GPS Tracking

As we have learned, the Global Positioning System is operated by the National Executive Committee for Space-Based Positioning, Navigation & Timing. These three eponymous capabilities have always been the core benefits of GPS in its simplest iteration, but the staggering amount of applications that have proliferated within this past decade have been much more varied, constrained only by the limits of human ingenuity. At the intersection of unprecedented technological innovation and decades of policies that have stimulated the growth of GPS, this simple tool has become an omnipresent and nearly invisible part of our daily lives.

On www.gps.gov, the official federally hosted informational Web site, possible applications run the gamut from roads and highways, rail, marine and aviation to agriculture, public safety and disaster relief. These illustrate the tremendous capacity that GPS has for serving the public interest by making infrastructure more efficient and responsive. Numerous cities have come to rely on geographic information systems, or GIS, which use GPS technology to collect data and synthesize it into useful information used to make important municipal decisions, from drainage plans to emergency vehicle routes. GPS is also a critical component of Intelligent Transportation Systems, communication-based technologies that use real-time data to manage traffic flow. (more…)

At the turn of the 21th century, Global Positioning Systems finally began reaching its full potential as it burst on to the technological scene with truly practical applications for the new millennium.

A National Policy for GPS

With the NAVSTAR at Full Operational Capability by April 1995, GPS was beginning to capture the attention and imagination of the international community. On March 16, 1995, President Bill Clinton issued a letter to the International Civil Aviation Organization restating the United States’ commitment to providing GPS capability to civilians around the world.

In 1996, Clinton went even further by issuing a formal policy directive that ensured GPS’ future as a dual-use system. The policy review was conducted jointly by the White House Office of Science and Technology Policy and the National Security Council and issued as a directive of the National Science and Technology Council. The goals of the policy were outlined as follows:

1. Strengthen and maintain our national security.
2. Encourage acceptance and integration of GPS into peaceful civil, commercial and scientific applications worldwide.
3. Encourage private sector investment in and use of U.S. GPS technologies and services.
4. Promote safety and efficiency in transportation and other fields.
5. Promote international cooperation in using GPS for peaceful purposes.
6. Advance U.S. scientific and technical capabilities.

Under this policy, management of GPS capability was divided among three national agencies. The U.S. Department of Defense would continue to acquire, operate and maintain the basic GPS and coordinate with other agencies on national security implications of the technology. The U.S. Department of Transportation took the lead in all federal civil GPS matters and the development of transportation and commercial applications. The U.S. Department of State would work with foreign governments in assessing bilateral or multilateral guidelines on the provision and use of GPS services and coordinate interagency reviews of international agreements.

The policy authorized the creation of an Interagency GPS Executive Board, jointly chaired by the departments of defense and transportation, to help integrate the needs and findings of all of the involved agencies and act as a consultant for U.S. governmental agencies, industries and foreign governments. (more…)

­­­­­Initial Challenges of GPS Development

Almost immediately after launching, the Global Positioning System faced serious obstacles to continued growth and development. The biggest hurdle was financial. Although GPS technology received support from all branches of the military, it was not a standard weapons system, and its function was not as straightforward and well-defined as other military research opportunities vying for government dollars. In 1979, the Office of the Secretary of Defense (OSD) slashed the program’s budget by about 30 percent. As a result, the satellite design was significantly scaled down, and the plan for a 24-satellite constellation was temporarily reduced to 18. The development of Block IIs, the next generation of modern GPS satellites, was placed on hold. From 1980 to 1982, the program was altogether eliminated until the OSD rallied for its continued survival. The joint program office, a collaboration of the U.S. military branches overseeing GPS research, also argued for the importance of the technology in military applications by emphasizing the advantage of increased bombing accuracy.

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Today Global Positioning System technologies have become integrated into our daily lives, whether we know it or not. Dozens of new gadgets flood the market each month boasting GPS capability; they come embedded in cars, boats, airplanes, construction machinery, farm equipment, even your mobile phone and laptop computer. Its functions are simple and necessary: navigation, tracking, surveying, timing – the same basic tasks conducted by civilizations for centuries, only now they have become immensely faster, easier and more precise than ever. As the technology becomes more and more a part of the fabric of our routines, it is easy to overlook the spectacular journey GPS has made from its breeding ground in military applications to today’s high-tech consumer toys.

The infrastructure supporting GPS technology is surprisingly simple, yet also technically complex in its precision and ingenuity. Since 1994, all GPS capabilities have been supported by a constellation of at least 24 satellites, each measuring about 17 feet across and weighing approximately one ton, that are part of a global navigation satellite system. Powered primarily by solar energy, they circle the earth at an altitude of more than 12,000 miles and speeds of around 7,000 miles an hour, completing two orbits in less than 24 hours. The satellites emit microwaves that allow GPS receivers to determine their exact location, speed, direction, and time through triangulation of the signals. Officially named NAVSTAR, the GPS constellation took the government more than $12 billion to build and costs roughly $750 million a year to maintain, a price tag that includes satellite replacement and research and development. In the last decade, the number of actively broadcasting satellites has grown from 24 to 31, arranged in a nonuniform pattern, which provides redundant measurements and improve reliability and availability of the system.

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