geostationary telecommunications satellites electronic telephone set ...

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forever silent. The next launch attempt
was made that July. Everything worked
perfectly on Syncom II, and communications
was successfully demonstrated
via a synchronous but not geostationary
satellite (since the orbit was
inclined relative to the equator). The
first geostationary orbit was achieved
in 1964 with the launch of Syncom III
into an equatorial synchronous orbit;
among other things, it carried television
transmissions of the Tokyo Olympics
across the Pacific.
Coincident with the first Syncom
launch, the U.S. Comsat Corporation
was formed for the purpose of engaging
in commercial communications
via satellite. Noting the success of
Syncom, Comsat entered into a contract
for the construction of an experimental
operational satellite of similar
design to be used in transatlantic
service by INTELSAT, the International
Telecommunications Satellite Consortium
(now Organization), which would
be formed in time to use the new satellite.
In the spring of 1965, Intelsat I,
also known as Early Bird, was launched
and inaugurated commercial intercontinental
communications of voice,
telegraph, and television traffic via
satellite.
While Early Bird was being constructed,
NASA was sponsoring the development
of still higher performance
satellites in its Applications Technology
Satellite series. Additional communications
capacity could be achieved
by using pencil beam antennas to
replace the lower gain toroidal beam
heretofore used. The ATS satellites
demonstrated both electronic and
mechanical means of despinning these
beams to illuminate the earth continuously
from the spinning satellite. The
ATS satellite also took the first pictures
of the full disc of the earth from synchronous
orbit by use of a spin-scan
cloud camera. Early Bird was followed
in 1966 by Intelsat II, a larger and
slightly higher capacity satellite, and
in 1968 by Intelsat III, which featured
a mechanically despun pencil beam
antenna and completed the first truly
global system for INTELSAT with yet
higher capacity.
In 1969 an experimental high
power
satellite designed to provide service
to ships and airplanes was launched
by the U.S. Department of Defense.
Called TACSAT, it featured a new dual
spin configuration which provided
greater flexibility in the communications
and mechanical design areas
than the earlier spinners by relaxing
some of the geometric constraints.
The method of stabilizing this configuration
was invented by Anthony
lorillo. This design feature was incorporated
into the high capacity Intelsat
IV series which began service in 1971,
and whose six currently operating satellites
carry the bulk of INTELSAT'S
traffic. The Intelsat orbiting fleet is at
present being augmented by the still
further advanced and higher capacity
Intelsat IVA, two of which have been
launched within the last few months.
The additional capacity of Intelsat IVA
was achieved by the development of a
multibeam antenna with east-west
isolation, which makes it possible to
reuse the frequency spectrum. The
antenna, its feed distribution system,
and the transmitter compartment are
today's standard for satellite engineering.
The Intelsat satellites currently
carry all transoceanic television and
most of the international telephonic
communications, in conjunction with a
complex of 123 earth stations located
in 71 of the 92 member nations of IN­
TELSAT.
As the economy of communications
via satellite steadily improved through
technological change in the Iate1960's,
it became apparent that not only international
but also intranational communication
could be achieved on a cost
competitive basis by use of satellites
in certain countries. Canada became
the first country to implement a national
satellite system with the inaugural
use of Anik by its Telesat Corporation
in 1972. The large antenna used
on Anik generated an antenna beam
which concentrated much of the satellite's
radiation within the borders of
Canada, thus providing substantial
communications capacity via a relatively
small and low cost satellite. The
three Anik satellites now provide dual
language television distribution and
thin-route telephonic service to the
sparsely populated portions of Canada,
as well as conventional communica-