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Module Navigation:

1. Introduction

2. GPS Resources

3. GPS Quiz

4. GPS Crossword Puzzle

5. Presentation

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Glossary of Terms

 
   
 

Glossary of Terms

Atomic clock
A precision clock that depends for its operation on an electrical oscillator regulated by the natural vibration frequencies of a beam of cesium atoms.
Control segment
The five ground stations that continually check the satellites for proper function. 
Geomatics
The science and technology of gathering, analyzing, interpreting, distributing and using geographical information.
Geographic Information Systems (GIS)
Technology that analyzes, stores, and displays both spatial (altitude, political boundaries, etc.) and non-spatial (population, etc.) data about a place.
Global Positioning System (GPS)
A navigational system using satellite signals to fix the location of a receiver on or above the earth's surface.
GPS Receiver
Electronic equipment that passively receives GPS signal for processing.  A receiver may be hand-held or permanently mounted on a vehicle.
Latitude
Angular distance north or south from the earth's equator measured through 90 degrees.
Longitude
The arc or portion of the earth's equator intersected between the meridian of a given place and the prime meridian and expressed either in degrees or in time.
Navigation
The method of determining position, course, and distance traveled.
Satellite
A manufactured object or vehicle intended to orbit the earth, the moon, or another celestial body.
Sextant
An instrument for measuring angular distances used especially in navigation to observe altitudes of celestial bodies.
Space segment
The 24 satellites, each in its own orbit 11,000 miles above the Earth, that are responsible for signaling precise location and time data.
Spoofing
Sending a fake GPS signal.
User segment
The handheld (or mounted) receivers that process the signals from GPS satellites (space segment).  This segment gives the user the actual data in terms of location, and speed.