Geosynchronous Earth Orbits

The Soviet use of geo-synchronous satellites for telecommunications purposes did not begin until the mid-1970's. By the end of 1994 more than 100 communications and data relay spacecraft had been placed in geo-synchronous orbits with 36 still operational near 27 positions along the geo-stationary ring. During 1993-1994 a total of 12 GEO communications spacecraft were deployed under six programnames: Raduga, Gorizont, Kosmos, Luch, Gals, and Express. The last two represented the maiden flights of the next generation Russian GEO communications spacecraft.

Russian GEO spacecraft differ from most other GEO satellites by their greater mass (22.5 metric tons in GEO), their lessor communications capacity, and, until 1994, their lack of north-south station-keeping ability. The last characteristic is evident in the continual variation of orbital inclinations (typically between 0-5 degrees) of Russian GEO satellites during their operational lifetimes. To minimize this effect, new satellites have been launched with initial GEO orbital inclinations of 1-2 degrees under strict conditions which take advantage of solar lunar perturbations first to reduce the inclination to zero over a period of one to two years before it increases. East-West station-keeping is accomplished with liquid propulsion or ion thrusters.

To date, the development of all Russian GEO communications satellites has been directed by the Applied Mechanics NPO under the leadership of Mikhail Reshetnev. The Radio NPO and the Institute of Space Device Engineering are the primary communications payload developers, and the Astra NPO is the principal supplier of ground stations and receivers. Although USSR/Russian satellites are often characterized by short lifetimes in comparison to analogous Western satellites, these Siberian made spacecraft exhibit normal mission lives of 5-10 years. All GEO satellites are transported to Baikonur for launch by the Proton boosters. With rare exceptions the spacecraft are inserted into GEO near 90 degrees E and allowed to drift east or west to their intended stations.

SOVIET APPLICATION OF SPACE TO THE ECONOMY

By Lani Hummel Raleigh*

1971-1975

THE SYNCHRONOUS COMMUNICATIONS SATELLITES

1. Kosmos 637, Molniya 1-S, and Kosmos 775

On March 26, 1974 , the U.S.S.R. launched its first 24-hour synchronous satellite—Kosmos 637. The satellite was probably designed to study problems of launch and stabilization.

The Russians launched their first synchronous orbit communications satellite—Molniya 1-S—on July 29, 1974 . The spacecraft w-as placed in an equatorial orbit 35,850 kilometers high with a period of 23 hours 59 minutes and an inclination of 0 degrees 4 minutes. The equatorial orbit was chosen in order to give coverage to Eurasia , Africa , and Australia . Molniya 1-S is probably a prototype for the Statsionar communications satellite. Statsionar satellites would be used in an international consortium known as Intersputnik (see below).

On October 8, 1975 the Russians launched their third synchronous orbit satellite, Kosmos 775. It has been suggested that Kosmos 775 could also be a precursor to the Statsionar; however, its mission has not been positively identified.

2. Statsionar/Raduga

According to notifications submitted by the U.S.S.R. to the International Frequency Board of the International Telecommunications Union , the Soviet Union plans to launch three geostationary communications satellites over the Indian Ocean during 1975-76, primarily for coverage of the U.S.S.R. and Eastern European countries. Notification for Statsionar-T was published June 9; notifications for Statsionars 2 and 3 were published September 9.

Statsionar-T is intended for television broadcasting within the territory of the Soviet Union . A station located at Gus-Khrustalniyi, near Moscow, will transmit to a network of community-reception Earth terminals situated in the eastern regions beyond the Urals, in Siberia and the extreme north of the U.S.S.R. Statsionar-T will be placed in an orbit at 99 degrees East Longitude. Earth-to-space uplink will be 6.2 GHz ± 12 MHz. Downlink will be 714 MHz ± 12 MHz.

Statsionar 2 will provide communications services to Europe and the western portion of the U.S.S.R. It is designed for telephone, telegraph, and photo-telegraph communications and for sound broadcasting and television program transmissions. The satellite will be placed over eastern Africa at 35 degrees East Longitude. Earth-to-space uplink will be 5.75-6.2 GHz. Downlink will be 3.42-3.87 GHz.

Statsionar 3 will be essentially identical to Statsionar 2. It will function in the same frequency bands and have the same technical characteristics. However, Statsionar 3 will serve the U.S.S.R. exclusively except for the extreme north and Kamchatka , a peninsula north of Japan . The satellite will be located at 85 degrees East Longitude. (14)

Later, the Russians disclosed plans to launch a global satellite communications system consisting of seven geo-stationary Statsionar spacecraft positioned over the Indian, Pacific, and Atlantic Oceans . The Statsionar system would operate in the 4-6 GHz bands and would duplicate the coverage of the global system of the 91-nation International Telecommunications Satellite Organization. The ma]'or difference between the two systems is the type of Earth terminal used. The Statsionar satellites would operate with smaller and cheaper Earth terminals, equipped with 30-foot (9-meter) diameter antennas, and the standard antennas operating with the Intelsat space segment are 90-100 feet (27-30 meters) in diameter.

Statsionar 4 is planned for launch in 1978-79. Its coverage would extend from the Mid east and the U.S.S.R. to the eastern half of the United States and Canada in the Northern Hemisphere and would include all of Africa and South America in the Southern Hemisphere. The satellite would be stationed at 14 degrees West Longitude. The frequency range of Statsionar 4 for the Earth-to-space uplink is 6-6.25 GHz, The downlink is 3.6-3.9 GHz.

The planned position for Statsionar 5 is at 58 degrees East Longitude over the Indian Ocean . It would have a potential coverage of most of the Soviet Union , that portion of Europe not covered by Statsionar 4, the Mideast and Africa . Statsionar 5 is scheduled for launch in 1978-79. Its uplink frequency would be from 6-6.25 GHz. Downlink would be from 3.67-3.9 GHz.

Statsionar 6 will be positioned at 85 degrees East Longitude over the Indian Ocean . The satellite will have two transmit antennas, both concentrating coverage in the Northern Hemisphere. According to Soviet plans, one of the antennas will cover most of Europe, the western half of the U.S.S.R. and the northern segment of the Mideast . The second antenna will expand transmit coverage to the northern half of Africa and the eastern U.S.S.R. Reception capability would include signals from Earth terminals in the Southern as well as the Northern Hemisphere. The areas of reception capability would include approximately one third of the Earth's surface, from near the north and south polar regions through central Africa on the west and Australia on the east.

The planned position of Statsionar 7 is at 140 degrees East Longitude over the Pacific Ocean . It will transmit to the eastern area of the U.S.S.R. and areas southward in the Northern Hemisphere, but the reception antenna will extend this coverage area into the Southern Hemisphere to near the south polar region.

Statsionar 8, scheduled for launch in 1980, is supposed to be positioned at 25 degrees West Longitude over the Atlantic , and will cover an area in the Northern Hemisphere extending from the eastern portion of the U.S.S.R. to mid-Canada and the United States . The uplink frequency band would be from 5.75-6 GHz. The downlink frequencies would be from 3.42-3.67 GHz.

Statsionar 9 is supposed to provide Northern Hemisphere coverage of most of the U.S.S.R., Europe , Africa and the Mideast . It is scheduled for launch in 1980 and will be positioned at 45 degrees East Longitude over the Indian Ocean .

Statsionar 10, which is also planned for 1980 launch, will be positioned at 170 degrees West Longitude to provide transpacific coverage. (15)

Reportedly, from the U.S.S.R. notification on the Statsionar system it is evident that there is a possibility of frequency interference problems with the Franco-German Symphonic satellite now operating over the Atlantic and the two satellites Indonesia plans for its domestic system, scheduled to become operational in 1976, as well as several Intelsat satellites. Thus, the problem of radio frequencies will have to be resolved before the full Statsionar system becomes operational. (16)

On December 22, 1975 the Russians announced the launch of a new stationary communications satellite named "Raduga" (rainbow). It is assumed that Raduga is another name for the first satellite launched in the Soviet Statsionar series. It has also been speculated, but not confirmed, that Raduga or Statsionar-1 is in fact the same Statsionar-T satellite referred to earlier.

References:

(A) SOVIET SPACE PROGRAMS, 1971-75, OVERVIEW, FACILITIES AND HARDWARE MANNED AND UNMANNED FLIGHT PROGRAMS, BIOASTRONAUTICS CIVIL AND MILITARY APPLICATIONS PROJECTIONS OF FUTURE PLANS, STAFF REPORT , THE COMMITTEE ON AERONAUTICAL AND SPACE .SCIENCES, UNITED STATES SENATE, BY THE SCIENCE POLICY RESEARCH DIVISION CONGRESSIONAL RESEARCH SERVICE, THE LIBRARY OF CONGRESS, VOLUME – I, AUGUST 30, 1976, GOVERNMENT PRINTING OFFICE, WASHINGTON : 1976.

12. Pravda, Moscow, October 29, 1967, p. 3; Radio Moscow, No. 10, pp. 16-17 ; Elektrosvyaz', No. 11.

13. Radio Moscow , No. 10, October 1967, pp. 18-16. This source discusses more technical aspects of the circuits than is presented here. See also Elektrosvyaz', No. 11, 1967, pp. 4-8.

14. Aviation Week and Space Technology, New York , September 22, 1975 , p. 17.

15. Aviation Week and Space Technology, New York , December 15, 1975 , p. 16.

16. Ibid., p. 15.

• Ms. Raleigh Is a physical sciences analyst In the Science Policy Research Division, Congressional Research Service, The Library of Congress.