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How Does GPS Find Your Position?
Trilateration can be used to determine your location
on a map. Open your Web browser and go to http://
electronics.howstuffworks.com/gadgets/travel/
gps1.htm to view the article by Marshall Brain and
Tom Harris at How Stuff Works. Check out how three
measurements are being made to determine a single
location (like in the previous Michigan example), then
start Google Earth and zoom to your location. Use
Google Earth and its measuring tools to set up a similar scenario—find your location relative to three other
cities or locations and calculate the measurements
from each that are needed to trilaterate your position.
Hands-on Application 4.1
Trilateration Concepts
FIGURE 4.4 Using
distances from two points
in trilateration.
Traverse City
Ann Arbor
Ann Arbor
Flint
Lansing
150 miles
50 miles
FIGURE 4.5 The results
of trilateration (with
distances from three
points) to find a location.
Kalamazoo
Traverse City
Ann Arbor
Ann Arbor
Flint
Lansing
150 miles
50 miles
60 miles
How Does GPS Find Your Position?
Trilateration can be used to determine your location
on a map. Open your Web browser and go to http://
electronics.howstuffworks.com/gadgets/travel/
gps1.htm to view the article by Marshall Brain and
Tom Harris at How Stuff Works. Check out how three
measurements are being made to determine a single
location (like in the previous Michigan example), then
start Google Earth and zoom to your location. Use
Google Earth and its measuring tools to set up a similar scenario—find your location relative to three other
cities or locations and calculate the measurements
from each that are needed to trilaterate your position.
Hands-on Application 4.1
Trilateration Concepts
FIGURE 4.4 Using
distances from two points
in trilateration.
Traverse City
Ann Arbor
Ann Arbor
Flint
Lansing
150 miles
50 miles
FIGURE 4.5 The results
of trilateration (with
distances from three
points) to find a location.
Kalamazoo
Traverse City
Ann Arbor
Ann Arbor
Flint
Lansing
150 miles
50 miles
60 miles