<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The complex demodulation (CD) algorithm is an efficient tool for extracting the diurnal and subdiurnal components of Earth rotation from the routine VLBI observations (<xref ref-type="bibr" rid="j_arsa-2016-0012_ref_004_w2aab2b8b8b1b7b1ab1ab4Aa">Brzeziński, 2012</xref>). This algorithm was implemented by <xref ref-type="bibr" rid="j_arsa-2016-0012_ref_002_w2aab2b8b8b1b7b1ab1ab2Aa">Böhm et al (2012b)</xref> into a dedicated version of the VLBI analysis software VieVs. The authors processed around 3700 geodetic 24-hour observing sessions in 1984.0-2010.5 and estimated simultaneously the time series of the long period components as well as diurnal, semidiurnal, terdiurnal and quarterdiurnal components of polar motion (PM) and universal time UT1. This paper describes the tests of the CD algorithm by checking consistency of the low frequency components of PM and UT1 estimated by VieVS CD and those from the IERS and IVS combined solutions. Moreover, the retrograde diurnal component of PM demodulated from VLBI observations has been compared to the celestial pole offsets series included in the IERS and IVS solutions. We found for all three components a good agreement of the results based on the CD approach and those based on the standard parameterization recommended by the IERS Conventions (<xref ref-type="bibr" rid="j_arsa-2016-0012_ref_018_w2aab2b8b8b1b7b1ab1ac18Aa">IERS, 2010</xref>) and applied by the IERS and IVS. We conclude that an application of the CD parameterization in VLBI data analysis does not change those components of EOP which are included in the standard adjustment, while enabling simultaneous estimation of the high frequency components from the routine VLBI observations. Moreover, we deem that the CD algorithm can also be implemented in analysis of other space geodetic observations, like GNSS or SLR, enabling retrieval of subdiurnal signals in EOP from the past data.</p></abstract>

The complex demodulation (CD) algorithm is an efficient tool for extracting the diurnal and subdiurnal components of Earth rotation from the routine VLBI observations (Brzeziński, 2012). This algorithm was implemented by Böhm et al (2012b) into a dedicated version of the VLBI analysis software VieVs. The authors processed around 3700 geodetic 24-hour observing sessions in 1984.0-2010.5 and estimated simultaneously the time series of the long period components as well as diurnal, semidiurnal, terdiurnal and quarterdiurnal components of polar motion (PM) and universal time UT1. This paper describes the tests of the CD algorithm by checking consistency of the low frequency components of PM and UT1 estimated by VieVS CD and those from the IERS and IVS combined solutions. Moreover, the retrograde diurnal component of PM demodulated from VLBI observations has been compared to the celestial pole offsets series included in the IERS and IVS solutions. We found for all three components a good agreement of the results based on the CD approach and those based on the standard parameterization recommended by the IERS Conventions (IERS, 2010) and applied by the IERS and IVS. We conclude that an application of the CD parameterization in VLBI data analysis does not change those components of EOP which are included in the standard adjustment, while enabling simultaneous estimation of the high frequency components from the routine VLBI observations. Moreover, we deem that the CD algorithm can also be implemented in analysis of other space geodetic observations, like GNSS or SLR, enabling retrieval of subdiurnal signals in EOP from the past data.

Complex Demodulation in Monitoring Earth Rotation by VLBI: Testing the Algorithm by Analysis of Long Periodic EOP Components

Space Research Centre, Polish Academy of Sciences, Warsaw,

Inst. of Geodesy and Geodetic Astronomy, Warsaw University of Technology, Warsaw,

Department of Geodesy and Geoinformation, Vienna University of Technology, Vienna,

Artificial Satellites

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The complex demodulation (CD) algorithm is an efficient tool for extracting the diurnal and subdiurnal components of Earth rotation from the routine VLBI...

Complex Demodulation in Monitoring Earth Rotation by VLBI: Testing the Algorithm by Analysis of Long Periodic EOP Components

Published Online: Dec 23, 2016

Page range: 135 - 147

Received: Jun 15, 2016

Accepted: Nov 04, 2016

DOI: https://doi.org/10.1515/arsa-2016-0012

Keywords
Earth Orientation Parameters, Earth Rotation, Very Long Baseline Interferometry, Complex Demodulation

© 2016 Artificial Satellites

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Complex Demodulation in Monitoring Earth Rotation by VLBI: Testing the Algorithm by Analysis of Long Periodic EOP Components

Published Online: Dec 23, 2016

Page range: 135 - 147

Received: Jun 15, 2016

Accepted: Nov 04, 2016

DOI: https://doi.org/10.1515/arsa-2016-0012

KeywordsEarth Orientation Parameters, Earth Rotation, Very Long Baseline Interferometry, Complex Demodulation

© 2016 Artificial Satellites

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Earth Orientation Parameters, Earth Rotation, Very Long Baseline Interferometry, Complex Demodulation