High Accuracy GPS Mapping and VRS Lanny Schnipper Seiler Instrument 2008 IGIC Conference Indianapolis, IN

VRS in Action No base setup MWRTK VRS in Indiana get to the job dial in Check start working MWRTK VRS in Indiana save time save money

Overview Review GPS Discuss use of Virtual Reference Stations (VRS) Obtaining highly accurate GIS/GPS positions Continuously Operating Reference Stations (CORS) Real-Time differential results

What is VRS? GPSNet, DGPSNet, RTKNet Links a network of reference stations Provides quality control of incoming data Logs files for post-processing Network modeling of systematic errors Real time broadcast of true network DGPS and RTK solutions

VRS Data Flow Reference stations data streams back to the server through LAN, Internet, or radio links

VRS Data Flow User’s receiver sends an NMEA string back to server using cellular modem. Virtual Reference Station position is established. VRS NMEA—GGA

VRS Data Flow Server uses VRS position to create corrected observables and broadcasts them to the user end. RTCM or CMR+ VRS

Why use VRS? Eliminates the need for Users to establish DGPS base/reference station(s) More reference stations = shorter vectors/ baselines Shorter baselines = less atmospheric errors Network atmospheric modeling Extended operating range with improved accuracy

Why use VRS? VRS provides integrity monitoring All users in common, established coordinate frame Eliminates the dependency on single base/reference station Graceful degradation should a reference station fail Uses established communications Productivity lost through having to establish base station – locate co-ordinates, set up comms and power, provide security (additional person). Radio frequency and range issues. Battery charging.

Indiana MWRTK 26 Stations …and growing!

Indiana MWRTK www.mwrtk.net

Real Time in TerraSync/ArcPad External correction source Data radio Beacon-on-a-Belt (BoB™) receiver GeoBeacon SBAS (WAAS) TerraSync Version 2.30 (2/03) added VRS Network VRS Single base GPSCorrect Version 1.1 (4/05)

Support VRS corrections GeoExplorer CE series with GPS firmware version 1.03: GeoXT GeoXM GeoXH GPS Pathfinder with firmware version 1.52 or later: GPS Pathfinder Power GPS Pathfinder Pro XRS GPS Pathfinder Pro XR GPS Pathfinder ProXH GPS Pathfinder ProXT

Connecting to VRS Internet connection to the VRS server GPRS-capable cellphone WiFi Hotspot Serial cable connection Data radio

Outside TerraSync Start  Settings  Connections Make connection to your Phone or other device Test Internet Explorer to insure connection was successful

Inside TerraSync Start TerraSync Select Setup section Set Real-time Settings Choice 1 field select External Source. Configure the external source From the Type field, select VRS or select the Single Base option Connection Method field, select Internet Address field, enter the IP address or URL of the VRS server. IP Address: 64.123.250.18 for MWRTK IP Port: 2101 for MWRTK

Accuracy Submeter with a GeoXT/XH Usually subfoot We have even seen less than 6 inches! No post-processing required

Subscription VRS is a paid subscription Seiler provides Logon and password MWRTK.NET Single Day - $20 per day, 3-day minimum per month maximum monthly charge $200 (Billed monthly) Single Month- $150 (Billed monthly and payable in advance) Single Quarter- $375 ($125 per month) (Billed quarterly and payable in advance) One Year- $1,200 (Billed $225.00 per quarter and payable in advance)

Questions?