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Collins' Role in U.S. Space Communications | |
Collins' work in radio astronomy centered on design of a precision tracking device known as the radio sextant. This provided an advanced navigation method for ocean vessels which was not affected by weather conditions. The first sextant, tested in the early 1950s, detected only energy from the sun, which restricted its effectiveness to daylight hours. However, as advances were made and a more sensitive antenna and receiver were developed, a sextant was built which could track both the sun and the moon. Lunar radiation is about 50 times weaker than that of the sun. Radio astronomy work at Collins also resulted in a highly significant scientific discovery in the late 1940s. With this and other radio propagation research, Collins entered the space age with perhaps as much knowledge as any company had in space communications. From this start the company has continuously been deeply involved in space and space-related communication activities. |
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![]() Image 1: The first photo to be transmitted via a man-made satellite (Echo I)) was of President Dwight D. Eisenhower on August 18, 1960. |
A brief summary of such activities includes: The most widely known of these space activities is Collins' participation in the Mercury, Gemini and Apollo manned spacecraft programs. |
Even before Gemini flights were underway, plans were launched for the Apollo moon-landing program, and Collins, as a subcontractor to North American Aviation, was assigned responsibility for the complex communication and data subsystem aboard the spacecraft. Far more complex and with vastly increased capability over the previous manned spacecraft systems, the Apollo system utilized unified S-band to combine two-way voice and telemetry, ranging, and the down link TV signals in a single transmission method. The system had its most significant test on the moon-circling Apollo 8 mission, when millions of persons throughout the world marveled at the clarity of radio communication and live TV from 240,000 miles out in space. |
In addition to unified S-band, the Apollo system includes VHF equipment for near earth communication, and for the Command Module to Lunar Module communication link. The VHF method is similar to that used in Mercury and Gemini. Equally as necessary and important to the Apollo program as the spacecraft system is the network of unified S-band ground tracking/communication stations, for which Collins was prime contractor to NASA's Goddard Space Flight Center. That contract required the design, equipping and installation of 14 stations in all, 11 of them with 30-foot diameter antennas and three with 85-foot diameter antennas, the latter serving as the deep space link on lunar missions. In addition, equipment was provided for tracking ships. Leading up to such an achievement was years of previous experience and capability in tracking stations and the electronics for maintaining contact with satellites in orbit or traveling to other planets. Between 1958 and 1963 Collins provided a total of 11 space tracking stations. First of these was at the 85-foot dish antenna facility of the Jet Propulsion Laboratory, at Goldstone, Calif., which has been used in many of America's deep space satellite probes. Collins supplied all major equipment except the 85-foot reflector, mount and hydraulic servo mechanism. Not only the electronic equipment but also buildings and access roads were provided by Collins, a pattern repeated in many other station projects. |
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Following the Goldstone installation was another tracking station in Puerto Rico, used to track down-range flights of missiles from Florida. Image 4 Other NASA installations include Rosman, North Carolina; Fairbanks Alaska; Newfoundland, and Australia. Including the Unified S-band network, Collins has installed or participated in work on more than 25 space tracking/communication stations throughout the world. Collins' research activities and facilities have added much to space tracking and communication knowledge. The facilities include a 60-foot diameter parabolic reflector at Dallas, erected in 1962 and used since then to investigate many aspects of satellite communication. |
One of the latest stations, near Moree, New South Wales, Australia, was equipped and built under contract to the Australian Overseas Telecommunication Commission. Equipped with a 90-foot diameter antenna, the station provides a satellite communication link for Australia with North America and Asian nations. At full capacity, the station has the capability of transmitting and receiving 600 voice channels and one television channel simultaneously. Among early space communication research activities of Collins was a moon relay in 1951, a project involving the company and the National Bureau of Standards. Another area of study which provided extensive data on tracking was the work of Collins involving the Echo I inflatable balloon satellite. Echo I, which had a considerably longer life than originally expected, was tracked by Collins engineers at intervals for nearly three years. Measurement of signal strength and variations in the signal as Echo passed in range of the Cedar Rapids tracking station indicated changes in the balloon's size and shape. Collins conducted experiments with Echo in 1960 which included live voice communication between Cedar Rapids and Dallas via the satellite, and transmitting a wire-photo picture of President Eisenhower. Echo research yielded valuable data on orbital variations, acquisition and tracking of a satellite, and radio propagation from earth into space. In the cases of both the moon bounce and the Echo experiments, transmissions were the first ever made between distant points on earth via a man-made satellite or the moon. Collins did considerable work starting in the 1950s on providing components and guidance and control systems in several U.S. missile programs. The Collins' Autotune® was adapted for use in several of these. |
![]() Image 4: Silhouetted against a darkening sky, a 30-foot diameter dish used in the Apollo Unified S-band network. |
![]() Image 5: Tests are conducted on the voice control center of Gemini space carft voice communications system designed and manufactured by Collins. |
Among programs in which the company participated by developing and producing systems or partial systems were the Bomarc, Sergeant, Terrier, Nike-Ajax, Atlas and Firebee missiles. Communication systems linking stations within the Atlantic and Pacific Missile Ranges, and equipment to assist in tracking of those facilities, is another area of extensive activity in the space field. Collins antenna systems and high frequency equipment, as well as microwave systems, are employed for communications between launch control centers and downrange stations. America's most massive and comprehensive rocket-spacecraft preparation and launching facility is the Launch Complex 39, at Kennedy Space Center, Fla. This is where the giant Saturn-V rocket stages are assembled, the Apollo spacecraft sections are mated with the rocket, and the entire vehicle is transported to the launch pad and sent on its space journey. Basically the Complex 39 includes the gigantic Vehicle Assembly Building, the control center for checkout and launch, the crawler-way, mobile launch towers and service tower, and two launch pads. To tie all the facilities together, aversatile intercommunication system was developed and installed by Collins throughout the 39 facilities of the Launch Complex. Consisting of some 2,000 operator stations and coaxial cable links, the system is called RADIC (for Radio Interior Communication). In addition to manned spacecraft communication systems, Collins has familiarization with unmanned satellites through systems supplied for Explorer series satellites, specifically two of them for which Dr. James A. Van Allen of the University of Iowa was responsible for instrumentation. The lnjun Explorer satellites carried command receivers and antenna systems designed by Collins. Image 6. |
Another space communication area in which Collins has done a great deal of work to gain detailed engineering knowledge is in use of VHF frequencies for communication via satellite. Use of this method is advocated in many aviation circles for long range air to ground or air to air communication, particularly for flights over oceans. Collins has collected extensive data through use of a test package installed on airline jet freighters on regular flights, including trans-Pacific flights. Data obtained by recording transmissions between the aircraft and ground stations via a synchronous orbit satellite is analyzed to obtain necessary equipment design and operational information. For the past two years Collins has been involved in developing a series of UHF ground terminals for use in a joint military service tactical satellite communication program. |
Known as TACSATCOM, the program involves delivery of terminals ranging from a one-man alert receiver to a three-man team pack, vehicular configurations, and airborne and shipboard systems. The terminals will be used by the military services to test and evaluate communication by satellite relay for tactical situations. Also Collins is currently working as a major subcontractor on the communication system for the U.S. Air Force Manned Orbiting Laboratory (MOL) program. The era of the missile, the satellite and manned space flight has depended upon and stimulated knowledge in nearly every area of science and technology. Equally important with all other disciplines for space exploration is communication. Collins has furnished and continues to provide significant contributions to space communication. |
![]() Image 6: Robert E. Johnson. Langley Air Density /lnjun Explorer technical project engineer, views spacecraft mated to Scout launching vehicle. A Collins antenna was used on the lnjun Explorer satellite. |
—Collins Signal, Issue 69, Volume 17-2, 1969 - Pages 13-20 |