Pre-Syncom Communications Satellite Studies–Dr. Boris T. Subbotin, Jack Fisher

All who have worked at the Hughes Space and Communications Group know of the Syncom development by Dr. Harold Rosen and his key team members, Don Williams, Tom Hudspeth and Dr. John Mendel. There is however, a somewhat earlier company activity in communications satellites that remains relatively unknown. A study was performed by the Communications Systems Laboratory (CSL) of the Aeronautical Systems Group under the direction of Dr. Samuel G Lutz. Dr. Lutz, the laboratory manager, was well known to Hughes management. In 1956 and 1957 he had formulated his thoughts on satellite communications and presented them to Hughes management. In late 1957 a Space Communications Group was formed within CSL devoted to satellite communication study and research. Except for a subcontract with Lockheed for the WS117L project this group was supported by Hughes general research funds.

Dr. Lutz obtained his PhD at Purdue University and was professor and chairman of the electrical engineering department at New York University from 1945 to 1951 before he joined Hughes. He directed Hughes communications engineering from 1951 to 1958. In 1958 he become a senior scientist at the Hughes Research Labs where he directed studies of satellite communications and regularly consulted with Harold Rosen. In 1962 he was named chief scientist at the Research Labs. He worked, lectured, and published numerous papers and articles on communications and satellites. He focused on future issues such as applications, technologies, frequencies of operation, sharing of orbital locations, methods of increasing communication capacities, earth antenna sizes, modulations, link noise allocations, government policies, and international CCIR and CCITT regulations and coordination. In December 1960 at the California Academy of Science conference in San Francisco, he envisioned 360 geosynchronous satellites hovering 1º apart “enough to satisfy the worlds long-range communications for several centuries”. In July 1961 he published an IEEE paper on broadcasting by satellites directly to home television receivers, perhaps the first time that this possibility was recognized. In 1973 Dr. Lutz was honored by the IEEE Communications Society, along with Claude Shannon, with the Edwin Armstrong Achievement Award.

In the few years just following the launching of Sputnik in October of 1957, this country was in turmoil. Many activities were initiated in reaction to the USSR “threat”. The Advanced Research Projects Agency (ARPA) was founded in 1958 and many space projects were being considered. The first ARPA project was SCORE, an Atlas missile launched into a 32 degree inclined elliptical orbit with a communications payload that could receive, record, and transmit messages. Score was launched on December 18, 1958 and its batteries lasted 12 days.

Echo was a 100-foot diameter Mylar balloon originally devised by NASA Langley to study the effect of atmospheric drag and solar pressure on satellite orbits. John Pierce at Bell Labs realized that Echo might serve as a passive communications satellite by reflecting microwave signals from and back to the Earth. Echo was launched August 12, 1960 by a Thor Delta and successfully relayed messages and data across the U. S. The Hughes Communications Division later designed and built the Passive Satellite Research Terminal (PSRT) AN/FRC-40 60-foot experimental ground station for Echo and installed it in 1963 at the Rome Air Development Center in New York.

The Hughes study, “Satellite Communications, An Initial System for Global Communication Via Satellite Relaying,” is documented in a brochure written by the Communications Systems Laboratory personnel and Dr. Lutz. One key contributor was Donald Miller, who later in the 1960’s worked with Dr. Rosen’s group. The brochure is undated but apparently completed in early 1958. It described a system of satellite communications that could have been provided with 1958 technology. This pre-Syncom study was an attempt to indicate to the U. S. government and military that Hughes had the interest, resources, and technical breadth to conduct the analysis, design, and construction of communication satellites.

The orbit selected for this study maintains the satellite apogee (maximum altitude) of an elliptical orbit continuously over the northern hemisphere to maximize time available for communications for the most populous regions. This type of orbit was later selected for the first USSR domestic communications satellite, Molniya, launched in 1965, and thus became known as a Molniya orbit. By selecting an orbital inclination at 63.4 degrees the apogee would remain fixed over the northern hemisphere and with a period of 12-hours the Molniya satellite could provide 8 hours of communications service.

The Hughes 1958 study adopted a Molniya-type orbit with a period of 4.8 hours, an apogee of 9500 miles, and a perigee of 500 miles as limited by the launch vehicle capability of that time. With a modest initial investment, it was projected that the satellite could be placed in service within one year. Available launch vehicles limited the satellite to 125 pounds. The selected VHF frequencies were 143 MHz uplink and 133 MHz downlink within a government allocated band. Downlink performance was based upon the 10 watt transmitter and a 0 db gain omni satellite antenna. The bandwidth of 100 KHz would be comparable to the capacity of TAT-1, the new transatlantic cable of 1956. The result was a simple straightforward system with readily available components for both the satellite and ground elements. The launch vehicle selected was a Thor ballistic missile, launched from Vandenberg AFB, with a second stage of six Aerojet 890-pound solid rockets. The third stage was a single Aerojet rocket and would remain integral with the satellite when expended. The satellite was spin stabilized, with no onboard propulsion capability so that the accuracy of the achieved orbit was entirely dependent upon the launch vehicle guidance. The solar power was 36 watts average with a 25 pound nickel-cadmium battery pack.

The system included three satellites and four ground stations, each with a 60-foot parabolic tracking antenna. The estimated total cost was $6.4 million including the launch vehicles and four launch attempts. The launch facilities at Vandenberg AFB were assumed to be government furnished.

The study also identified the ultimate synchronous orbit system with fixed ground antennas. It recognized that a single geosynchronous satellite and fixed ground antennas could be simpler and superior for global coverage. Such would have to await technology developments and launch vehicle capability improvements.

The Syncom development in 1959 under Dr. Harold Rosen was progressing independently. Before Hughes invested corporate funds in its development, Dr. Andrew V. Haeff, Vice President of Research, formed an independent task force to evaluate the Syncom design with Dr. Lutz as chairman. The other members were Donald Miller, Ed Felkel, Dr. Harold Rosen, and J. H. Striebel. The task force report in October 1959 was unanimous that the Syncom development was feasible. In 2008 Dr. Rosen stated “The resulting Lutz report enthusiastically made the case for the communication satellite venture that would be funded and operated by Hughes.” Hughes subsequently funded the Syncom development. Further satellite studies by the Communications Division of ASG were discontinued.







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About Jack Fisher

Jack was a systems engineer at Hughes from 1961 to 1992. He contributed to various programs including Surveyor, Pioneer Venus, Galileo, Intelsat VI and innumerable proposals. He was the manager of of the Spacecraft Systems Engineering Lab until his retirement. Upon retirement Jack taught systems engineering at a number of national and international venues.

4 thoughts on “Pre-Syncom Communications Satellite Studies–Dr. Boris T. Subbotin, Jack Fisher

  1. This is a fascinating piece of communications satellite history that I was previously unaware of. I worked at Space & Communications from July 1972 to April 2005 but I was unaware of any such work preceding Harold Rosen’s and Don William’s work that culminated in the early Syncom missions. The first program I supported was Westar I.

  2. I unintentionally omitted Tom Hudspeth from my reply. If possible please correct this error before posting.

  3. Herman Potocnik, Arthur Clarke, Samuel Lutz and Harold Rosen all foresaw the benefits of synchronous orbits. Great minds run in similar directions, even if these four worked independently of each other. We benefitted from working in the presence of giants.

  4. I feel that I was very fortunate to have been one of the team members who spent a few weeks in the Communications Division in Bldg. 110 at the Airport site working on the AN/FRC-40 prior to going to Rome, NY in April of 1962 for the installation and testing of the terminal. We used the terminal to track Echo 1 and later to track Echo 2 after it was launched. This terminal was the very latest in state of the art technology. There was a liquid helium cooled maser LNA. The antenna was a 60 foot diameter driven by hydraulic motors capable of five degrees/second movement.
    I remained at the Rome installation until July of 1964.

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