"Basics of the Global Positioning System (GPS) " INTRODUCTION I. ATTENTION GETTER: From this spot in the classroom to the Eiffel Tower in France is a distance of xx miles. How do I know this? With the assistance of over 20 satellites and my handheld receiver / display I can pinpoint my current position anywhere on earth, as well the direction and distance to any other place on the planet. This combination of satellites and receivers make up what is called the Global Positioning System, or GPS for short.

II. REASON TO LISTEN: Hundreds of thousands of people use this GPS system everyday From construction to aviation, the global positioning system provides precise tracking and navigation for an almost endless list of uses. Most likely in the future just about everyone will depend on this system, whether they have a permanent receiver in their car, a portable one like this they carry along, or even a small receiver that could be integrated into a watch.. CREDENTIALS: As a commercial pilot, I depend on this system everyday for aircraft navigation. I have become very familiar with both the operation and procedures involved in using this system.

IV. THESIS: I am now going to share with you some more information about GPS, demonstrate the operation of my receiver, and elaborate on who uses GPS and why. BODY I. MAIN POINT #1: First I want to discuss the history of the Global Positioning System and how it works. (Visual Aids - will show handheld receiver, and draw satellite-earth orientation on board) a.

History i. Originally started by the government for military operations in 1973 ii. In 1980 the Department of Defense authorized use for civilians (Ref #1) . In 1993 FAA approved GPS for aviation b. Infrastructure i. Composed of 24 satellites (Ref.

#2) ii. Land based antennas. Individual receivers (permanent and portable) c. How it works i. Satellites orbit the earth twice a day ii.

The receiver gets signals from the satellites (1575.42 MHz @ 50 W) (Ref #3) . Triangulating position iv. 3 satellites in view - 2 D, 4 satellites in view - 3 D d. Role of the receiver i. The receiver takes this information and determines a lat / long ii.

Database of unit superimposes position and puts it on a map display.. To find direction and distance to somewhere, plug in coordinates, or upload a database that has the coordinates stored in already. TRANSITION: Now that we know how the system works as a whole, I will now demonstrate how my personal receiver operates. II.

MAIN POINT #2: I will now show you some basic functions of my GPS. (Visual Aids - handheld receiver on projector) a. Passive system - works like radio in car, but must be line of sight b. Free to use, but receivers are c.

Satellite acquisition page d. "Direct to" function e. Route Planning i. Find fuel usage, time to destination based on speed and winds f. Information about airports i. Allows for better organization while flying -- safety g.

Points of Interest TRANSITION: After understanding the basics of the system, we will now look at its practical uses and who uses it.. MAIN POINT #3: Now I want to share with you why GPS has become so popular for navigation and precision tracking. a. Accuracy i. Can locate position within seven feet ii.

Could be more accurate, but the military limits this for national security. Talks of making it less precise after Sept. 11 (Ref #4) b. Who uses it? i. Aviation - can go directly to an airport 1. saves time and money (airlines) 2. more accurate than ground based nav systems 3. back up system for emergencies 4. allows instrument approaches into small airports that kept pilots out for bad water ii.

Construction use system for precise locating of buildings (Ref #5) . Military 1. don't need land nav aids in foreign territory 2. precise bombings iv. Personal Consumer 1. Direction Maps in luxury cars 2. Hikers in back country CONCLUSION I. SUMMARY / REVIEW: In closing, GPS is a rapidly expanding technology that was originally intended for military use, but is now used widespread in civilian applications. Handheld units such as this one, and permanent units installed in planes and cars, are becoming common place among the world.

The aviation industry has been the most benefited by GPS, which allows efficiency in navigation and increases safety. II. CLINCHER: Now that you know all about this interesting technology, you will probably see numerous applications in day to day life, whether you are on a cruise boat, or driving by a construction site. In fact, this technology is available to you right now since consumer electronic stores are now selling this equipment at reasonable prices.

If you take nothing else out of this, next time you are at a party, bring up the fact that the Eiffel tower is exactly xx miles from Clermont College, and believe me, everyone will be impressed.


1 - Klaus, Ray. "GPS". web June 1998 #2 - Robertson, Stuart.
How GPS Works". web May 2000.
3 -- web Garmin Ltd. Website #4 - Tennyson, Elizabeth. "Satellites, Signals, and You". web June 2001.