gps example of how gps works (global positioning system)

GPSGPSExample of how GPS worksExample of how GPS works(Global Positioning System)(Global Positioning System)

There are 24 satellites in orbit around the earth.

Suppose one knows that he is 625 miles from Boise, Idaho.

That is the only informati

on he has.

Does he know

where he is?

Now, suppose he knows that he is 690 miles from Minneapolis, Minnesota.

Now, does he

know where he is?

Now, let’s add that he knows that he is 615 miles from Tucson, Arizona.

Now, does he know where he is?

GPS Satellites put out a signal three dimensional, not two dimensional like the flat circles, so it creates a sphere.

Because it creates overlapping spheres the GPS unit can tell elevation in addition to longitude and latitude.

Satellites circling the earth.

1 2 3 4 5 6 7 8 9 10

a

b

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d

e

f

g

1 2 3 4 5 6 7 8 9 10

a

b

c

d

e

f

g

Cartesian Coordinate System

Vocabulary:Vocabulary:

•CITO- Cache In Trash Out

•Waypoint- Reference point for a physical location on earth

•Muggled- The act of vandalizing or stealing a cache

•Travel bug- A trackable tag that may be attached to a item in a geocache

•GPS- Global Positioning System

•Coordinate- Any of the magnitudes that serve to define a position of a point

•Geocaching- A world wide game of hiding and seeking treasures

•BYOP- Bring your own pen/pencil