Matthias Becker

Technical University of Darmstadt | TU · Instute of Geodesy, Dept. of Civil and Environmental Engineering

A reliable and highly-available estimation of the vehicle's dynamic state, which is providing integrity information, is essential for automated driving. A possible solution for this challenge is a modular structure consisting of a first level with redundant multi-sensor data fusion filters and a second level processing the first level's outputs. In...

In recent strapdown airborne and shipborne gravimetry campaigns with servo accelerometers of the widely used Q-Flex type, results have been impaired by heading-dependent measurement errors. This paper shows that the effect is, in all likelihood, caused by the sensitivity of the Q-Flex type sensor to the Earth's magnetic field. In order to assess th...

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...

Satellite gravity missions represent an important contemporary source of data for both hydrological and oceanic studies. The present study assesses the seasonal variability of Mediterranean Sea level using temporal observations from the Gravity Recovery and Climate Experiment (GRACE) mission. The GSM and GAD solutions from the German Research Centr...

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...

In recent years, it was shown that the quality of strapdown airborne gravimetry using a navigation-grade strapdown inertial measurement unit (IMU) could be on par with “classical” airborne gravimeters as the 2-axis stabilized LaCoste and Romberg S-type gravimeter. Basically, two processing approaches exist in strapdown gravimetry. Applying the indi...

For automated driving high-integrity localization information is essential. Often sensor fusion algorithms are used to fulfill this task. In this work three implementations of integrity concepts for such algorithms used in automated driving are compared. Therefore, requirements for sensor fusion algorithms used for automated driving functions of a...

A significant part of the World population lives in the coastal zone, which is affected by sea level rise and extreme events. Consistent and precise new measurements are needed to assess and predict these changes. New altimeter missions equipped with Synthetic Aperture Radar (SAR) mode provide more accurate sea level heights. In this work we analys...

New in this work is a new analytical derivation of a Delay-Doppler map model for Fully-Focused SAR, which includes the vertical wave particle motion and a more general surface representation. It was indeed already noticed in Egido and Smith (2017) that the open ocean surfaces decorrelate within the integration time interval, which is used in the FF...

Just as CryoSat-2, Sentinel-3 embarks on board a radar altimeter (SRAL) with the novel Synthetic Aperture Radar (SAR) mode that enables higher resolution and more accurate altimeter-derived parameters in the coastal zone, thanks to the reduced along-track footprint. Exploiting the SAR data in the recent years, many researchers have already proven t...

The study of climate change is an important field of research. Monitoring of atmospheric variability especially the tropospheric precipitable water vapor (PWV) is a powerful way to investigate climate change. Global navigation satellite systems (GNSS) provide a good tool for studying atmospheric parameters as GNSS signals along its path from the sa...

Eastern Mediterranean has been identified as an ideal natural laboratory for studying the kinematics and dynamics of plate interactions because of the wide variety of tectonic processes encompassed, including various stages of continental collision, subduction of oceanic lithosphere and associated back-arc spreading and continental extension. The t...

By convention the absolute bias in sea surface height (SSH) is the difference between the altimeter and the in-situ reference SSH heights above the Earth ellipsoid. Both the absolute and the relative bias of the CryoSat-2 and Sentinel-3A missions are derived in this study at four stations along the German coasts.

By convention the absolute bias in sea surface height (SSH) is the difference between the altimeter and the in-situ reference SSH heights above the Earth ellipsoid. Both the absolute and the relative bias of the CryoSat-2 and Sentinel-3A missions are derived in this study at four stations along the German coasts. Firstly, the coastal data processe...

Increase of water level in most of the world’s oceans and seas, including the Mediterranean, due to global warming may have a serious impact on the Nile Delta. The Nile Delta is considered as one of the most important regions in Egypt as more than 50% of the Egyptians are living there. To study the thread of a potentially sinking and flooding of th...

This paper introduces UNICARagil, a collaborative project carried out by a consortium of seven German universities and six industrial partners, with funding provided by the Federal Ministry of Education and Research of Germany. In the scope of this project, disruptive modular structures for agile, automated vehicle concepts are researched and devel...

Localization algorithms based on global navigation satellite systems (GNSS) play an important role in automotive positioning. Due to the advent of autonomously driving cars, their importance is expected to grow even further in the next years. Simultaneously, the performance requirements for these localization algorithms will increase because they a...

accepted

Unlike previous altimetric missions, the CryoSat-2 altimeter features a novel Synthetic Aperture Radar (SAR) mode that allows higher resolution and more accurate altimeter-derived parameters in the coastal zone, thanks to the reduced along-track footprint. The scope of this study is to quantify regionally the skills of CryoSat-2 SAR altimetry for d...

The paper summarizes the participation of the 6 FabSpaces to the population estimation (remote) pilot task at ImageCLEF 2017 Lab. FabSpace 2.0 is an open-innovation network for geodata-driven innovation that aims at improving universities contribution to the socioeconomic and environmental performance of societies. In the framework of the ImageCLEF...

Dynamic measurements of railway bridge displacements through microwave interferometry – Part 1: measurement method. The microwave interferometry is a rather new measuring technique, yet little-known in civil engineering applications. It allows the non-contact acquisition of structural displacements with accuracy in the sub-millimetre range at a sam...

The current trend of the technological progress in the field of structural dynamic measurements is veering towards non-contact, easy-to-use techniques. Among those, microwave interferometry is a rather new measurement method, yet little-known in civil engineering applications. It allows the non-contact synchronous measurement of structural deflecti...

In 2010 and 2011 airborne field campaigns were carried out with the goal to assess and compare the performance of various GNSS/IMU systems for airborne gravimetry. These so-called strapdown gravimetry systems are less expensive, more compact and less power consuming, while being easier to install and operate, than spring gravimeters. Besides the qu...

Cyclone Xaver pounded the North Sea on 5-6 December 2013 and reached its maximum in the German Bight the second day. Combined geodetic measurements from the SARAL/AltiKa satellite and from a local geodetic network detect cross-shelf and alongshore variations and loading vertical deformation. The cross-shelf root mean square differences between obse...

Cyclone Xaver pounded the North Sea on 5-6 December 2013 and reached its maximum in the German Bight the second day. Combined geodetic measurements from the SARAL/AltiKa satellite and from a local geodetic network detect cross-shelf and alongshore variations and loading vertical deformation. The cross-shelf root mean square differences between obse...

The terrestrial microwave interferometry is a rather new measuring technique, which allows the measurement of relative displacements of structures with an accuracy of up to 0.01 mm at a sampling rate of up to 4000 Hz, without any kind of instrumentation on the structure. Due to the high sampling frequency, capturing the vibrational behaviour of the...

Terrestrial microwave interferometry is a sophisticated technique in geodesy to measure relative displacements of a structure with a high accuracy of up to 0,01 mm at a sampling rate of 200 Hz from a distance of up to 1000 m. One of the big advantages of the method is that the object to be measured does not have to be instrumented or walked-on as t...

Die terrestrische Mikrowelleninterferometrie bietet die Möglichkeit, Deformati-onen von Objekten mit einer Genauigkeit von bis zu 0,01 mm bei einer hohen Abtastrate zu messen, ohne jegliche Instrumentierung der zu messenden Struktur vorzunehmen. Die hohe Abtastrate ermöglicht eine genaue Erfassung des Schwingungsverhaltens des zu untersu-chenden Ob...

Previous work has shown, that strapdown airborne gravimeters can have a comparable or even superior performance in the higher frequency domain (resolution of few kilometres), compared to classical stable-platform air gravimeters using springs, such as the LaCoste and Romberg (LCR) S-gravimeter. However, the longer wavelengths (tens of kilometres an...

The terrestrial microwave interferometry is a sophisticated technique from geod-esy to measure relative displacements of an existing position with a high accuracy up to 0.01 mm. One of the big advantages of this method is that the object to be measured does not necessarily have to be instrumented. In combination with structural analysis, the measur...

The subduction between Nubia and Eurasia and activities along the Red Sea, Gulf of Suez and Gulf of Aqaba may control the surface deformation in the north-eastern corner of the African continent. Using very few GPS stations in the Egyptian region, previous studies indicate northward motion of northern Nubia with respect to Eurasia of about 5mm/yr (...

To avoid the difficulties in fixing the carrier phase ambiguities, the time difference carrier phase approach is applied to a GPS/IMU tightly-coupled navigation system to eliminate the ambiguity between two successive GPS epochs, which can provide high velocity estimation accuracy. The carrier phases are carefully corrected before use. A modified m...

Estimability was introduced as a measure of how much observations can contribute to the estimation process for a linear system. Several publications analyse the estimabilities for integrated navigation systems, comprising a strapdown inertial measurement unit (IMU) and observations from global navigation satellite systems (GNSS). This concept will...

In the recent years, GPS only dual-frequency GNSS receivers are increasingly developing into multi-constellation, multi-frequency receivers. This development poses a new set of technical challenges. A key factor for precise GNSS applications is the stability of receiver induced inter-frequency/signal biases. The consequences of receiver induced bi...

The objective of this paper is to compare our PLRM altimeter products, derived by a PLRM processing of Cryosat-2 data in SAR mode, with PLRM products extracted from the RADS database and SAR products made available by ESRIN results. Test region is the German Bight. We distinguish between coastal zone and open sea, where distance to coast is larger...

For studying recent crustal movements and their relation to earthquake occurrence in large scales, the National Research Institute of Astronomy and Geophysics (NRIAG), Helwan, Cairo, Egypt started in 2006 the establishment of the Egyptian Permanent GPS Network (EPGN). Beginning with 4 stations in 2007, 15 stations were operational at the end of 201...

It has been recommended that the relative standard uncertainty of the numerical value of the Planck constant required for the redefinition of the kilogram should not exceed 2 × 10⁻⁸. To reach this goal using experiments based on a watt balance, the free-fall acceleration (g) traceable to the SI, at a given point and a given time, needs to be known...

Six years of GPS data have been reprocessed in ITRF2008 for a regional SAPOS CORS network in the federal state of Hesse with 25 stations and some anchor sites of IGS and EPN to derive accurate and consistent coordinate time series. Based on daily network solutions coordinate time series parameters like velocities, offsets in case of antenna changes...

We present a regional validation exercise in the German Bight of Level 2 Altimetry Data acquired by the CryoSat-2 mission in SAR (Synthetic Aperture Radar) Mode against in-situ data and model results in the time interval 2011-2012. The in-situ data are from a network of tide gauges, GNSS stations and offshore platforms in open sea and coastal zone....

Based on the reprocessing of a regional continuously operating reference station (CORS) network the effect of stochastic modelling on the significance of coordinate time series parameters is investigated. The aim is to identify a suitable stochastic model for the time correlated time series. It is needed as stochastic model of the time series data...

The new global gravity models represented by global spherical harmonics like EGM2008 require a high degree and order in their coefficients to resolve the gravity field in local areas; therefore, there are interests to represent the regional or local field by less parameters and to develop a parameter transformation from the global model to a local...

Sea level rise is among the most prominent indicators of global change, since it will (and has already done so) impact the lives of millions of people living close to the coast. Extreme events such as the flooding of New Orleans caused by hurricane Katrina, and the devastating tsunami that hit South East Asia 2004, underline the necessity to unders...

The passive hydrogen maser (PHM) of GIOVE-B and the latest generation of Rubidium clocks for GPS Block IIF satellites have both demonstrated a superior and highly competitive stability in ground tests. In practice, however, the apparent clock performance for GNSS users is limited by measurement errors and imperfections of the signal chain that affe...

The 8th International Comparison of Absolute Gravimeters (ICAG2009) took place at the headquarters of the International Bureau of Weights and Measures (BIPM) from September to October 2009. It was the first ICAG organized as a key comparison in the framework of the CIPM Mutual Recognition Arrangement of the International Committee for Weights and M...

We investigate the sea level rise in Indonesia during the period 1993–2011 using satellite altimetry and tide gauge data. Satellite altimetry indicates a positive sea level rise with mean of 4 mm/yr, which is higher than the global averaged mean sea level rise. At four tide-gauge stations the difference of the sea level trends from tide gauge and c...

The passive hydrogen maser of GIOVE-B and the new GPS Block IIF Rubidium clock have demonstrated a superior stability in ground tests. In practice, however, the apparent clock performance for GNSS users is limited by measurement errors and imperfections of the signal chain that affect the clock variance at different time scales. Within this paper,...

Abu-Dabbab area is characterized by high seismicity and complex tectonic setting, for these facts, a local geodetic network consisting of eleven geodetic benchmarks has been established. The crustal deformation data in this area are collected using the GPS techniques. Five campaigns of GPS measurements have been collected, processed and adjusted to...

For the first time, a dedicated release of the hydrology and water use model WaterGAP3, has been developed to spatially explicit calculate hydrological fluxes within river basins draining into the Mediterranean and Black Sea. The main differences between the new regional version of the global WaterGAP3 model and the previously applied global versio...

The mass-induced sea level variability and the net mass transport between Mediterranean Sea and Black Sea are derived for the interval between August 2002 and July 2008 from satellite-based observations and from model data. We construct in each basin two time series representing the basin mean mass signal in terms of equivalent water height. The fi...

The terrestrial microwave interferometry is a relatively young technique from the field of geodesy to measure relative displacements to an existing position with a high accuracy of up to 0.01 mm at a sampling rate of 200 Hz from a distance of up to 1000 m. Microwaves are being sent out along a line and the reflected waves can be analysed immediatel...

The availability of several GNSS with a multitude of signals offers great opportunities for improvements, but also great challenges. Multiple signals, frequencies and GNSS allow for a better identification and elimination of error sources and increase the availability, the reliability and the accuracy. But all this comes along with numerous new, cu...

The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters and 9 relative gravimeters participated in the ICAG/RGC campaign. Accurate...

High precision levelling is an indispensable method used to monitor benchmark and terrain stability at the Bureau International des Poids et Mesures (BIPM). Associated with the International Comparison of Absolute Gravimeters (ICAG), levelling measurements were carried out repeatedly over the past decades. A local gravity field strongly depends on...

A new Approach for GNSS Analysis in a Multi-GNSS and Multi-Signal Environment Over the coming years GPS and GLONASS will be modernised, whilst at the same time new systems like QZSS, Galileo, and Compass are launched. The modernisations of the existing and the deployment of new Global Naviagation Satellite Systems (GNSS) will make a whole range of...

Accurate gravity measurements were made to support the International Bureau of Weights and Measures (BIPM) watt balance (WB) project in association with the eighth International Comparison of Absolute Gravimeters (ICAG-2009) and the accompanying Relative Gravity Campaign (RGC-2009) at the BIPM in 2009. The goal of WB project is to determine the Pla...

The Bureau International des Poids et Mesures (BIPM), Sèvres, France, hosted the 7th International Comparison of Absolute Gravimeters (ICAG) and the associated Relative Gravity Campaign (RGC) from August to September 2005. ICAG 2005 was prepared and performed as a metrological pilot study, which aimed: • To determine the gravity comparison referen...

A two step method has been devised for the statistical inference of deformation changes. In the first step of this method and based on Procrustes analysis of deformation tensors, the significance of the change in a time or space series of deformation tensors is statistically analyzed. In the second step significant change(s) in deformations are loc...

A two step method has been devised for the statistical inference of deformation changes. In the first step of this method and based on Procrustes analysis of deformation tensors, the significance of the change in a time or space series of deformation tensors is statistically analyzed. In the second step significant change(s) in deformations are loc...

The problem of analyzing surface deformation of the Earth's crust in three-dimensions is discussed. The isoparametric and Lagrangian formulations of deformation are extended from 2D to 3D. Analytical and numerical investigation of problem conditioning proves that analyzing the 3D kinematics of deformation can be an ill-posed problem. The required m...

The goal of maintaining an accurate gravity network at the BIPM headquarters is twofold: firstly to support the International Comparison of Absolute Gravimeters (ICAG), and secondly to support the BIPM watt balance (WB) project, which aims at determining the Planck constant h or realizing a future new definition of the kilogram based on a fixed val...

Geodesy is the basis for all Geographic Information System (GIS) applications as it provides all information that is required for describing the location of a point at or close to the Earth. In this chapter the basic definitions, quantities and mathematical relations used in Geodesy are described. It should provide the important understanding of re...

The problem of analyzing surface deformation of the Earth's crust in three-dimensions is discussed. The isoparametric and Lagrangian formulations of deformation are extended from 2D to 3D. Analytical and numerical investigation of problem conditioning proves that analyzing the 3D kinematics of deformation can be an ill-posed problem. The required m...

The water mass variation in the Mediterranean Sea and Black Sea and mass exchange between the two basins is investigated using altimetry and GRACE measurements, oceanography and hydrology models over six years, between August 2002 and July 2008. The basin averaged signal is estimated from both steric-corrected altimetry and from hydrology-corrected...

Four years have gone since the start of the first Galileo In Orbit Validation Element (GIOVE)-A and nearly two years since the start of the second validation satellite GIOVE-B. Although results from the Galileo Experimental Sensor Stations (GESS) are published in several studies, the access to the GESS observation data is still limited to European...

In the framework of the GEOTECHNOLOGIEN program for Natural Hazard Mitigation several German research institutes collaborate in the `Exupéry' project. Goal of this project is the development of a Volcano Fast Response System (VFRS) which can be quickly deployed at any volcano in case of a volcanic crisis or unrest. The core of the VFRS consists of...

The earthquake true size and tsunami potential can be determined using GPS data up to only 15 minutes after earthquake initiation, by tracking the mean displacement of Earth's surface associated with the arrival of seismic waves (Blewitt, 2006). We are using this approach to get quick assessments of earthquakes' magnitudes. Data files with 1 Hz dat...

The GPS stations forming the CEGRN network in Central Europe are regularly observed since 1994. We report on the results of the systematic processing of the available data up to 2009. The analysis work has yielded the velocities of some 60 sites, covering a variety of Central European tectonic provinces, from the Adria indenter to the Tauern window...