Product catalogue
Self-Calibration of wet troposphere delay and clock phase variations for VLBI data analysis
<div>The wet tropospheric component and clock phase variations are the most important factors that limit the accuracy of the geodetic VLBI products. These fast fluctuations can be introduced into the parametric model as a correlated stochastic noise and treated in a special way using the least square collocation method (LSCM). An a-priori covariance function is used to construct the non-diagonal covariance matrix. We have developed a procedure to calculate the wet troposphere delay and the clock offset for each observation epoch. The wet troposphere delays calculated by the LSCM are in perfect agreement with the water vapour radiometer (WVR) data, within the uncertainty of 2-3 mm. This information is then incorporated into the NGS data file and used in the second iteration. As a result, the procedure for analysing the VLBI data becomes simpler and faster, since the remaining observational error is Gaussian, and the matrix of the observational covariance can be treated as diagonal. For the calibrated VLBI data, the simple least squares method (without breaking the 24-hour experiment into small bins) is applied, followed by a reduction in the number of estimated parameters. All VLBI data between 1993 and 2023 were processed with pre-calibrated tropospheric and clock delays. The result was tested with two independent software packages, OCCAM and VieVS, and showed a good efficiency with respect to the traditional approach. The accuracy of the estimates reaches: 1 mm for VLBI site positions, 3 µas for UT1-UTC values, 40 mas for X- and Y-pole components. The formal error of the most observed ICRF reference radio source positions drops to 1-2 µas, and the ”floor” (or ”inflated”) error for the future ICRF realization would also be reduced. This paper shows that the new data analysis procedure produces results which align with the announced VGOS goals for the S/X VLBI data. Finally we report a detection of the negative parallax effect with an amplitude of −15.8(±0.5) µas.
Abstract presented at the 2024 13th General Meeting of the International VLBI Service for Geodesy and Astrometry (IVS), Tsukuba, Japan
Simple
Identification info
- Date (Creation)
- 2024-05-19T12:00:00
- Date (Publication)
- 2024-07-15T02:08:18
- Citation identifier
- Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/149628
- Cited responsible party
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Role Organisation / Individual Name Details Publisher Commonwealth of Australia (Geoscience Australia)
Voice Author Titov, O.
Internal Contact Author Willcocks, S.
Internal Contact Author Krasna, H.
External Contact Author Lopez, Y.
External Contact Author Osetrova, A.
External Contact
- Name
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13th General Meeting of the International VLBI Service for Geodesy and Astrometry (IVS), 4-9 Marche 2024, Tsukuba, Japan
- Purpose
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improvement of fundamental reference frame
- Status
- Completed
- Point of contact
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Role Organisation / Individual Name Details Resource provider Space Division
External Contact Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Titov, O.
Internal Contact
- Spatial representation type
- Topic category
-
- Geoscientific information
Extent
))
- Maintenance and update frequency
- Not planned
Resource format
- Title
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Product data repository: Various Formats
- Protocol
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FILE:DATA-DIRECTORY
- Name of the resource
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Data Store directory containing the digital product files
- Description
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Data Store directory containing one or more files, possibly in a variety of formats, accessible to Geoscience Australia staff only for internal purposes
- Project
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geodesy
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- Keywords
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astrometry
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- Keywords
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data analysis
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- Keywords
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geodesy
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- Keywords
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Very Long Baseline Interferometry (VLBI)
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- theme.ANZRC Fields of Research.rdf
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Earth system sciences
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- Keywords
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Published_External
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Resource constraints
- Title
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Creative Commons Attribution 4.0 International Licence
- Alternate title
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CC-BY
- Edition
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4.0
- Addressee
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Role Organisation / Individual Name Details User Any
- Use constraints
- License
- Use constraints
- Other restrictions
- Other constraints
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(c) Commonwealth of Australia (Geoscience Australia) 2024
Resource constraints
- Title
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Australian Government Security Classification System
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
- Classification system
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Australian Government Security Classification System
- Language
- English
- Character encoding
- UTF8
Distribution Information
- Distributor contact
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Role Organisation / Individual Name Details Distributor Commonwealth of Australia (Geoscience Australia)
Voice facsimile
- OnLine resource
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Link to Conference Page
Link to Conference Page
- Distribution format
-
- OnLine resource
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Link to Short Abstract Volume (85-06 page 41)
Link to Short Abstract Volume (85-06 page 41)
- Distribution format
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- OnLine resource
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Link to Presentation
Link to Presentation
- Distribution format
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- OnLine resource
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Download Extended Abstract (pdf) [1.3 MB]
Download Extended Abstract (pdf) [1.3 MB]
- Distribution format
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pdf
- File decompression technique
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nil
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Resource lineage
- Statement
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<div>Analysis of VLBI observations by OCCAM software</div>
Metadata constraints
- Title
-
Australian Government Security Classification System
- Edition date
- 2018-11-01T00:00:00
- Classification
- Unclassified
Metadata
- Metadata identifier
-
urn:uuid/78fef9c8-4ad2-4a77-a4b1-092c8b098318
- Title
-
GeoNetwork UUID
- Language
- English
- Character encoding
- UTF8
- Contact
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Role Organisation / Individual Name Details Point of contact Commonwealth of Australia (Geoscience Australia)
Voice Point of contact Titov, O.
Internal Contact
Type of resource
- Resource scope
- Document
- Name
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Journal Article / Conference Paper
Alternative metadata reference
- Title
-
Geoscience Australia - short identifier for metadata record with
uuid
- Citation identifier
- eCatId/149628
- Date info (Creation)
- 2024-07-15T01:20:25
- Date info (Revision)
- 2024-07-15T01:20:25
Metadata standard
- Title
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AU/NZS ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-1:2014
Metadata standard
- Title
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ISO 19115-3
- Title
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Geoscience Australia Community Metadata Profile of ISO 19115-1:2014
- Edition
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Version 2.0, September 2018
- Citation identifier
- http://pid.geoscience.gov.au/dataset/ga/122551