Dateline Asia
RUSSIA'S STATSIONAR SATELLITE SYSTEM
BY Mark Long
Originally appeared in the August, 1996 issue of SatFACTS
©1996 MLE INC. All Rights Reserved.
Back in the early 1980s, would be satellite TV enthusiasts living outside of North America found slim pickings in the skies overhead. In Europe, Africa and the Middle East, for example, the low power INTELSAT and Symphonie (France) satellites of that era carried only a few TV services. To get a viewable picture, one had to use a very big dish (4.5 meters in diameter or greater) as well as undertake periodic hand cranking of the antenna's actuator arm to keep those wobbling inclined orbit birds within the antenna's main beam. In the era just prior to the launch of the very first EUTELSAT Ku band satellite, about the only reasonably strong C band satellite TV signals in the European sky came from Russian satellites.
In 1982, a British entrepreneur hired me to bring over a satellite TV system from the United States to a communication show at the Wembley Exhibition hall in London, England. So I hopped on a British Air flight with a 3.7 meter ADM dish, a customised circular polarisation feedhorn, a 120 K Cal Amp LNB, and my own home brewed receiver tuned to Russian satellite specs. At Wembley, numerous members of both the public and the press stood around our stand, mesmerised by England's first large scale public showing of home satellite TV technology. But once their curiosity had been satisfied, the unanimous verdict of the audience was that no one would pay good money to pick up TV programs from Russian satellites.
Three years later, I found myself standing in the middle of the antenna farm at the Dubna uplink facility a mere 100km north of Moscow. As a gesture of good will just prior to Ted Turner's 1985 Goodwill Games in Moscow, the Soviet Union had granted my request to research some stories about Russian satellite TV for U.S. magazines and the newspapers of the Los Angeles Times Syndicate. My exhilaration at finally being at the source was inextricably entwined with bizarre experiences of being shadowed by Soviet agents who wanted to know just what I was really up to. I just want to watch satellite TV, Boris. Honest!
In the years between then and now, I've watched Russian satellites from a variety of obscure locations, from central Bolivia and the Rio Negro of Argentina, to the wilds of Papua New Guinea and northern Thailand. Following the fall of the Iron Curtain, the Russian satellite system rapidly opened up to customers from abroad. In the Asia/Pacific region alone, more than a dozen satellite TV channels owe their very existence to the Russian satellite system. What's more, it has never ceased to amaze me that satellites originally designed in the late 1970s would still be with us today, providing efficient, reliable service on a global basis. Best of all, the evolutionary changes in the Russian satellite system that are now in motion promise to further expand TV programming availability on a world-wide basis.
Russian Satcom Terminology
A certain amount of confusion reigns over the terminology often used to describe Russian satellites as well as Russia's global satellite system. The term STATSIONAR (Russian for stationary) refers to the orbital assignment for each satellite, regardless of the actual class of satellite in operation at any orbital location. Table 1 identifies the major STATSIONAR orbital designations along with their equivalent position in degrees of east or west longitude. Gorizont, Express, Raduga, Gals and SDRN are the names of actual different classes of Russian communication spacecraft now in geosynchronous orbit about the earth's equator.The term Loutch sometimes is encountered in the literature concerning Russian satellites. Loutch is the name of a Ku band satellite system for which Russia had filed with the International Telecommunication Union (ITU) many years ago. In actuality, however, there are no dedicated Loutch satellites currently in orbit. The Loutch Ku band communications payload, however, is carried aboard Gorizont and SDRN class satellites.
The Gorizont Satellites
For the past fifteen years, Gorizont (Russian for horizon) satellites have served as the reliable workhorse of the Russian satellite fleet. Today eleven Gorizont satellites provide a wide array of telecommunications services from numerous orbital assignments around the globe. These three-axis stabilised spacecraft feature a solar wing span of 9.46 meters which generates about 1,280 watts of power. Gorizont satellites, which weigh approximately 2,200kg, have a warranty life of 3 years and an estimated mission life of 3 to 5 years.
Gorizont satellites are not true geostationary spacecraft. Each spacecraft has an initial negative inclination of approximately -1.5 degrees (sometimes referred to as a reverse inclined orbit), which changes to a positive inclination at a rate of approximately 0.85 degrees per year. The use of negative inclination at the time of satellite deployment provides a period of almost two years in which TVRO antennas of 3 meters or less in diameter will not need to track the movements of the satellite as it meanders along the figure eight track of its inclined orbit. Long-time satellite observers have previously noted that Gorizont spacecraft have lacked a full time telemetry beacon, a common feature of most other commercial communication satellites. Normal Gorizont satellite operation is autonomous, i.e., each spacecraft operates automatically within predetermined parameters. Telemetry data is recorded aboard the satellite and routinely transmitted to Earth once or twice each month. If events occur which force the spacecraft to operate out of its normal operating limits, however, the spacecraft will immediately signal engineers down on the ground.
High power Global Beam from 142.5 degrees East
Gorizont Channel Characteristics
Each Gorizont spacecraft carries one Ku band (11.525 GHz centre frequency) and five C-band (3.705 to 3.945 GHz) transponders, each with a bandwidth of 38 MHz. The Ku-band transponder is powered by 20 watt amplifier, while the above mentioned C-band transponders are equipped with 15 watt amplifiers. Also available: one high powered, 75 watt C-band (3.675 GHz centre frequency) transponder with a bandwidth of 40 MHz. Gorizont satellites provide a total of four different C band coverage beams (17x17 degrees global, 9x18 degrees northern hemispheric, 6x12 degrees zone and 5x5 degrees spot) and one 5x5 degrees Ku band spot beam. Table 2 shows that selected C band transponders can be switched between one of two available coverage beams by ground command. Beam pointing for all coverage areas is fixed prior to the launch of each individual spacecraft and cannot be changed once the satellite is in orbit.Gorizont satellites downlink using right hand circular polarisation (except for the spacecraft at 130 and 142.5 degrees East, which downlink using left hand circular polarisation) in the C band frequency range and horizontal polarisation to downlink within the Ku band frequency spectrum.
Hemispheric Beam Coverage from 142.5 degrees East
The Express Satellites
On October 13, 1994, the first of a new generation of Russian Express satellites was launched to 14 degrees west longitude over the Atlantic Ocean. The next Express satellite is scheduled to be launched in the near future to an orbital assignment of 80 degrees East. Express C-band transponders will provide wide beam coverage within an area ranging from central Europe and the Middle East to Japan and Australia, while two Ku-band spot beam transponders are expected to serve customers in India. Russia also has registered numerous additional STATSIONAR orbital positions with the ITU for the future assignment of Express spacecraft.Based on the reliable Gorizont satellite platform, Express satellites are three axis stabilised spacecraft which feature an expanded solar wing span of 21 meters which generates about 2,400 watts of power. Express satellites, which weigh approximately 2,500kg, also have an increased warranty life of 5 years and an estimated mission life of 5 to 7 years.
Express Channel Characteristics
Express satellites feature a highly sophisticated propulsion system which combines hydrazine and xenon plasma thrusters to achieve true geostationary operations. With the launch of Express, the orbital name STATSIONAR truly applies! Each Express spacecraft carries two Ku band (11.525 and 11.625 GHz centre frequencies) and nine C-band (3.705 to 4.145 GHz) transponders with a bandwidth of 38 MHz. The two Ku-band transponders are powered by 20 watt amplifiers, while the C band transponders have 15 watt amplifiers. Also available: one high powered, 75 watt C band (3.675 GHz centre frequency) transponder with a bandwidth of 40 MHz.Express satellites provide a total of four different C band coverage beams (19x19 degrees global, 15x15 degrees quasi global, 5x10 degrees zone and 5x5 degrees spot) and one Ku band spot beam. Table 2 shows that selected C band transponders can be switched between one of two available coverage beams by ground command. Beam pointing for the C band zone as well as the C and Ku band spot beams can be individually steered by ground command.
Express satellites use circular polarisation in the C band frequency range and linear polarisation within the Ku band frequency range. Express satellites transmit to Earth in the C band using right hand circular polarisation. Horizontal polarisation is used to downlink signals in the Ku band.
Gorizont Ku-band Spot Beam from 142.5 degrees East
Raduga, Gals, Ekran & SDRN
Raduga satellites are C band only spacecraft which operate within an expanded 3.45 to 3.95 GHz frequency spectrum. Raduga class satellites do not carry the high power C-band spot beam capabilities of the Gorizont and Express satellite classes and therefore are primarily used for the transmission of voice and other narrow band traffic. Raduga satellites are in operation at 12, 35, 45, 49, 70, and 85 degrees East.Gals satellites are Ku band only spacecraft originally developed for DBS operations. Two Gals spacecraft currently are collocated at 71¡ East, where they transmit into eastern Europe via high powered spot beams within the 11.7 to 12.25 GHz frequency spectrum. Like Express, Gals spacecraft are true geostationary satellites.
Ekran satellites, which operate within the UHF frequency spectrum (700 to 780 MHz), are used to provide community TV services to remote locations in central Russia. Operating in the lower end of the Ku-band frequency range, SDRN satellites are used for communications links with the MIR space station.
INTERSPUTNIK
The largest single user of Russian Gorizont satellites is INTERSPUTNIK, an international satellite communication organisation founded in 1971. Headquartered in Moscow, INTERSPUTNIK uses about thirty transponders on Gorizont (40, 80, 96 103, 130 and 142.5 degrees East), Express (14 degrees West), Raduga (70 and 85 degrees East) and Gals (36 degrees East) satellites. What's more, additional transponders on many of these satellites remain available for lease by INTERSPUTNIK to member and non-member organisations alike. While INTERSPUTNIK uses a total of one Gorizont and three Express transponders to transmit voice and other narrow band traffic, the vast majority of its transponders are used to transmit TV services.In September of 1995, INTERSPUTNIK announced its agreement to operate two Gorizont spacecraft (Gorizont 41 at 130 degrees East and Gorizont 42 at 142.5 degrees East) which Rimsat, Ltd. of the United States had previously leased from the Russian Space Agency. A total of ten transponders on these two spacecraft alone are currently used to transmit TV program services to broadcasters and cable TV systems located in India, Laos, Papua New Guinea and elsewhere within the region.
The INTERSPUTNIK VIII Project
In 1995, INTERSPUTNIK announced the approval of the INTERSPUTNIK VIII project which calls for the manufacture, launch and operation of two new-generation satellites over the Indian and Atlantic Oceans. Preliminary plans call for the two spacecraft to be placed at 75 degrees East and 16 degrees West, respectively. Plans call for the first satellite to be manufactured by November of 1998 with the second satellite to follow by May of 1999.The C band payload will feature wide shaped transmit beams with a nominal EIRP of 37 to 40 dBW. The Ku band payload will transmit via steerable spot beams with a nominal EIRP of 48 to 53 dBW.
(Editor's Note: In June of 1997, Lockheed Martin announced that was entering into a joint venture agreement with INTERSPUTNIK to form a new global satellite system. The new company, known as Lockheed Martin Intersputnik or LMI, has its headquarters in London and a separate sales office in Moscow.)
