Global Positioning Systems
Jessie Fowls
Boise State University
Operations Management – 345
Topics That Will Be
Covered
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GPS definition
Brainstorming Exercise
GPS basic breakdown
How GPS works
Real World Example
Application Exercise
Summary
GPS Definition
• Worldwide space-based radio
navigation system consisting of
as constellation of 24 satellites
and their ground stations.1
Brainstorming Exercise
• How could GPS be used in your
company?
• What areas of your company
would benefit most from GPS?
GPS Basic Breakdown
• Consists of 24 Earth-orbiting
satellites
• Solar cells power each satellite
• Antennas transmit timing info.
• Operated and maintained by U.S.
Department of Defense
GPS Basic Breakdown
• GPS Satellite Facts2
– Name: Navstar
– Altitude: 10,900 Nautical Miles
(12,660 Miles)
– Weight: 1900 lbs (in orbit)
– Size: 17ft. with solar panels
extended
– Orbital Period: 12 hours
GPS Basic Breakdown
• Three components
1) Space: Satellites
2) Control: Master Control Station
3) User Segments: Receivers
How GPS Works
• Five Logical Steps3
1)
2)
3)
4)
5)
Triangulating or Trilaterating
Measuring Distance
Getting Perfect Timing
Satellite Positions
Error Correction
How GPS Works
• Triangulation or Trilateration
– Using the distance of 3 satellites
measured from your position
anywhere on the planet
How GPS Works
• Trilateration Illustration
Suppose you knew you were
• 625 miles from Boise
• 690 miles from Minneapolis
• 615 miles from Tucson
How GPS Works
625 miles
690 miles
Boise
Minneapolis
Denver
615 miles
Tucson
• Determines your location to be
somewhere near Denver.4
How GPS Works
• Measuring Distance Coordinates of your location
– Longitude and Latitude
– Altitude
How GPS Works
• Getting Perfect Timing
– Radio Signal
– Atomic Clock
How GPS Works
• Satellite Positions
– High Orbits
– Careful Monitoring
How GPS Works
• Error Correction
– Types of error (slows signal)
• Charged particles in ionosphere
• Water vapor in troposphere
• Ground obstructions
How GPS Works
• Error Correction
– Minimizing Error
• Predicting delay
• Comparing signal speeds
• “Dual frequency”
Real World Example
• U.K. Coastal Erosion5
– Problem in past and
present
– GPS is used to prevent
destruction of structures
Real World Example
– Monitor coastline with GPS
– Technology used to predict risky
areas
– Information used for future
shoreline management planning
Exercise
• List some possible uses for GPS
in general.
• More specifically, for what types
of things might your company
use GPS?
Summary
• GPS: Global Positioning Systems
– Determines precise location anywhere on Earth
• Uses advanced technology and an easily
understandable method for calculating
location.
• Can be used in nearly every aspect of
business, environment, recreation,
education, etc…
Summary
“GPS is to position
what the clock
was to time”6
Bibliography
• “All About GPS” http://www.trimble.com/gps
• “Global Positioning System.” Microsoft
Encarta Encyclopedia. 2002 ed.
• Hartman, Julie. “Combination of
technologies improves coastal erosion
measurements.” Civil Engineering Oct.
2001: 33-35.
• “How GPS Receivers Work”
http://www.howstuffworks.com/gps.htm
• Kaplan, Elliott D. ed. Understanding GPS:
Principles and Applications 1st ed.
Boston: Artech House, 1996. 487.