Michiel Otten's research while affiliated with European Space Imaging and other places

Publications (43)

Article
For the realization of the 2020 International Terrestrial Reference Frame (ITRF2020), the International DORIS Service delivered to the International Earth Rotation and Reference Systems Service (IERS) a set of 1456 weekly solution files from 1993.0 to 2021.0 including station coordinates and Earth orientation parameters (EOPs). The data come from f...
Article
Full-text available
In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and mo...
Article
Full-text available
In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and mo...
Presentation
The Sentinel-1,-2, and -3 mission are part of the European Copernicus Programme. The low Earth orbiting satellites are designed for specific Earth observation applications, e.g., InSAR, optical imaging, and radar altimetry. The satellites are all equipped with geodetic-grade GPS receivers allowing for precise orbit determination on the few cm level...
Article
Sentinel-1A is a 2-ton spacecraft of the Copernicus Earth observation program operated by ESA's Space Operations Centre in Darmstadt, Germany. Sentinel-1A and its sister spacecraft Sentinel-1B operate in a sun-synchronous orbit at about 700 km altitude. On 2016/08/23 17:07:37 UTC, Sentinel-1A suffered from an anomaly resulting in a sudden permanent...
Presentation
The switch from the ITRF2008 to the ITRF2014, and the related changes in the IGS GPS satellite antenna calibrations, causes significant changes in the time series of the Sentinel satellite orbits. Consequently the full Sentinel time series has to be reprocessed with new GPS orbit and clocks following the latest IERS, ITRF, and IGS standards. In the...
Article
Twelve years (1991-2003) of ERS-1 and ERS-2 altimetry data have been reprocessed within the European Space Agency (ESA) reprocessing altimeter products for ERS (REAPER) project using an updated, modern set of algorithms and auxiliary models. The reprocessed data set (identified as RP01) has been cross-calibrated against the reprocessed ENVISAT V2.1...
Article
Full-text available
Sentinel-1A is the first satellite of the European Copernicus programme. Equipped with a Synthetic Aperture Radar (SAR) instrument the satellite was launched on April 3, 2014. Operational since October 2014 the satellite delivers valuable data for more than two years. The orbit accuracy requirements are given as 5 cm in 3D. In order to fulfill this...
Poster
The Copernicus POD Service is part of the Copernicus Payload Data Ground Segment of Sentinel-1, -2, and -3 missions. A GMV-led consortium is operating the CPODS being in charge of generating precise orbital products and auxiliary data files for all three missions. The CPODS is based on NAPEOS. The third satellite of the Copernicus programme, Sentin...
Article
In preparation of the 2014 realization of the International Terrestrial Reference Frame (ITRF2014), the International DORIS Service delivered to the International Earth Rotation and Reference Systems Service a set of 1140 weekly solution files including station coordinates and Earth orientation parameters, covering the time period from 1993.0 to 20...
Conference Paper
The Copernicus POD (Precise Orbit Determination) Service is part of the Copernicus PDGS (Payload Data Ground Segment) of the Sentinel missions. A GMV-led consortium is operating the Copernicus POD Service being in charge of generating precise orbital products and auxiliary data files for their use as part of the processing chains of the respective...
Poster
The Copernicus POD (Precise Orbit Determination) Service (CPODS) is part of the Copernicus Payload Data Ground Segment of the Sentinel-1, -2, and -3 missions. A GMV-led consortium is operating the CPODS being in charge of generating precise orbital products and auxiliary data files for all three missions. The CPODS is based on NAPEOS (Navigation Pa...
Chapter
While accuracy of tracking station coordinates is of key importance for Precise Orbit Determination (POD) for altimeter satellites, reliability and operationality are also of great concern. In particular, while recent ITRF realizations should be the most accurate at the time of their computation, they cannot be directly used by the POD groups for o...
Article
An estimated orbit error budget for the Jason-1 and Jason-2 GDR-D solutions is constructed, using several measures of orbit error. The focus is on the long-term stability of the orbit time series for mean sea level applications on a regional scale. We discuss various issues related to the assessment of radial orbit error trends; in particular this...
Chapter
The International DORIS Service (IDS) was created in 2003 under the umbrella of the International Association of Geodesy (IAG) to foster scientific research related to the French DORIS tracking system and to deliver scientific products, mostly related to the International Earth rotation and Reference systems Service (IERS). We first present some ge...
Conference Paper
Full-text available
ESA's first Remote Sensing Satellite: ERS-1 was launched on July 17, 1991 and operated until June 1996, completing one year of parallel operation (Tandem Mission) with ERS-2. Launched in April 1995, ERS-2 has operated for over 14 years with all instrumentation still working well despite the loss of the on-board tape recorders and the transition to...
Conference Paper
Full-text available
The REAPER reprocessing activity has produced a homogeneous, improved ERS altimetry dataset, processed with a uniform set of algorithms and models, and cross-calibrated with ENVISAT. Many improvements have been made to the L1, L2 and Calibration processing of the ERS data. These improvements have largely derived from the processing developed for EN...
Article
Analysis of DORIS stations positions time series from IDS combined solution over time period 2000-2012 has revealed discontinuities linked not with geophysical phenomenon, but correlated with beacons frequency shifts. This result was the consequence of assuming the nominal frequency in the measurement model, and not accounting for beacon frequency...
Conference Paper
Full-text available
ESA's first Remote Sensing Satellite: ERS-1 was launched on July 17, 1991 and operated until June 1996, completing one year of parallel operation (Tandem Mission) with ERS-2. Launched in April 1995, ERS-2 has operated for over 16 years with all instrumentation still working well despite the loss of the on-board tape recorders and the transition to...
Article
Improved orbit solutions of the European Remote Sensing Satellites ERS-1 and ERS-2 have been computed in the ITRF2005 terrestrial reference frame using the recent models based mainly on IERS Conventions 2003. These solutions cover the periods 3 August 1991 to 8 July 1996 for ERS-1, and 3 May 1995 to 4 July 2003 for ERS-2. For each satellite, the fi...
Article
Over the recent years the Navigation Package for Earth Orbiting Satellites, NAPEOS, has evolved to a great tool for satellite geodesy. It is developed and maintained at the European Space Operations Centre (ESOC) of the European Space Agency (ESA) NAPEOS is capable of processing data from all GNSS systems, all DORIS, and all SLR observations. And,...
Article
For the ITRF2008 call for participation ESOC reprocessed the historic data from the IDS, IGS, and ILRS. Our three solutions were computed with one and the same software package NAPEOS, running on the same machine and using, as far as possible, identical settings. Any systematic differences between the technique dependent reference frame solutions m...
Article
For the preparation of ITRF2008, the IDS processed data from 1993 to 2008, including data from TOPEX/Poseidon, the SPOT satellites and Envisat in the weekly solutions. Since the development of ITRF2008, the IDS has been engaged in a number of efforts to try and improve the reference frame solutions. These efforts include (i) assessing the contribut...
Article
Full-text available
For the preparation of ITRF2008, the IDS processed data from 1993 to 2008, including data from TOPEX/Poseidon, the SPOT satellites and Envisat in the weekly solutions. Since the development of ITRF2008, the IDS has been engaged in a number of efforts to try and improve the reference frame solutions. These efforts include assessing the contribution...
Article
Driven by the GMES (Global Monitoring for Environment and Security) and GGOS (Global Geodetic Observing System) initiatives the user community has a strong demand for high-quality altimetry products. In order to derive such high-quality altimetry products, precise orbits for the altimetry satellites are a necessity. With the launch of the TOPEX/Pos...
Conference Paper
Full-text available
New precise orbits of the European Remote Sensing Satellites ERS-1 and ERS-2 have been computed at three institutes (DEOS, ESOC and GFZ) using three different softwares for satellite precise orbit determination (GEODYN, NAPEOS and EPOS-OC) and two different altimetry databases: the Radar Altimeter Database System (RADS) developed at DEOS and suppor...
Article
This paper gives an overview of the DORIS related activities at the Navigation Support Office of the European Space Operations Centre. The DORIS activities were started in 2002 because of the launch of the Envisat satellite where ESOC is responsible for the validation of the Envisat Precise Orbits and a brief overview of the key Envisat activities...
Article
DORIS is one of the four space-geodetic techniques participating in the Global Geodetic Observing System (GGOS), particularly to maintain and disseminate the Terrestrial Reference Frame as determined by International Earth rotation and Reference frame Service (IERS). A few years ago, under the umbrella of the International Association of Geodesy, a...
Article
Terrestrial reference frames are realized by sets of station coordinates that are estimated over a longer period of time using a combination of different space geodesy techniques. However, in the precise orbit determination (POD) of LEO satellites using GPS, reference stations on the ground are not directly used to estimate the orbit of the LEO sat...
Conference Paper
ERS-1 is the first ESA Remote Sensing Satellite, launched on July 17, 1991. It was active until June 1996, completing one year of parallel operation (Tandem Mission) with ERS-2, which is currently still operational. ERS-2 was launched on April 21, 1995 and placed in a 35 days repeat orbit. It was joined by Envisat in March 2002 to guarantee the con...
Article
During 2008 and 2009 ESOC has reprocessed the historic data from the IDS, IGS, and ILRS! Our 3 solution were computed with one and the same software running on the same machine and using, as far as possible, identical settings, a unique achievement. Any systematic differences between the technique dependent reference frame solutions must therefore...
Article
The International DORIS Service (IDS), in operation since 2003, submitted three sets of solutions to ITRF2005 from the IGN/JPL, LEGOS/CLS, and INASAN analysis centers, but no DORIS technique combination. Since that time new analysis centers have become operational including the Geodetic Observatory Pecny (GOP), the European Space Operations Center...
Article
The navigation office of the European Space Operations Centre (ESOC) is engaged in various activities using observations of the Galileo test satellite, GlOVE-A (Galileo In-Orbit Validation Element-A), recorded at the Galileo Experimental Sensor Stations (GESS). The two methods are different due to different tracking networks and the different sensi...
Article
The ITRF2005 solution constituted a significant improvement over all earlier ITRF solutions. Nevertheless significant issues surfaced when the different services, IDS, IGS, ILRS and IVS, started to use the ITRF2005. The most noticeable issue being the scale difference between the SLR and VLBI solution, leading to a special "rescaled" version of the...
Article
The International DORIS Service (IDS), in operation since 2003, submitted three sets of solutions to ITRF2005 from the IGN/JPL, LEGOS/CLS, and INASAN analysis centers, but no DORIS technique combination. Since that time new analysis centers, have become operational, including the Geodetic Observatory Pecny (GOP), and the European Space Operations C...
Article
Full-text available
This paper gives an overview of the processing and reprocessing activities at the European Space Operations Centre (ESOC) of the European Space Agency (ESA). Within ESOC the navigation support office (OPS-GN) is since many years an analysis centre of the International GNSS Service (IGS). Enabled by enhancements of the Napeos software package the OP...
Article
Evaluation of GIOVE satellites' on-board atomic clocks, antenna infrastructure, and signal properties is supported by satellite laser ranging, which provides instantaneous range measurements of millimeter-level precision that can be compiled to provide accurate orbits.
Article
The Navigation Office at ESOC has been closely involved in all aspects of the Precise Orbit Determination (POD) of Envisat throughout the mission lifetime. These activities started shortly after launch through membership of the Orbit Validation Team (OVT). During this time ESOC was involved in both calibration and validation of the DORIS doppler da...
Article
As a principal investigator for the Envisat RA-2 Altimeter the Navigation Office at ESOC has been actively involved in the Calibration and Validation phase of the Altimeter. The activities performed during the Cal/Val phase of the Altimeter consisted of estimation of range and time bias (absolute and relative to ERS-2), validation of the geophysica...
Article
In its position as IGS analysis centre, the ESOC navigation Office has extensive expertise in the processing of GPS data for precise orbit determination purposes. On-going developments in this area include the gradual implementation of real-time processing, and the possible incorporation of GPS data from low Earth orbiting satellites in IGS product...

Citations

... Satellite altimeters provide the main source of observation data to inform sea surface dynamics on a regional and global scale [9,1]. As illustrated in Fig.1, the associated daily sampling at sea surface on a global scale remains very scarce for current nadir altimeter constellations. ...
... Radar altimetry data from ERS-2 (1995ERS-2 ( -2003, ENVISAT (2002ENVISAT ( -2010, SARAL (2013-2016) and SENTINEL-3A and B (since 2016), acquired on the nominal orbit of these missions, were used. Parameters commonly used for estimating the height over land surfaces were selected (e.g., [11]). They were made available by the Centre de Topographie des Océans et de l'Hydrosphère (CTOH): http://ctoh.legos.obs-mip.fr. ...
... For ERS-1 and ERS-2, we used version RP01 of the Level 2 (L2) Geophysical Data Record (GDR) product from the REAPER (REprocessing of Altimeter Products for ERS) project, which has been reprocessed to align both the ERS and Envisat datasets (Brockley et al., 2017). For Envisat, we downloaded the latest L2 GDR product, version 3.0, from ESA, which is better than the previous version (version 2.1) in terms of coverage and performance at crossovers. ...
... Thus, a trade-off has to be made between instrumentation and methodology dedicated to precise orbit and baseline vector determination and the subsequent time derivatives, as well as capabilities/possibilities for advanced processing of interferometric observations. For precise orbit determination of Low-Earth Orbiting (LEO, 200-1500 km altitude) and Medium-Earth Orbiting (MEO, around 20 000 km altitude) satellites, accuracies at the cm level are achieved when making use of high-quality, dual-frequency Global Navigation Satellite Systems (GNSS) receivers [122][123][124][125]. For baselines around 200 km, a precision level as good as 0.5 mm has been achieved post-facto, making use of sophisticated dynamic force modelling and parameter estimation schemes [126][127][128]. ...
... The collision of Iridium 33 and Cosmos 2251 is believed to be the first accidental hypervelocity collision of two intact satellites [1]. In August 2016, significant orbit and attitude changes occurred to the Sentinel-1A, which were later proved to be the result of a 1 cm space debris impact [2]. Therefore, there have been many efforts to calculate collision probabilities [3], for collision avoidance [4] and to design space debris removal missions [5]. ...
... Additionally, a new orbit version (POE-E) has been computed at CNES for Jason-1, Jason-2, AltiKa and CryoSat-2, and finally, a new orbit version (GSFC std1504) has been derived at GSFC for TOPEX/Poseidon, Jason-1 and Jason-2. All these orbit solutions have been derived in the extended ITRF2008 reference frame (Altamimi et al., 2011) by using SLRF2008 (Pavlis et al., 2009), DPOD2008 (Willis et al., 2016) and IGS08 (Rebischung et al., 2012) station 30 solutions and are based on the GDR-E orbit standards (OSTM, 2015) or similar standards. The main differences of the GDR-E orbit standards with respect to the previous GDR-D (OSTM, 2015) orbit standards consist of i) using a more refined Earth Earth Syst. ...
... IERS C04 (Bizouard et al. 2018) is also a combined multi-technique ERP series but has a higher latency than Bulletin A and does not include predictions. It is based on the combined ERP series of the International GNSS Service (IGS, Johnston et al. 2017), the International VLBI Service (IVS, Nothnagel et al. 2016), the International Laser Ranging Service (ILRS, Pearlman et al. 2019), and the International DORIS Service (IDS, Willis et al. 2015). In addition, input data of individual VLBI analysis centers (ACs) and the ERP data of the International Terrestrial Reference Frame (ITRF) combination are considered. ...
... The standard deviations are also enlarged by a factor of 2:0. As discussed by Moreaux et al. (2016), one reason might be the reduction from six AC contributing to the ITRS 2008 realizations to only four AC contributing to the ITRS realizations 2014. ...
... In many regions, this was not sufficient to resolve the complex ocean dynamics in the coastal stripe (Woodworth et al. 2019). Finally, the ALT-TG comparison is impacted by the modeling adopted in the preprocessing of the datasets (Ray et al. 2021), technique-specific systematic biases (Couhert et al. 2015;Watson et al. 2015) and noise (Hughes and Williams 2010). ...
... State vectors are provided at intervals of 60 s. According to [16] the total absolute orbit error is as low as 10 cm RMS and the absolute radial error even lower than 5 cm RMS. Interpolating the intermediate state vectors using a higher-order polynomial certainly deteriorates the accuracy, but the errors are expected to remain small compared to the resolution capabilities of the ASAR system or the accuracy of a DEM. ...