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2.2
Evolving Satellite Coverage
Once Hughes, NASA, and COMSAT proved that GEO satellites were the wave of
the future, it remained a difficult task to bring the first systems into practical
existence. That was the role of the global satellite operators, along with regional
and domestic systems. All three demonstrated that GEO satellites could fill a
wide variety of telecommunications needs, in line with the advantages of satellite
communications outlined in Chapter 1.
2.2.1
Global Service: INTELSAT, PanAmSat, and Orion
Clearly, the first and most demonstrable need for the commercial satellite was to
provide international communications links across the oceans. At the beginning of
the international GEO satellite era, most telecommunications companies around
the world were government owned or controlled (with the exception of North
America). In time, a trend toward privatization and even competition appeared,
which eventually affected the structure of international satellite operation. The
following paragraphs outline the evolution of the now well-established international
satellite system.
2.2
Evolving Satellite Coverage
43
2.2.1.1
Early Bird
In March 1964, COMSAT contracted with Hughes Aircraft Company for the
construction of two spin-stabilized satellites using C-band (SYNCOM used S-band,
which was authorized only for NASA experimentation). Early Bird, the well-
recognized name for this first commercial satellite, was launched on a McDonnell
Douglas Delta rocket in the spring of 1965. The satellite worked perfectly for six
years, well past its design life of two years. The second spacecraft was never launched
and now resides in the Air and Space Museum of the Smithsonian Institution in
Washington, D.C. Early Bird was positioned over the Atlantic Ocean and was first
used to link stations in Andover, Maine, and Goonhilly Downs, England, providing
voice, telex, and television service. Having gained such renown,
bird
continues to
be used as a nickname for all GEO satellites.
2.2.1.2
INTELSAT
The intended international nature of the system led the U.S. government and
COMSAT to establish a new organization in 1964 called the International Telecom-
munications Satellite Consortium (INTELSAT). Later,
Consortium
was changed
to
Organization
, and INTELSAT grew to become the preeminent satellite operator
in the world. The INTELSAT Agreement, a treaty among member countries, was
signed in 1971. COMSAT continued as the U.S. signatory, while the Government
Post Office (now British Telecom) fulfilled that role for the United Kingdom. In
time, INTELSAT evolved into more of a business, purchasing spacecraft based
on the global demand for telephone and TV services and other noninternational
applications. INTELSAT was completely privatized and is currently owned by
private investors.
This quasi-governmental approach served INTELSAT and the world commu-
nity well for more than three decades. The signatories and their respective users
employed the capacity to implement international telephone and TV links to aug-
ment terrestrial transmission means like fiber optic cable and microwave links.
One important application is the use of INTELSAT links for fiber optic cable
restoration. This was used again when an earthquake off of Taiwan severed several
cables. In 1984, INTELSAT introduced the INTELSAT Business Service (IBS), for
business communication private lines. In some countries, corporate users could
install and operate their own Earth stations for direct access to the INTELSAT
space segment. The service became very popular, because it was based on digital
transmission and the pricing was attractive relative to public leased lines. INTEL-
SAT then proceeded to digitize all its international telephone links, resulting in the
extensive use of intermediate digital rate (IDR) carriers. The widespread use of
IDR carriers at capacities of 2 Mbps and higher improved the efficiency and quality
of telephone services over INTELSAT satellites. INTELSAT followed a deliberate
process to establish the requirements for its satellites and to procure them from
manufacturers. Each generation of spacecraft, indicated in Figure 2.3, was marked
by a significant upgrade in capability.
The big step up in satellite capability happened with the introduction of the
Hughes Aircraft-built Intelsat IV (Figure 2.4), a spacecraft many times larger than
its commercial forerunners. A major innovation came in the way the repeater and
44
Evolution of Satellite Communication
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