Build It and They Will Come: The Far-Reaching Effects of Global
Positioning
by John Vardalas
For more than a
millennium after the fall of Rome, Western Europe’s existence
was one of great geopolitical uncertainty. Great land
empires to the south and east constantly threatened to overrun
Europe. Unable to advance its commercial, political and military
ambitions by land, Europe’s Atlantic nation-states turned to the
world’s oceans.
By the end of the 15th century, the Portuguese,
Spanish, Dutch and English were locked in a ferocious battle for
global maritime supremacy, in both trade and war. Superior
scientific and technological know-how in navigation and
cartography were great advantages in this competitive struggle.
The success or failure of maritime ventures depended on
determining location on the earth’s surface. Where am I in this
vast ocean? Where are the Spice Islands and other sources of
wealth? Where are the treacherous reefs and rocks? Where are my
enemies’ ships? Good answers led to personal glory and great
fortunes, while wrong answers often led to human tragedy or
financial ruin.
The intellectual
awakenings of the Renaissance, with its strong empiricist view
of knowledge, the irresistible seductiveness of fortunes to be
made from exotic products, and the mythical aura of distant
lands, created an unquenchable thirst for geographic knowledge.
Forgotten for nearly 1,200 years, Ptolemy’s methods and ideas of
mapping the globe were rediscovered. Astronomy and mathematics
enabled people to use the celestial bodies as the eternal
reference from which to calculate the latitude and
longitude of any place on Earth. Triangulation, for example,
enabled us to survey the planet and produce more accurately scaled
maps. For the first time, perspectives of the Earth were being
drawn. Globes of the earth started to appear. Mercator’s
projection was an invaluable boon to mariners. The need for
navigation and cartography led to more precise measuring
instruments. The search for a practical way to measure longitude
at sea helped drive improvements in clock technology. The
paradigms and methods of navigation and mapmaking then remained
pretty much the same until the mid-20th century, when a dramatic
change took place.
The Birth of
NAVSTAR
 Space
Race?
The Russian Federation Government operates the
Global Navigation Satellite System (GLONASS), a
21-satellite navigation system similar to the
United States' GPS. GLONASS is based on the same
data transmission and positioning methods as
GPS, and, in the eyes of some foreign airlines,
has one distinct advantage over GPS
— it isn't
owned by the U.S. military. GLONASS is operated
by the Coordination Scientific Information
Center (KNITs) of the Russian Federation's
Ministry of Defense.
For more information on GLONASS, visit:
www.glonass-center.ru |
|
|
In 1964, the U.S.
Navy deployed the satellite system Transit, the forerunner of
today’s global positioning system (GPS). By means of Doppler
shift techniques, Transit used seven low-altitude polar-orbiting
satellites to determine positions of Navy ships and ballistic
submarines across the world’s oceans.
During the same year,
the Navy
started work on a second, more sophisticated system called Timation. From the Air Force’s perspective, the Navy’s satellite
navigation system had critical limitations: location was
specified in only two dimensions, its coverage was not
continuous and its response time was too slow for fast-moving
jets. The Air Force set out to design its own system.
Prompted by cost
and the need for inter-service operability, the Department of
Defense (DOD) called for a coordinated approach. In 1968,
DOD established a tri-service steering committee called the
Navigation Satellite Executive Group
(NAVSEG). NAVSEG spent
several years hammering out a set of specifications — the number
of satellites, type of orbit, signal protocols and modulation
techniques — and developing cost estimates that all of the services
could accept. By 1973, the group reached a compromise, and in
1974, DOD started the long-term project to build the NAVSTAR
GPS.
Another 20 years
would pass before the GPS would reach its current configuration.
In 1994, the 24th and final satellite in the GPS was in orbit.
By 1995, DOD stated that it had spent
about $8 billion to develop and deploy GPS. To this day, DOD
still owns and operates the world’s global positioning system.
GPS’ 24 satellites lie
in six orbital planes and circle 20,200 km above the Earth in
12-hour orbits.
GPS can locate
position in three dimensions to within a few feet anywhere on
the globe. And while users need four satellites to fix a
position, the system has added redundancy; users can always
access at least five satellites from any point on the Earth’s
surface. GPS’ level of accuracy, immediacy of response and
geographic scale are historically unprecedented.
Build It and They
Will Come
These dramatic
quantitative improvements in precision, speed and scale opened
the door to profound qualitative change in society. DOD had
originally designed and built the GPS system to serve military
needs exclusively. But even before NAVSTAR GPS was fully
operational, the civilian market — predominantly the maritime
and aviation industries — was knocking on DOD’s door, asking for
access to the system. Few could have imagined the diverse
applications GPS could accommodate and the mass-market appeal it
could generate.
The mass appeal
of GPS is an unintended consequence of the military’s
willingness to risk great sums of money for the cause of
precision. Where am I? Where is it? Where are they? For the
Pentagon, answers to these geographic questions were essential
to the effectiveness of the command and control of America’s
worldwide military resources. An approximate answer was not good
enough. Location had to be given at the technical limits of
precision, available at any instant in time and for any
position on the planet. It is hard to imagine any profit-driven
institution, committing to spend billions of dollars to answer these questions. How could one ever get any
reasonable return on such a massive investment? Where was the
market to justify the great financial risks? But supply created
a demand. GPS is an excellent example of the movie cliché “build
it and they will come.”
DOD never had any
intention of inviting civilians to its “field of dreams.” But
after the Soviet downing of Korean Air flight 007 in 1983,
President Reagan agreed to make GPS available to the civil
aviation industry. In 1991, the United States made GPS available
on a continuous basis for civilian use around the world, without
charging any direct fees. To protect its strategic interests,
DOD incorporated a “selective availability” (SA) technique in 1990. SA was
the purposeful, random worldwide degradation of GPS’ accuracy in
the data available to civilians. But on 1 May 2000, President
Clinton signed an order that the intentional degradation of the
civilian GPS be discontinued. Overnight, the accuracy of GPS
offered to civilians increased by a factor of 10 and the
door to the mass market opened wide.
Far-Reaching
Impact
GPS' impact on economic activities such as civil aviation, commercial
maritime transportation, agriculture, surveying, mineral
exploration and environmental management has been considerable.
In addition to accurate positioning data, GPS also offers easy
and universal access to highly accurate timing signals. Rather
than maintaining private and expensive atomic clocks, users can
exploit signals from GPS to synchronize electric power grids to
data communications networks.
GPS use has also
found its way to recreation. The real-time availability of high
geographic precision has considerably improved boating safety,
has helped fishermen find their favorite spots on the water, and
has given hunters and hikers a new spatial awareness of the
wilderness. Golfers can now know the remaining
distance they need to reach the green. But perhaps the greatest
impact GPS has and will continue to have on society has come
from embedding precise spatial awareness in consumer items such
as cell phones and automobiles.
When used from a
conventional land-line telephone, 911 emergency services can
automatically pinpoint the origin of the call and ensure a quick
response. But a cell phone is not fixed to a particular address.
If cell phone users call 911, they often find it difficult to
specify their location. In 2001, the Federal Communications
Committee mandated that cell
phones be equipped with technology that would allow the 911
system to locate the caller. With SA removed, GPS offers the
solution. Beyond emergency services, GPS-equipped cell phones
have far greater effect on personal lives. For example, cell
phone users can get directions to their favorite restaurants or
other destinations quickly. Along similar lines, GPS offers
motorists real-time, speech-based driving instructions. As GPS
receiver prices drop, every car may soon be equipped with
sophisticated navigational electronics that will be able to
match up the driver’s position with a vast geographical database
of people, places and services.
Privacy Issues
Likely to Arise
With the
technological capability of knowing everyone’s position in
real time, important privacy issues will surely arise. There
will certainly be abuses. Real-time geographic precision, for
example, will
raise telemarketing to a new level of annoyance. Imagine having
your cell phone flooded with spam text messages and phone calls
every time you pass within a certain distance of a store eager
to promote its products. Beyond being an aggravating nuisance,
there are also questions of personal freedom. What legal
protection would citizens have from over-zealous law enforcement
agencies using cell phones to track people's movement?
For most of
history, the sun, moon and star-filled heavens offered humanity
an eternal reference frame. By the end of the 20th century,
satellites had displaced the celestial sphere. GPS is far less
romantic and mythic, but its societal impact may prove to be far
greater.
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