1. Will you be… MappingMapping or Navigating?Navigating Which GPS Receiver Do I Need?

2. “Mapping” is any activity or process that produces a graphical representation of a ground feature by means of a point, line or polygon. While mapping you may need to produce attribute data concerning the features that you are mapping. One resulting product from a mapping project is a GIS data layer or theme. If you would like to learn more about attribute feature data collection choose the “Mapping Features” button below, otherwise pick the “Continue” button. Continue Mapping Features

3. Sub-meter5 – 25 m. Post-Processed Differential Autonomous NDGPSWAAS Mapping Real-Time Differential 1 – 5 m. Post-Processed Differential Home Required Accuracy: Process:

4. 1 – 5 m.5 – 25 m. Autonomous NDGPSWAAS Navigation Home Real-Time Differential Required Accuracy: Process:

5. Collect GPS Data Download and Post-Process the GPS Data Post-Processed Differential Corrections 1 – 5 meter accuracy Sub-meter if you collect and process carrier-phase data More Information Back Back to Mapping

6. Autonomous Receiver Operations 5 – 25 meters More Information Back Back to Mapping Back to Navigating

7. Real-time Differential Corrections 1 – 5 meters NDGPS WAAS More Information Back Back to Mapping Back to Navigating

8. Post-Processed Differential Corrections Examples of Receivers: Trimble XR and XRS Series (~ $10,000) Trimble GeoExplorer CE XT (~ $6,000) Garmin Receiver with Rhino™ Data Collection and Post-processing Software (~$1500) Back Back to Mapping Back to Navigating

9. Autonomous Receiver Operations Examples of Receivers: Trimble XR and XRS Series (~ $10,000) Trimble GeoExplorer CE XT (~ $6,000) CSI MiniMax (~ $2500) Garmins (~ $100 - $1000) Magellans (~ $100 - $3000) Back Back to Mapping Back to Navigating

10. Real-time Differential Corrections Examples of Receivers: Trimble XR and XRS Series (~ $10,000) Trimble GeoExplorer CE XT (~ $6,000) CSI MiniMax (~ $2500) Garmins (~ $200 - $1500) Magellans (~ $200 - $3000) Back Back to Mapping Back to Navigating

11. Sub-meter Considerations: Expensive 10 minute (or more) approximate occupation time Used primarily for point positioning Back

12. 1 –5 Meter Accuracy Considerations: Post-processed option is more expensive than real-time Real-time may not be available or practical for operations Back

13. Autonomous ( 6 –25 m.) Considerations: Can be very inexpensive Will not meet most requirements for mapping Back

14. Nationwide Differential GPS Service Considerations: More expensive than WAAS since an additional receiver is required Is usually (but not always) slightly more accurate than WAAS Is not line-of-sight. It can be used in the trees and in terrain that WAAS cannot Back More Information Coast Guard NDGPS Website: http://www.navcen.uscg.gov/dgps/Default.htm

15. Wide Area Augmentation System Considerations: Less expensive than NDGPS because no additional receiver is needed. GPS receiver must be WAAS enabled No wires Limited to line of sight operations to geo-stationary satellite parked over equator Unreliable in many field operating environments Usually less accurate than NDGPS Back More Information Department of Transportation WAAS Website: http://gps.faa.gov/programs/waas/howitworks.htm http://gps.faa.gov/programs/waas/howitworks.htm

16. Mapping Features: There are basically two options for collecting attributes in the field: Trimble equipment with TerraSync or ArcPAD Data collection software such as ESRI’s ArcPAD on a PDA plugged into any GPS receiver. Each has advantages and disadvantages. Pick the “More Information” button for additional info. Back to Mapping Back More Information

17. Trimble Equipment: GeoExplorer XT is relatively small and self-contained Trimble XR and XRS are highly accurate and reliable Pathfinder Office Software is powerful and feature packed Expensive ($6000 - $10,000) Note: If you use ArcPAD and want to do post-processed differential corrections then you must buy “GPS Correct” software (~$500) from Trimble. GeoExplorer XTTrimble XR More Information at Trimble’s website: http://www.trimble.com Back to Mapping Back More Information

18. PDA with Data Collection Software: Flexible solution Wide range of related costs ($250 - $6000) depends on selected hardware and software Can be very powerful and feature packed Back to Mapping Back ERSI’s ArcPAD