ACTS
Program Formulation
Background
Information
NASA
had a very significant role in the establishment of satellite
communications, first with the Syncom program to prove the
feasibility of the geo-synchronous orbit and later with
the ATS and CTS programs, which developed the C and Ku bands
and led to the establishment of the commercial satellite
communications industry. At this point, NASA directed its
efforts to other space endeavors, expecting that the industry
would continue the needed technology development to keep
the industry viable and competitive.

NASA’s
Re-entry into Communication R&D
In
1974, several organizations began to assess the consequences
of NASA's decision to essentially eliminate satellite communication
activities that focused on commercial applications [11].
The Electronic Industries Association (EIA) issued a position
paper in January 1974, which urged NASA to reconsider its
decision. In January 1975, the American Institute of Aeronautics
and Astronautics (AIAA) issued a similar report. It urged
NASA to re-enter the communication satellite field by sponsoring
new families of application technology satellites. The report
argued that from 1960 to 1973, "the federal government
took the dominant role in communication satellite research
and development, thereby providing the basis for low-risk
operational system development by private enterprise in
the 1960s and 1970s."

In
the fall of 1975, NASA asked the National Research Council
(NRC) to consider and report on the question: "Should
federal research and development on satellite communication
be resumed and, if so, what is the proper federal role in
this field?" To undertake the study, the NRC formed
a Committee on Satellite Communications, under the auspices
of the Space Application Board. After studying this question,
the consensus of the committee was that major advances in
communication satellite technology required government investment,
particularly in the areas where high technical risks were
involved. This committee concluded that satellite communication
R&D was an appropriate federal responsibility, and that
NASA should resume the research and development activities
needed to provide the new technology for future commercial
communication needs. The NRC committee recommended, in a
1977 report [12], that NASA implement an experimental satellite
communication technology flight program based on an assessment
of need, technology projections, and service concept development.
It recommended that the technical design of any NASA experimental
communication satellite should support several end user
service concepts, and that appropriate user groups should
assist in the conceptual definition of both the needed technology
and the experiments themselves.
Based
on the results of the NRC report, the increasing demand
for domestic voice, video, and data traffic, and the foreign
competition and prospects of trade disparity, President
Jimmy Carter saw fit to reinstate federal sponsorship of
communication satellite technology. Official sanction for
NASA to resume its responsibility was contained in the October
1978 Presidential Directive (PD-42). This directive stated,
"NASA will undertake carefully selected communication
technology R&D. The emphasis will be to provide better
frequency and orbit utilization approaches."
| The
NASA Satellite Communication Program for the 1980s |
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In
1978, as a result of the Presidential Directive, NASA began
the process of rebuilding its R&D activities in the
communication satellite arena [13,14,15]. The future technology
program was planned in cooperation with the National Research
Council's Space Applications Board Subcommittee on Satellite
Communications, whose membership consisted of leading common
carriers, spacecraft manufacturers, and representatives
of communication users.
Market
& System Studies
In
this first phase of the NASA program, market and system
studies were conducted to determine future service demand
and whether or not C- and Ku-band satellites could satisfy
it. Two contracts were awarded to common carriers: Western
Union Telegraph Company, and U.S. Telephone and Telegraph
Company, which was a subsidiary of International Telephone
and Telegraph (ITT) [16,17]. The emphasis of these studies
was to forecast the telecommunications traffic that could
be carried by satellite competitively. During this same
time frame, two other system studies were conducted: one
each by Hughes Aircraft and Ford Aerospace, with supporting
studies by TRW, GE, and the Mitre Corporation [18,19]. Their
purpose was to identify the technology needed to implement
cost-effective and spectrum-conservative communication systems.
The results were combined to define potential commercial
system configurations that could address the market for
trunking and customer premises services that was expected
in the early 1990s. System requirements derived from these
postulated commercial configurations formed the basis for
the technology development program that followed.
The
market studies predicted that rapid growth in domestic voice,
data, and video traffic would lead to a five-fold increase
in U.S. communication demands by the early 1990s. A combination
of these market projections and communication satellite
license filings with the FCC portended a saturation of North
American orbital arc capacity using the C- and Ku-band frequencies.
To relieve the pressure of this expanding market, the 30/20
GHz frequency band was needed. As a result, the new NASA
communication program for commercial application was named
the 30/20 GHz Program and was structured to:
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Develop
selective high-risk, 30/20 GHz technologies that focused
on relief of orbit and frequency congestion and developing
new and affordable services |
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Promote
effective utilization of the spectrum and growth in
communications capacity |
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Ensure
continued U.S. preeminence in satellite communications |

Satellite
Addressable Market Demand
The
technologies required to meet these objectives were judged
to be of such high technical risk that they were beyond
the capability of any one company to finance.
In
1979, NASA designated the Lewis Research Center (LeRC) in
Cleveland, Ohio, to be its lead center in planning and executing
the commercial communication satellite technology R&D
Program. In 1999, the Lewis Research Center's name was changed
to the Glenn Research Center (GRC), in honor of John Glenn,
astronaut and U.S. Senator from Ohio.
Early
communication satellite systems employed simple, bent-pipe
transponders with a single antenna beam to cover a large
region (such as the continental United States). The new
NASA program needed to develop technology that would allow
the frequency spectrum to be used more efficiently. One
technique to accomplish this was to cover the region with
many small spot beams so that the same frequency could be
reused simultaneously in non-adjacent beams. Such frequency
reuse increased the capacity of satellites by a factor of
five to ten times that of a single beam satellite, with
only a modest increase in spacecraft size, power, and weight.
The technology to accomplish this high degree of frequency
reuse employed antennas with high-gain spot beams and electronic
systems with onboard switching and processing to inter-connect
the spot beams. In addition, the high-gain antenna allowed
for smaller aperture user terminals at higher data rates.
This was the technology developed by NASA.
Single
Beam versus Multibeam Satellites
| Technology
Feasibility & Flight System Definition |
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In
1980, the program moved forward in two phases. The first
phase was to 1) continue the market studies to increase
confidence in the forecast for orbit saturation and 2) to
do proof-of-concept development of the identified technologies.
The proof-of-concept program was a laboratory (breadboard)
type of development to prove that the technologies were
feasible. Approximately $50 million was expended on the
first phase. If the first phase proved successful, the second
phase would consist of developing an experimental flight
system to demonstrate that the technologies could provide
reliable communications services.
The
first phase was fully supported by the entire service provider
and satellite manufacturing community. The second phase
of the program was the one that became controversial. The
service providers had great concern about how reliably the
technology would work in space, and therefore, argued for
a flight program. Some satellite manufacturers, however,
had reservations about proceeding with a flight program
because they felt it would give the winning contractors
of the NASA procurement an unfair competitive advantage.
This controversy continued throughout most of the life of
the ACTS program.
Program
Coordination with Industry
Two
industry committees were formed to guide the program. The
NASA Ad Hoc Advisory Committee was created to provide general
policy direction. The committee included notable representatives
of both the system supplier and service supplier industry.
Their contribution provided timely and sage review of the
program, as well as providing NASA with insight into the
industry philosophy relative to the roles and responsibilities
of both government and the private sector.
The
second industry committee was a Carrier Working Group (CWG),
consisting of representatives from all the major satellite
service providers. The CWG was charged with helping NASA
formulate the technology and flight system requirements,
develop experiments, and provide overall guidance. These
requirements and experiments were deemed necessary by the
CWG to demonstrate the readiness of not only the technology,
but of its service applications as well. Coordination was
also established between the Department of Defense and NASA,
especially in the development of various critical advanced
technology components.
Proof-of-Concept
Development
The
purpose of the proof-of-concept (POC) technology development
was to demonstrate the technical feasibility of the key
component building blocks [20,21]. The approach NASA used
was to issue multiple contracts to various aerospace and
related companies for the development of each high risk
technology: multiple spot beam antenna, base band processor,
TWTA, wide-band switch matrices, low-noise receiver, GaAs
FET transmitter, GaAs IMPATT transmitter, and ground antenna.
Duplicate awards for most of the critical technology components
were employed to increase the probability of successful
development, and to produce multiple sources for communication
hardware. In addition, multiple awards helped to ensure
that a variety of perspectives and technical approaches
were brought into each development. These contracts called
for the development of the technology, the construction
of POC versions of the components, and their testing in
the laboratory to verify performance.
The
POC hardware substantially reduced the risk associated with
the planned development of the flight system. Another product
of these technology contracts was the prediction of feasible
component, subsystem, and system performance levels. NASA
used these performance predictions to provide guidance for
follow on technology development. Service providers and
manufacturers could also use these predictions in planning
activities for the commercial system designs of the early
1990s.
The
Department of Defense (DOD) participated in the NASA POC
program. Several of the critical technology POC elements
that were of interest to the DOD were co-funded by DOD and
NASA. To enable the effective transfer of information that
was generated in the program, all contractors were required
to prepare task completion reports. These reports were presented
at periodic industry briefings (only for interested U.S.
parties) hosted by NASA.

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