1. Introduction to the Global Positioning System by Dr. Stephen C. Brown University of Alaska at Fairbanks Mat Su /Copper River District

2. WHAT IS GPS? Satellite based radio positioning system Developed and maintained by the U.S. Department of Defense Made up of three segments: W Space W Control W User or Ground receivers Used for obtaining accurate locations any where on earth

3. GPS Is An Excellent Mapping Tool –Instantly gives: Altitude Speed Longitude and Latitude

4. Space Segment

5. USER SEGMENT LAND SEA AIR NEED Four SV’s.

6. Maintained by the Department of Defense Control Segment

7. How It Works…. Trilateration

12. Increasing Accuracy: Wide Area Augmentation Service (WAAS) 100 m15 m <3m

13. Recognizing Coordinate Systems Format Type Example Coordinate (all are same position) Degrees, Minutes, Seconds (DMS): 29 0 34’ 15” Decimal Minutes (DM): 29 0 34.25’ Decimal Degrees (DD): 29.57080 29 0 34’ 15” is the same as 29 34 15 29 0 34.25’ is the same as 29 34.25

14. Universal Transverse Mercator (UTM) Coordinates A “metric” coordinate system 5V605913.13 E 6707279.66 N 605913.13 meters Easting 6707279.66 meters Northing

15. UTM Zones

16. The Right Datum is Important! GPS data stored in WGS84/NAD83 datum and displaying them with GIS data in NAD27 datum can result in 100's of meters in error!

17. Error Problems in Alaska SV’s are on an southern equatorial plane Mountains often block the sky Extreme cold impact batteries

18. PRACTICAL APPLICATIONS Navigation Sailing, hiking and aviation Collecting and locating way-points Locating Features Stocking locations or stream surveys Endangered or sensitive species locations Locating trails or physical structures GIS Collecting GPS data along with attribute data Mapping and database update Surveying Locating Control Points quickly

23. Garmin GPS Receivers Inexpensive and downloadable Available locally for less than $150 Most GPS receivers similar in operation

25. SV Visibility clear viewobstructed view

27. SkyView Page Satellite status appears while the unit “finds” the satellites Acquisition can take several minutes

32. Waypoints track waypoint 1 2 3 4

33. Creating Waypoints

35. Selecting Waypoints

38. What is Geocaching? Geocaching is a worldwide “scavenger hunt” using GPS to find “caches” of treasure. The only rules are to leave something if you take something and do not disturb the cache

42. www.easygps.com

43. GPS Online Resources www.garmin.com www.trimble.com www.geocaching.com www.earth.google.com

44. Steve Brown: ffscb2@uaf.edu 907-745-3639 Mat-Su/Copper River District University of Alaska Fairbanks Cooperative Extension Service