Global Positioning Global Positioning SystemsSystemsGPS Units:

Development to Modern Uses

Getting to Know Your GPSGetting to Know Your GPSNotes Notes NotesNotes Notes Notes

Draw a Diagram in your notes

Label each of the buttons

Label each button with one function

-What do they do?

What is GPS?What is GPS?Notes Notes NotesNotes Notes Notes

Satellite based navigation system-satellites orbit Earth twice a day

U.S. Department of Defense in the early 1980’s

-first satellite launched in 1978

NAVSTAR-official governmental name for

GPS

How Does a GPS Work?How Does a GPS Work?•Satellites transmit data to Earth receivers

-You are holding a receiver!•Triangulation used to pin point location

-very similar to our method on the map!Notes Notes Notes

What really happens…1. Receiver compares time signal from when it was transmitted to when it was received

2. Time difference tells unit how far you are from the satellite

3. Distance relayed from several other satellites to receiverconfigures your position!

SatellitesSatellites• 24 orbiting 12000 miles above us

•Travel at speeds up to 7000 mph

•The more you use, the more accurate your data

• Powered by solar energy with backup battery -in case of solar eclipse!

•Stays on path using rocket boosters to adjust course

Would Your GPS Ever Let YOU Would Your GPS Ever Let YOU Down?Down?Clock errorsAtmosphereSolar FlaresRadiationAltitudeLarge buildingsNumber of

SatellitesAge of Unit

Military UsesMilitary UsesNavigation

Target tracking

Missile and projectile guidance

Search and Rescue

Reconnaissance and Map Creation

The GPS satellites also carry a set of nuclear detonation detectors

Scientific UsesScientific Uses Notes Notes NotesNotes Notes Notes

Surveying

-accurate data much fasterMapping

-accurate elevation, lat. & long. quicklyEmergency Management

-receiver in phones so can be located by dispatcher

Monitoring Tectonics

-measure actual distance moved during an earthquake

Uniform time

-transmits data via time measurements, very precise

Prices…Can Everyone Get Prices…Can Everyone Get One?One?Civilian

ranges from $100 to $500

Survey ranges from $1000 to $5000

MilitaryWho knows!

* You could spend as much as you wanted!

Review…What Have You Review…What Have You Learned?Learned?