1. Real - Time Deformation Monitoring of GPS Networks
Leoš Mervart, Zdeněk Lukeš,
Christian Rocken, James Johnson

2. Real-Time GPS Applications
Technique
Accuracy
Observables
SPP
0.5 m – 30 m
code
DGPS
< 1.0 m
code + (phase)
RTK
1 – 3 cm (H)
3 – 6 cm (V)
phase + (code)
RDRTK
Reduced-Dynamic RTK (RDRTK)
assumption concerning the receiver motion
increased reliability of ambiguity resolution
longer baselines

3. Real-Time NETwork Software (RTNET)
Participants:
GPS Solutions Inc., Boulder, Colorado
Nippon GPS Solutions Corporation, Tokyo, Japan
Institute of Geodesy, TU Prague

4. RTNET – Menu System

5. RTNET Features
designed for real-time applications (running in post-processing mode possible)
sophisticated algorithms for adjustment (stable filter) and ambiguity resolution
statistically correct network adjustment (full variance-covariance matrix)
written in C++ using object-oriented programming style
Server Mode:
deformation monitoring
real-time estimation of the troposphere
generation of DGPS corrections, FKP corrections, and VRS data
Client Mode:
PPP
DGPS
RTK on long baselines

6. Colorado Test Network
GPS Solutions Inc.
Boulder, Colorado

7. DGPS Application
MS750
StarFire
NGS
(RTNET)

8. GEONET

9. Tokachi-Oki Earthquake

10. Tokachi-Oki Earthquake

11. Tokachi-Oki Earthquake

12. Conclusions
The newly developed software RTNET is capable of resolving the wide-lane and narrow-lane ambiguities and to compute the receiver positions in RTK mode on ~100 km - baselines providing that the amplitude of motion does not exceed several decimeters. We called this application “reduced-dynamic RTK”.
-  We used the new software for the processing of data stemming from the Japanese permanent GPS network GEONET. We processed the data collected during the Tokashi-Oki Earthquake in a mode that strictly corresponded to the real-time processing.
-  The “reduced-dynamic RTK” clearly results show the oscillations of the GPS stations during the earthquake. The amplitudes of these short-periodic oscillations reach several decimeters and depend on the distance between the GPS receiver and the earthquake epicenter. The arrival of seismic waves at GPS stations is clearly visible. It demonstrates the feasibility of real-time GPS seismology.
- RTNET is routinely used at GSI for real-time monitoring of (part of) GEONET