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GNSS Reference Station Network Applications

– Status and Vision

Herbert LandauTrimble Munich, Germany

January 2011

• GNSS network as reference frame• Positioning with cm-accuracy• Monitoring • Ionospheric research • Meteorology

Multiple use of GNSS Networks

Trimble Multi-Server Software Platform

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GNSS Networking Real-Time Correction Services

• More than 4000 stations operated by Trimble software

• Eliminating/mitigating errors like orbit, ionosphere, troposphere

• Real-time corrections to RTK rovers via GPRS/3G modems

• cm-accurate RTK positioning in a unified coordinate frame

• Better accuracy, reliability, productivity• International standard, e.g. RTCM

Reference Station data streaming to the Control Center

User receiver sends its position to the Control Center via cell phone

Position

Control Center transmits optimized correction stream for each user via cell phone (creating a virtual local

reference station VRS)

Network RTK Applications

• Survey• Machine control• Agriculture• Mapping&GIS

Monitoring in VRS³NetPlate Tectonics

Earthquake in Chile February 27, 2010

Monitoring in VRS³NetEarthquakes

Earthquake in Chile February 27, 2010

Monitoring in VRS³NetEarthquakes

Santiago movement

Feb. 27, 2010, Day 58

Monitoring Example: Subsidence of Oil Platforms

Rate up to decimeters per year

Monitoring Example: Bridge collapse

Update rates up to 10 Hz

GNSS Networks & Meteorology

• Water vapor highly variable quantity• Water vapor for short-term forecasts of

precipitation• Water vapor (62%) biggest component to

contribute to greenhouse effect (carbon dioxide 22%)

• Global increase of precipitable water observed • Computation of Integrated Precipitable Water

Vapor (IPWV) from – network GNSS data– Ground meteorological data

• RMS in IPWV < 1mm

GNSS derived Water Vapor European Network (estimates every 15 seconds)

Radar ImageGNSS derived water vapor

Ionospheric Solar CycleMaximum in 2013/2014

06:00 am UTC 12:00 am UTC 06:00 pm UTC

Ionosphere and GNSSReal-Time Warning Sytem

Summary

• Worldwide GNSS networks (several thousands of stations)

• Benefits for many scientific, state official and commercial applications

• Solutions for server and rovers • New GNSS signals will increase

applicability– GPS L5, GLONASS CDMA, Galileo, QZSS,

Compass, IRNSS

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