WP3.1: GNSS Campaigns and Research DOP - ife.uni-hannover.de · Deformationsüberwachung mit...
Transcript of WP3.1: GNSS Campaigns and Research DOP - ife.uni-hannover.de · Deformationsüberwachung mit...
The Joint Research Project SIMULTANWP3.1: GNSS Campaigns and ResearchTobias Kersten and Steffen Schön
Institut für Erdmessung | Leibniz Universität Hannover | {kersten, schoen}@ife.uni-hannover.de
Urban GNSS Sites and Campaign Design
(a) SL03 (b) GRAV12 (c) GGP1
(d) HHDE (e) HH01 (f) HH09
Figure 1: Co-located urban GNSS sites as part of geo-monitoring networks to control and observe subsidence pro-cesses, (a-c) Bad Frankenhausen (Thuringia), (d-f) Hamburg
Groß-Flottbek.
SIMULTAN-ProjectI Sinkhole Instability, MULTiscale monitoring and
ANalysis: gain a deeper understanding of thecomplex processes, interactions andcharacteristics of the underground and thesurface interaction in urban environments,[Kersten et al., 2017].
GNSS-Campaign Design in SIMULTANI Multi-GNSS equipment (Leica
GRX1200+GNSS, Novatel 703GGG, LeicaAR25.R3) with height adaptor FG ANA 100B forprecise height determination.
I Four hour sessions, at least 3 independentrepetitions per site.
I Data recording (1 Hz) at co-located sites(GNSS, levelling, gravimetry).
I Star-like GNSS monitoring network, fixed inlocal reference stations.
Urban GNSS SitesI Urban infrastructure yields to variable and high
multipath as well as challenging satellitegeometry at each co-located site.
I Short baselines of approx. 700-1800 m.
Hamburg - Network
I HHDE: Local reference station at DESY(Deutsches Elektronen-Synchrotron), stabilitycheck by SAPOS R© stations (Lower Saxony)Buchholz (0680), Stade2 (1662), Lüneburg(0660).
I HH01: Co-located site in a park with severaltrees which reduces satellite visibility at lowelevations.
I HH05: Site located in proposed stableenvironment, northern part, close to DESY. Usedto monitor subsidence in Wobbe-See(HH02-HH04) and the old storage basin (HH08).
I HH03: Co-located site to monitor subsidence;challenging satellite visibility, cf Fig. 3.
2017, IfE-LUH Image: Ortho-photo Hamburg Groß-Flottbek, © BKG 2016, projection: UTM Zone 32N
593550m
593600m
593650m
593700m
Nort
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557000m 557500m 558000m 558500m 559000m
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Hamburg Groß-Flottbek
old storage basin
Flottbek Markt
Wobbe-See
HH09
HH05
HHDE
HH01 HH08
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NivP78
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RF5303
UF3093
HH02HH04
HH03
STD2�(1662)
BHLZ�(0680)
LNBG�(0660)
Hamburg Flottbek(Hamburg, Germany)
Legend
SAPOS-NI GNSS station
Local GNSS reference
Leveling reference
GNSS only
Levling only
GNSS & Leveling
Leveling & Gravimetry
GNSS & Leveling & Gravimetry
areas of subsidence
Map: Ortho-photo, © BKG 2016
Horizontal datum: ETRS89
Vertical datum: DHHN2016
Projection: UTM, zone 32N
Figure 2: Combined geophysical network in Hamburg, Groß-Flottbek.
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Figure 3: Comparison of several DOP-Values (dilution of precision) and overall satellite visibility as quality indicators for characteristicsites of he monitoring network for the local Reference HHDE (a) and a site in the Wobbe-See subsidence area HH03 (b).
Hamburg - Details
Figure 4: Temporal variation for specific height difference in the vicinity of Wobbe-See (HH03) by leveling (ref. to Niv.P78) and byGNSS (ref. to HH05). Both points are located in the north of the subsidence area.
I Subsidence processes observed although the scale of drift is very small (1.5-2 mm).
I Independent methods (leveling and GNSS) agree very well and show drift in the areas of interest.
I Results evaluated in cooperation with AP/WP 3.2 and 3.3, gravity changes between sites indicatefurthermore mass transport (separation from seasonal signals), [Weise et al., 2017a, Weise et al., 2018].
Hamburg - GNSS Repeatability
FindingsI Generally, repeatability with magnitudes of 2 mm
achieved, higher values caused by vegetationand frequent traffic at sites.
I Optimal location for co-location sites of interest(leveling, gravimetry) not at any time feasible, cf.Fig. 3, [Icking et al., 2016].
I Magnitudes of RMS generally at 0.3-0.4 mm and0.2-0.3 mm (optimal sites), respectively (cf.Fig. 5). HH03 HH05
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October 2015 (reference)April 2016 (1st Epoch)September 2016 (2nd Epoch)April 2017 (3rd Epoch)September 2017 (4th Epoch)
Legend
Figure 5: Characteristic repeatability of co-located sites to moni-tor subsidence in different scales (time, depth, spartial).
Bad Frankenhausen - Network
GRAV01
GRAV02
GRAV06
GRAV10
GRAV11
GRAV12
GRAV3
GRAV4 GRAV5 GRAV7
GRAV8
GRAV9
SL03
0 km 0.1 km 0.2 km
map scale
© GeoBasis−DE / BKG (2016)
S o u t h E a s t K y f f h ä u s e r
GRAV02SL03GGP1
’Rathaus’
AP2
AP4
100
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400Altitude (m)
11°04' 11°06' 11°08'
51°20'
51°22'
51°24'
Bad Frankenhausen (Thuringia, Germany)
Legend
GNSS / Levelling / Gravimetry Levelling / Gravimetry GNSS only GNSS baselines Levelling only (between AP2 and AP4)
0 1 2
km
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(a) GNSS network Bad Frankenhausen
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SNV 19reference SVN 12EL1C: 1,2cmEL5Q: 2,3cmEL7Q: 2,2cmEL8Q: 2,1cm
Legend
(b) SL-12: DD and elevation versus GPS Time
Figure 6: Analysis of Galileo GNSS sites, (a) network with indicated baseline, (b) double difference residuals for four hour sessioncaptured at GRAV12 (cf. Fig. 1b).
I SL03: Local reference station (stability check by SAPOS R© stations Erfurt (0209), Buttstädt (0221),Sondershausen (0200), Mühlhausen (0214)).
I GRAV12: Co-located point in close vicinity to a concrete wall (located in the north of the GNSS site),challenging obstruction geometry present.
I Baseline SL03-GRAV12 (SL-12): 190 m, significant impact of multipath detectable.
I Multipath signatures detectable (sinusoidal) with frequencies of ≈20 minutes that lead to amplitudes inGalileo DDs (E5a, E5b and AltBOC E5a+b) although low noise is present. Highest noise on Galileo E1signal detected, [Ruwisch et al., 2016].
Conclusions and Further Steps
I Study of Galileo observations in challenging, urban environments by [Ruwisch et al., 2016].
I Challenging satellite geometry improved by applying adaptive dynamic elevation masks (dynMsk)studied by [Icking et al., 2016].
I Campaigns finished and processing of epoch comparisons ongoing; solutions published frequently.
I Data provided through WebDAV server for both projects (HHX and BFH) for dedicated WP partners.
Ongoing and further stepsI Development and evaluation of integrated model for leveling and gravimetric data sets,
[Kersten et al., 2017, Weise et al., 2017b].
I Quantification and separation of superimposed signals as e.g. hydrological, atmospheric, seasonalvariations and tidal effects.
I Studies and application of GNSS low-cost reference stations in combination with urban infrastructure asstreet furniture like, e.g. streetlamps etc., [Kröger et al., 2017] to gain consistent and longer time series.
Acknowledgement & Funding
Acknowledgement The authors thank the TLVerm Thuringia, the Glückauf Vermessung GmbH Sondershausen, the MEA2 Groupof the German Electron Synchrotron (DESY) and the city of Bad Frankenhausen for their kind and friendly cooperation.Additional FG ANA 100B GNSS height adaptors and corresponding accessories were provided by the LGLN (LowerSaxony). The Center of Orbit Determination in Europe (CODE) is grateful acknowledged for providing freely high preciseorbits and corresponding products.
Funding The work in the project of SIMULTAN is funded under the grant 03G0843D by the Federal Ministry of Education andResearch, based on a resolution by the German Bundestag.
References
Icking, L., Kersten, T., und Schön, S. (2016). Dynamische und adaptive Elevationsmasken zur Optimierung von GNSS-Netzen. InGeodätische Woche 2016, 11.-13. Oktober, Hamburg.
Kersten, T., Kobe, M., Timmen, L., Schön, S., und Vogel, D. (2017). Geodetic Monitoring of Subrosion-Induced SubsidenceProcesses in Urban Areas - Concept and Status Report. Journal of Applied Geodesy, 11(1):21–30. DOI: 10.1515/jag-2016-0029.
Kröger, J., Kersten, T., und Schön, S. (2017). GPS/GNSS Low Cost Permanent-Stationen für urbane Monitoringnetze. InGeodätische Woche 2016, 26.-28. September, Berlin.
Ruwisch, F., Kersten, T., und Schön, S. (2016). GNSS-Doppeldifferenzanalyse für urbane Monitoring-Ansätze. In GeodätischeWoche 2016, 11.-13. Oktober, Hamburg.
Weise, A., Gabriel, G., Kersten, T., Schön, S., Timmen, L., und Vogel, D. (2017a). Deformationsüberwachung mit Gravimetrie?Ein Experiment im Erdfallgebiet in Hamburg-Flottbek. In Jahrestagung der Deutschen Geophysikalischen Gesellschaft, March27-30, Potsdam, Germany.
Weise, A., Kersten, T., Schön, S., Timmen, L., und Vogel, D. (2017b). Deformationsüberwachung mit Gravimetrie? EinExperiment im Erdfallgebiet in Hamburg-Flottbek. In Proceedings of 77. Jahrestagung der Deutschen GeophysikalischenGesellschaft, March 27.-30., Potsdam, Germany.
Weise, A., Kersten, T., Timmen, L., Gabriel, G., Schön, S., und Vogel, D. (2018). Ein integrativer geodätisch-gravimetrischerAnsatz zur Erkundung von Subrosion im Erdfallgebiet Hamburg Flottbek – Oberfächendeformation und Massentransfer.Allgmeeine Vermessungsnachrichten - Sonderheft Geomonitoring, Seiten 1–16. (accepted).
(Projekträger Jülich :: Status-Seminar Dresden, Grant-ID: 03G0843D) Created with LATEX