1. GPS BASICS

2. What is GPS? Developed by Oklahoma 4-H

3. GPS  Global Positioning System  Network of 24 satellites (with spares)  Developed by Department of Defense  Operational 24 hours/day  Available worldwide  Land, sea and air  Works in all weather conditions  It is FREE!!

4. Satellite Constellation

5. Navigation Tools of the Past SextantChronometer

6. Beginnings  TRANSIT developed by Navy in 1960s  Used to track nuclear submarines  Air Force created own system  Used to locate vehicles on land or in air

7. NAVSTAR  Combined Navy and Air Force systems in 1973  NAVigation Satellite Timing And Ranging (NAVSTAR )  First used in combat during Operation Desert Storm – 1991  Full Operational Capability – April 27, 1995

8. GPS System  Space Segment – Satellite Constellation  Control Segment– Monitoring Stations and Ground Antennas  User Segment – Receivers

10. GPS Satellite

11. Satellite Information  Weighs approximately 2,000 lbs  Travels 7,000 mph  17 feet across with solar panels extended  Last 10 years  Orbit 12,500 miles above Earth  Circle the Earth twice daily

12. In the next lesson we will learn:  How GPS works  Coordinates – Latitude and Longitude  Creating and Finding Waypoints using a GPS receiver

13. How Does GPS Work?

14. How it works  Satellite circles the Earth and transmits signal  Signal contains time it was sent and its location  All satellites send their signal at the same time  Difference in time to reach receivers is used to determine location

15.  Formula: Distance = Speed x Time  Signal travels at the speed of light – 186,282.3976 miles per second  Speed and Time are known, use to calculate Distance

17. Trilateration  Process of measuring the distance from at least three satellites  Three satellites calculate 2D position (Latitude and Longitude)  Four or more satellites calculate 3D position (Latitude, Longitude, and Altitude)

18. Trilateration

19. One satellite can locate a receiver’s position somewhere on a sphere Two satellites can locate a receiver’s position to a circle representing the intersection of two spheres Three satellites can locate a receiver’s position to one of two points represented by the intersection of three spheres.

20. Latitude  Latitude lines run horizontal  Equator is 0°  North and South Poles are 90°

21. Lines of Latitude

22. Longitude  Also known as meridians, run vertical  The Prime Meridian in Greenwich, England is 0°  Lines range from 0° to 180°  International Date Line is 180°

24. Now for the fun part!

25. Zoom In button Zoom Out button Find button Page Button Power Button Click Stick

26. Satellite PageMap PageNavigation Page

27. Trip PageMain Menu

28. The next lesson we will talk about limitations and accuracy with a GPS receiver.

29. Limitations and Accuracy with GPS

30. Accuracy Problems  Atmosphere Delay  Signal Multipath  Receiver Clock Errors  Number of Satellites Visible  Satellite Geometry and shading  Selective Availability – Turned off

31. WAAS  Developed by the FAA  Wide Area Augmentation System  Increases the accuracy of GPS receivers  Full Operational Capacity on July 10, 2003

32. W ide Area Augmentation System WAAS WAAS Reference Station WAAS Master Station Receiver Corrected Signal

33. Differential Correction  Developed by the Coast Guard  Also known as DGPS  Ten meter or less accuracy  Full Operational Capacity March 15, 1999

34. Differential GPS Correction Signal Stationary Receiver

35. Now what do we do with this information? The next section discusses the uses of GPS

36. Uses of GPS

37. LocatingTrackingNavigatingMappingTiming

38. Using GPS  What are uses you can think of? BoatingFishing HuntingCamping HikingBiking Rafting

39. Using GPS continued  Scouting from land or air, Horseback riding, Hot air ballooning, Aviation, Snowmobiling, Skiing, Search and Rescue, Four wheeling, Emergency Vehicle Tracking, Highway Driving  Geocaching, Surveying, Military, Precision Agriculture

40. Using GPS continued  Survey disaster areas, Map movement of environmental disasters (Oil spills, wild fires, floods, etc)  Mapping fallout shelters, sidewalks, streets, trees, trails, etc.  Measuring the growth or decline of mountains

41.  How does GPS improve these activities? Makes the location more preciseMakes the location more precise User FriendlyUser Friendly Mapping is easierMapping is easier Universal systemUniversal system Fun!Fun!

42. What can you do with GPS?

43. GPS/GIS and 4-H  Potential Projects Youth Favorite PlacesYouth Favorite Places  www.youthfavoriteplaces.org www.youthfavoriteplaces.org GeocachingGeocaching  www.geocaching.com www.geocaching.com National GPS / GIS Integration TeamNational GPS / GIS Integration Team  http://www.4-h.org/ http://www.4-h.org/ The National Map CorpsThe National Map Corps  http://nationalmap.gov/TheNationalMapCorps/ http://nationalmap.gov/TheNationalMapCorps/

44. GPS/GIS and 4-H Community AtlasCommunity Atlas  ESRI Grants  http://www.esri.com/industries/k- 12/atlas/index.html http://www.esri.com/industries/k- 12/atlas/index.html http://www.esri.com/industries/k- 12/atlas/index.html  http://gis.esri.com/industries/k- 12/commatlas/browse.cfm http://gis.esri.com/industries/k- 12/commatlas/browse.cfm http://gis.esri.com/industries/k- 12/commatlas/browse.cfm Environmental Impact TeamEnvironmental Impact Team  Waterwell Mapping Waterwell Mapping Waterwell Mapping The Globe ProjectThe Globe Project  www.globe.gov www.globe.gov

45. GPS/GIS and 4-H  Oklahoma Project Ideas Danger SignsDanger Signs Historic Downtown AreasHistoric Downtown Areas Illegal Dump locationsIllegal Dump locations Health and Wellness benefitsHealth and Wellness benefits Storm SheltersStorm Shelters Nature Trails and/or VegetationNature Trails and/or Vegetation