In today's world there are many strata to society.  We weave in and out of different groups and different levels during our daily lives: Community, family, business associations. Technology impacts society in its ability to enhance and uplift our lives through science, medicine, housing, connectivity, and the creation of clever/helpful everyday objects.

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Biography of Leona Seufert

GLOBAL POSITIONING SYSTEMS -

LOCATING THAT NEEDLE IN A HAYSTACK PART 1

A TV ad for OnStar has Batman pressing a button on his Batmobile, then a woman's voice asks "What can I do for you, Batman?". He requests the location of the nearest gas station. She gives him the location. How did she know where the Batmobile was located? GPS (Global Positioning System) technology gave her the precise location of the car!

What is GPS?

GPS  was developed in the 1970s by the US department of Defense. In 1982, as part of the government's effort to sell its technologies for commercial use, it was declassified and made available to the general public. The first devices created using this technology were large, difficult to program and understand. However, over the years as technology made miniaturization possible and the full potential of using GPS was better understood, many easier to use devices were produced.

The technology

GPS is a worldwide navigation system using a constellation of 24 satellites and their ground stations. In geo-synchronous orbit (maintained as stationary over a location) above the earth at a distance of 11,000 miles, they provide detailed positioning information. Devices using GPS locate 3 satellites to triangulate a particular position and one to measure altitude above sea level. The calculation of positions are accurate to a matter of meters. Advanced GPS can make measurements to better than a centimeter! To triangulate, a GPS receiver measures distance using the travel time of the radio signals from the satellites. A great deal of the system's accuracy is based on timing. Each satellite has an on-board atomic clock that is accurate to within 1 second every 70,000 years. For a very good detailed explanation of how this all works, go to  http://www.trimble.com/gps/

Pinpointing your location

The first adaptation of GPS technology for civilian use was for devices that could help you pinpoint your location. Today, they are palm sized and portable. Garmin and Magellan are the 2 large companies best known for producing these devices.

One of Garmin's hand-helds has a feature that will reverse your track log and help you navigate your way back home. Sort of like letting out a string then rolling it up to find your way back. Another device, the Rino,  integrates radio functionality to provide two-way communications. It can send communications up to five miles and can "beam" your exact location to another Rino user within a two-mile range.

Some of the handhelds have mapping capabilities. Garmin's eTrex Vista combines a basemap of North and South America, with a barometric altimeter and electronic compass. The compass provides bearing information while you're standing still and the altimeter determines your precise altitude.

From Magellen you can add GPS to your Palm Pilot. "Whether your are in the urban canyons of the city or deep in the country, attach the lightweight GPS Companion to your Palm m500 series and you'll always know where you are and where you're going to within a few meters." states the product description.

PC Magazine http://www.pcmag.com/article2/0,4149,758346,00.asp has a nice summary of these devices that help keep you from getting lost. "The devices in our roundup weigh from about 5 to 9 ounces with the batteries installed. Each device ships with built-in memory. The least-expensive devices-such as the Garmin eTrex ($120 street)-have less than 1MB of on-board memory. This type of receiver has no built-in maps and can only record your position and a few routes. At the high end, Magellan recently began shipping the Magellan Meridian Color ($499 street), the first standalone handheld GPS receiver with a color screen. The Meridian Color also comes with 16MB of built-in memory, and you can add from 8MB to 64MB of memory via an SD card."

Where's that package?

How does "Brown" (UPS) track your packages? Through the melding of GPS and a Geographical Information System (GIS). Vehicle tracking is the fastest growing use of GPS applications. Public transportation systems, delivery trucks, and courier services use everything from Java enabled mobile phones, special receivers, and modems to send the GPS location information back to the base GIS software. The software keeps track geographically of each vehicle's location. In the case of UPS and other carriers, the tracking is in real time meaning trucks' locations are constantly beamed to the home base software. Rotor Rooter uses Java enabled cell phones to locate the employee who is closest to a plumbing emergency. Publix Supermarkets uses its GPS enabled GIS software not to track a person but to plot out a route that would be the fastest, most efficient way to deliver the groceries.

Tracking mobile assets

Another fascinating application of GPS is to track mobile assets such as video cameras,  projectors, video walls, and sound equipment. Renters of audio visual equipment experience a high degree of theft with items just 'disappearing'.  Staging events for high end entertainment requires renting thousands of dollars worth of these assets.

For asset tracking worldwide to be possible and effective, the tracking device must be very small(chewing gum package size), use very little power, last a long time before battery recharge (3 months to a year), have low or reasonable cost, be sheltered from the elements (inside the container or sewn in a pouch/pocket, including the antenna), and be out of reach from outsider sabotage or tampering. So far this has been feasible for only large objects such as cars and transport containers. However, MicroNova Technology has developed a small enough device. Its GPS monitor combined with cellular coverage provides a consistent tracking of pharmaceuticals through their transport cycle. Other companies have developed solutions that shortly should  hit the market.

In Part 2 will examine how GPS has made tracking humans possible along with some other unusual uses for this technology.

      c 2008 Leona M Seufert