1. MODULE
1
GNSS (GPS) Workflow and
Integration into GIS
Karyn Nolan

2. Top 3 Questions
 What is the accuracy of the equipment?
 How do I have a picture as an attribute?
 Why is my data in the ocean?
 ….other tips along the way

3. Differential Corrections
Real Time Accuracy
 Autonomous
– 10 m with uncorrected GPS
 Satellite Based Augmentation System (SBAS) – 1-5 m
– WAAS - US
– EGNOS - Europe
– MSAS – Japan
– GAGAN - India

4. VRS - Difference in Accuracy
between traditional RTK and VRS

5. Future Trend
Real Time Accuracy
 VRS subscription or Single Base broadcast
– cell phone or radio
– http://www.trimble.com/infrastructure/services.aspx
100cm
VBS/WAAS/EGNOS
15cm
XP/G2
10cm
HP
4cm
CenterPoint
RTX
2cm
RTK/VRS
0cm

6. Trimble VRS Now Network
Europe: Czech Republic, Estonia,
Great Britain, Germany,
Netherlands, Belgium, Luxembourg
& Ireland
Estonia
Ireland
Great-
Netherlands
Britain
Germany
Belgium Czech
U.S.: Alabama, Colorado, Florida, Illinois, Lux
Iowa, Indiana, Kentucky, Mississippi and
Nebraska
Madrid

7. Differential Corrections – Post Process
 Post Processed Accuracy (PPA)
 Corrections applied in office software
– CORS
– Achieve Specifications of Equipment!!

8. Global Navigation Satellite System
What is the Global Navigation Satellite System, GNSS?
 GPS – US Global Positioning System
 GLONASS – Russian GLObal NAvigation Satellite System
 Galileo – European Union (currently non-functional)

17. Questions
Pacific GPS, LLC
(808) 538-7477
www.pacificgps.com
info@pacificgps.com