaneously with the reception of operational information via the first reception channel.
It should be noted that the barrel number 4, and for communication of portable stations of the satellite "Globus-1" has a limited bandwidth. To prevent overload of the repeater amplifier, stations can operate simultaneously on only eight out of ten operating frequencies.