Express
The creation of communication satellites in the USSR began in the 1960s at OKB-10 (later the Design Bureau of Applied Mechanics, now JSC ISS) under the leadership of General Designer M.F. Reshetnev. In the 1960s, the Strela-1 low-orbit communications satellites began their work, followed by the Molniya, Raduga, Ekran, and Horizon satellites. In 1994, the first satellite of the Express series was launched.
As of the end of 2019, 11 satellites of this series were operating in orbit. The largest and most powerful of them was Express-AM5, launched from the Baikonur Cosmodrome on December 26, 2013 by a Proton-M launch vehicle with a Breeze-M upper stage. Since the mass of the satellite exceeded the technical capabilities of the rocket to deliver cargo to high orbits, for the first time in the domestic satellite industry, a scheme was used to bring the satellite into a working orbit with a transfer orbit using its own electric propulsion engines.
Express
Nine months after Gals 1 was launched, Express 1 was inserted into a nearly GEO orbit. The Express series spacecraft closely resembling the Gals spacecraft which share a similar spacecraft bus. Express would replace the widely used Gorizont spacecraft, and current plans call for deployments at 13 locations (40 degrees, 53 degrees, 80 degrees, 90 degrees, 96.5 degrees, 99 degrees, 103 degrees, 140 degrees, 145 degrees, 205 degrees, 322.5 degrees, 346 degrees, and 349 degrees, all East longitude) just for domestic needs and to support the Intersputnik Telecommunications Association. Additional Express spacecraft may be sold to foreign companies, e.g., Rimsat, Ltd. While the Express solar arrays are identical to those on Gals, the spacecraft bus has slightly smaller dimensions of 3.6 m by 6.1 m. A typical Express payload would include 10 C-band and two Ku-band transponders. Express 1 reached its checkout location of 70 degrees E at the end of October and was scheduled to be moved to 14 degrees W shortly after the start of 1995
Russia’s Federal Space agency expects to launch three Express-AM Communications Satellites during 2007. The Express-AM33 was scheduled for launch during September 2007 while the Express-AM44 as well as the Express-MD1 was scheduled for December 2007. The Federal Space Agency further expects to launch two more communications satellites Express-AM4 and Express-MD2 during 2008. (References 262, 323, 325-328, 329).
Express-AM
The Express-AM artificial Earth satellite was designed for digital television and radio broadcasting, telephony, broadband Internet access, creation of departmental and corporate networks, and provision of multimedia services."Express-AM" was developed at the Research and Production Association of Applied Mechanics named after academician Mikhail Fedorovich Reshetnev together with French, Japanese and German partners.
This was a telecommunications geostationary satellite of a new generation. The broadcast of television and radio programs covers the territory of Russia, the CIS countries, Western Europe, the Middle East, India and North Africa. The starting mass of the satellite was 2600 kg. Estimated service life - 12 years. The spacecraft was equipped with modern antenna systems.
When in 1999 the program for the creation and launch of the Express-A satellites was approaching its final stage, the specialists of the RSCC made a forecast: By 2003, the need for capacities for VSAT networks would be higher than the need for capacities for television transmission , and by 2002 there was a shortage of capacity. A program for the further development of the Russian group was required. At first, the Troika program was adopted. According to the project, NPO Applied Mechanics and the alliance of OAO Gazkom and RSC Energia were identified as suppliers of satellites. The operator and suppliers had to find the financial resources for the implementation of the project on their own. Funding was the main problem.
In 2000, the Troika project was recognized as unrealistic, the plans were adjusted, but not fundamentally: for 2001-2002. It was planned to launch two Express-AYA satellites based on the Yamal-100 platform and two Express-AM satellites based on the Sesat platform. In 2003, it was planned to launch two more Express-AYA spacecraft and one Express-AM.
In the first half of 2001, the Government of the Russian Federation made a decision to partially finance the Express-AM program, which greatly changed both the pace of the project and the very possibility of its implementation. At the same time, the general contractor, NPO PM im. Reshetnev and subcontractors - Alcatel, NEC and Alenia Spazio. By the beginning of 2003, the schedule was finally approved.
The launch schedule was practically adhered to, which was not often the case in large space projects. Some delay in the launch of "Express-AM 1" was explained by the fact that for this spacecraft for the first time the Japanese company NEC Toshiba acted as a payload supplier instead of the already traditional for satellites - SE CS Alcatel Space. All 5 spacecraft of the Express-AM series are built on a platform developed by NPO PM. For four PNs it was manufactured by Alcatel, the supplier of PNs for the fifth one was NEC. Cooperation with the European company has already taken place, mutual understanding has been established. With the Japanese, it was necessary to rebuild cooperation. The processes of linking many issues related, for example, to standards, have dragged on, the launch dates for this spacecraft shifted.
This satellite was designed for both television and other communication services. VSAT networks can also operate on it. The device would be installed in the orbital position of 40 ° E, where the Express-A4 spacecraft was currently located, which after , as soon as NPO Reshetnev put "Express-AM 1" into operation, it would be moved to another orbital position. Now this plan was being worked out, there are several options. Presumably, as the most promising, the installation at 53 ° E, in which the "Express" was -AM 22", operating in the Ku-band. There was no C-band capacity, and the demand was quite high. This need can be met by the C-band capacity of the Express-A4 satellite.
The first launch of the satellite was successfully carried out on December 29, 2003 from the Baikonur Cosmodrome.
On April 27, 2004, the Express-AM 11 satellite was successfully launched from the Baikonur Cosmodrome. It was the second of a series of five Express-AM satellites launched as part of the program for updating the domestic civil orbital constellation. "Express-AM 11" was designed to provide a wide range of telecommunications services: digital television and radio broadcasting, Internet access, data transmission. The service life of the satellite was defined as 12 years.
However, in March 2006, the satellite went out of order, which led to the cessation of broadcasting of a number of TV channels, including federal ones, the disconnection of cellular communications and Internet access in vast areas of Siberia and the Far East. Within a few hours, the consequences of the accident were eliminated. According to experts, the cause of the failure was the collision of "Express-AM 11" with "space debris".
The capacity of the C-band of "Express-AM 1" would be fully loaded almost immediately, because NPO Reshetnev would transfer users from "Express-A4" to the new satellite. There was a lot of interest in Ku-band capacitance. There are no contracts signed today, but there are a number of applications. This was a common practice - it was rare that customers sign a contract before they are sure that the machine works. But NPO Reshetnev assume that the device would be loaded quite quickly and successfully. If you look at the previous devices, then the AM-22 was loaded by more than 70%, while NPO Reshetnev believe that 80% was the maximum load for the spacecraft. NPO Reshetnev need to have free capacity to respond flexibly to customer requirements. AM-11: Ku-capacity was almost fully loaded. And in the C-band today 30% was loaded.
The Express AM-1 satellite was launched into the target orbit with the help of an upper stage at 8:45 Moscow time on October 30, 2004. A representative of the Roscosmos Command Post told Interfax "All the systems of the launch vehicle and upper stage worked normally, in the normal mode". This was the third spacecraft in the Express-AM series, created by NPO Applied Mechanics under a contract with FSUE Kosmicheskaya Svyaz. NPO PM's subcontractor for the payload module for Express-AM1 spacecraft was the Japanese company NTSpace.
The satellite "Express AM-1" was created by the Research and Production Association of Applied Mechanics named after Academician Reshetnev (NPO PM). It would be used to provide a package of multiservice services (digital broadcasting, telephony, videoconferencing, data transmission, broadband Internet access), as well as to develop communication networks based on VSAT small station technology. Satellites of the Express-AM series are included in the Russian Federal Space Program for 2001-2005. "Express-AM" was the most powerful domestic spacecraft of this class. They are intended for qualitative renewal of the Russian orbital group. The service areas of Express-AM satellites cover not only Russia, but also other countries.
The Express-AM5 spacecraft was created on the basis of the Express-2000 heavy satellite platform. The mass of the apparatus was 3400 kg, including the mass of the payload - 1030 kg. The satellite has 10 antennas and 84 transponders (devices that automatically receive and send signals) capable of broadcasting in the C-, Ku-, Ka- and L-bands.
The satellite operates in geostationary orbit at an altitude of about 36 thousand kilometers above the Earth - in this position, the angular velocity of the satellites coincides with the speed of the Earth's axial rotation, as a result of which the satellite "hangs" over the same part of the planet. This position was most advantageous for communication satellites. The operating point of the Express-AM5 device was 140 degrees east longitude, which makes it possible to provide telecommunication services to the regions of the Far East and Transbaikalia. The term of active existence of "Express-AM5" reaches 15 years.
The Express-AM5 spacecraft was created by JSC Information Satellite Systems named after Academician M.F. Reshetnev" together with MDA Corporation (Canada) and Federal State Unitary Enterprise "Scientific Research Institute of Radio". Purpose: TV and radio broadcasting, data transmission, multimedia services, telephony, mobile communications. The satellite was launched on December 26, 2013. The operation of the Express-AM5 telecommunications satellite was limited due to the failure of the liquid cooling circuit of the satellite's thermal control system, the press service of the Federal State Unitary Enterprise Kosmicheskaya Svyaz reported. As reported by Kosmicheskaya Svyaz, on 03 June 2023 at 4:30 Moscow time, the liquid cooling circuit of the Express-AM5 satellite's thermal control system failed, which led to the excess of the threshold thermal operating modes of the spacecraft.
"In order to avoid overheating of the satellite and maintain its operability, the RSCC together with JSC "ISS named after M.F. Reshetnev" developed and implemented a number of measures to maintain the operability of the spacecraft. In accordance with the operational documentation and recommendations of the chief designer of JSC "Reshetnev", some of the transponders were turned off After that, the satellite continued its work, but the availability of its payload was partially reduced," the company said.
On Express AM-8 the first digital terrestrial multiplex includes Channel One, Russia-1, Match! TV, NTV, Channel 5, Rossiya K (Culture), Rossiya-24, Karusel, OTR (Public Television of Russia), TV Center and radio stations Radio of Russia”, “Mayak” and “Vesti FM”. It was noteworthy that the broadcasting began from the westernmost satellite from the Federal State Unitary Enterprise "Cosmic Communications" - "Express AM-8", which was located at the position of 14 degrees west longitude. It also broadcasts the German-language version of the Russian international TV channel RT, which was banned for broadcast in Germany, and the Arabic TV channel Al Manar TV. The broadcast of the first Russian multiplex on Express AM-8 has its own peculiarities. First, it was broadcast in full. open - Channel One, Russia-1 and Match! TV" are not encoded in the SUD Gostcrypt. Secondly, the broadcast was in the Ku-band, which practically simplifies the reception of a packet on antennas of reasonable diameters.
Express-MD
"Express-MD1" was created by the M.V. Khrunichev by order of the Federal State Unitary Enterprise "Space Communications" (GPKS) within the framework of the Program for the renewal of the Russian state civil satellite orbital constellation and the Federal Space Program of Russia (FSP) for the period 2006-2015, approved by the Decree of the Government of the Russian Federation of October 22, 2005. "Express-MD" was developed taking into account the forecasts for the development of the market for satellite communications and digital television and radio broadcasting in Russia. The payload for MD1 was supplied by the Italian division of Thales Alenia Space.
The joint launch of two Russian communication and broadcasting satellites Express-AM44 and Express-MD1 took place on February 11, 2009. From the Baikonur Cosmodrome, the satellites were successfully launched directly into the target geostationary orbit by the Proton-M launch vehicle with the Breeze-M upper stage and placed at the orbital position of 11°W and 80°E, respectively. This was the first joint launch of the Express-AM spacecraft with a small communication spacecraft of the Express-MD series.
In-orbit tests of the Express-MD1 payload module were carried out in full and with positive results. On May 12, 2009, the MD1 satellite was put into operation as part of the Russian civil satellite constellation, which was operated by FSUE Kosmicheskaya Svyaz (GPKS). The satellite resource was currently fully loaded by users.
Express-MD1, weighing 1140 kg, was the first "small" communication and broadcasting satellite in the RSCC orbital constellation. The satellite was designed to solve the problems of mobile presidential and government communications, to provide digital television and radio broadcasting services, access to the Internet, data transmission, video conferencing. MD1 was equipped with eight C-band transponders (band 40 MHz) and one L-band (band 1 MHz).
When creating a platform for Express-MD1, the specialists of the M.V. Khrunichev took into account the features of the launch - the simultaneous launch of two satellites into orbit, the medium Express-AM44 and the small Express-MD1. For the MD1 spacecraft, on which the heavier AM44 weighing 2560 kg was installed, specialists from the Khrunichev State Research and Production Center developed a reinforced platform.
With the joint launch of Express-AM44 and Express-MD1, the Proton rocket for the first time delivered a payload weighing 3,700 kg directly into geostationary orbit. In addition, Proton has successfully demonstrated a unique scheme for diluting spacecraft that are launched into different orbital positions.
To launch satellites, a modernized Proton-M launch vehicle with increased payload capacity was used. This rocket successfully demonstrated its capabilities for the first time when the DirecTV 10 super-heavy commercial communications satellite (weighing over 5800 kg) was launched in July 2007.
Express-RV
According to the state company Space Communications, by 2025 a new constellation of communications satellites should appear in a highly elliptical orbit, which will be able to cover up to 90% of the earth's surface. As part of the Sphere project, Express-RV spacecraft will cover areas of the Far North, providing communications to trains, river boats and trucks in the most remote, hard-to-reach areas. Express-RV satellites will be especially useful for providing high-quality communications in the Northern Sea Route area. Stable access to the Internet will be provided to ship crews, scientists, military personnel, specialists and employees who often have to move from place to place.
An urgent task in the Russian Federation is to ensure stable satellite communications in high-latitude and hard-to-reach areas of the Far North and the Arctic. This issue is studied in detail, where it is shown that the most economical and acceptable method from the point of view of electromagnetic compatibility (EMC) is the use of satellites in highly elliptical orbits. Geostationary orbit (GSO), with all its undoubted advantages, has two serious drawbacks: it does not provide service to areas above 76–78 degrees. north latitude and the viewing angles of the satellite from Russian territory are small, which makes it difficult to organize communications with moving objects.
Non-geostationary systems with satellites in medium and low circular orbits, also capable of solving the problem of communication in the Arctic, require significant capital investments amounting to many billions of US dollars (especially low-orbit systems), while the likelihood of a return on the funds spent is extremely low. It is also not entirely clear how to ensure EMC with GSO systems. The communication system with satellites on the VEO is capable of successfully solving the problems of providing communications to the Arctic zone, communications with mobile objects and a number of other important government tasks. At the same time, the capital costs of creating the system are several times lower than for low-orbit systems, and EMC with geostationary systems is guaranteed to be ensured without taking any additional measures.
The need for fixed satellite communications is determined by the tasks of servicing the Northern Sea Route, the needs of the local population, the creation of infrastructure in the Arctic zone for the development of mineral resources and ensuring the protection of Russian interests in the Arctic. To organize communications in the territory of a remote settlement, manufacturing enterprise, or rotational camp, a VSAT satellite station is installed, which becomes an access point to a remote information resource. In the area from the station to the direct user, modern means of wireless access can be used. Users of this satellite broadband access system could be local administrations, government agencies (Ministry of Emergency Situations, Ministry of Internal Affairs, Ministry of Transport, Ministry of Defense, various federal services), corporate users (geological exploration, oil and gas production, telemedicine, distance learning), monitoring services in the interests of various departments .
For a number of years, the State Enterprise “Space Communications” has been studying the issues of creating a satellite communication system (SCC) “Express-RV” using spacecraft on a VEO. The system is designed to solve the problems of providing mobile communications for government consumers throughout Russia, including the Arctic zone, organizing broadband networks on mobile platforms (airplanes, ships, railway transport, cars) also throughout the Russian territory, providing fixed-line communication services in the Arctic zone, where Geostationary networks do not work. As a possible option, a satellite direct audio broadcasting (DSB) network can be deployed in the system.
There are known constellations in the Molniya orbit consisting of two, three and four satellites. In a four-satellite constellation, the satellites are located in four orbital planes, spaced 90 degrees apart, and pass over the same ground points, that is, they have a common path. This grouping is called iso-route, and it is very convenient for organizing communications. In such a grouping, the duration of the working section is 6 hours
In a three-satellite constellation with a working segment duration of 8 hours, coverage of the territory of Russia and the Arctic zone with high elevation angles is also provided, but the altitude of the NRU/KRU point is reduced to 23 thousand km. A constellation of two satellites does not provide coverage of the Russian Federation at high elevation angles. Taking this into account, a standard four-satellite constellation with an orbital plane spacing of 90 degrees was selected for the Express-RV system. In the future, it is necessary to plan two similar satellite constellations (western and eastern) to fully service the northern regions of Russia.
An assessment of the required throughput, based on the results of marketing research, indicates that the task at hand can be solved by a middle-class spacecraft. The most suitable for this project seems to be a spacecraft based on Russian-made geostationary space platforms, which must be modified for operating conditions in a Molniya type orbit.
A new task that Russian specialists have to solve is to ensure the functioning of the spacecraft for a long period of time, at least 10 years. Domestic satellites that previously operated on VEO had a shorter active life and widely directional antennas, and therefore did not require very precise orbit correction. In the Express-RV system, maintaining constancy of orbital parameters is very important; this makes it possible to lower the requirements for the retargeting limits of subscriber antennas and ensure guaranteed visibility from the Moscow region of the spacecraft in the working section of the conjugate orbit. Two key parameters are subject to correction: the perigee altitude must be maintained within 1000 ± 10 km, and the latitude argument must be maintained within 270 degrees. ± 0.1 deg. This precision is made possible by the use of economical electric correction motors.
Audio reception in a car, as the experience of the American broadcasting system SiriusXM Radio has shown, requires significant capital expenditures for the creation of a satellite segment and a lot of organizational work to integrate the subscriber terminal into mass-produced cars. For Russia such a system is too expensive and does not pay for itself over the life of the satellites due to insufficient purchasing power of the population.
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