Searched for: author%3A%22van+Leijen%2C+F.J.%22
(1 - 20 of 35)

Pages

document
Brouwer, W.S. (author), Wang, Y. (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
InSAR enables the estimation of displacements of (objects on) the earth's surface. To provide reliable estimates, both a stochastic and mathematical model are required. However, the intrinsic problem of InSAR is that both are unknown. Here we derive the Variance-Covariance Matrix (VCM) for double differenced phase observations for an arc, i.e...
conference paper 2023
document
Tondaś, Damian (author), Ilieva, Maya (author), van Leijen, F.J. (author), van der Marel, H. (author), Rohm, Witold (author)
The continuous monitoring of ground deformations can be provided by various methods, such as leveling, photogrammetry, laser scanning, satellite navigation systems, Synthetic Aperture Radar (SAR), and many others. However, ensuring sufficient spatiotemporal resolution of high-accuracy measurements can be challenging using only one of the...
journal article 2023
document
Conroy, Philip (author), van Diepen, S.A.N. (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
We introduce the term loss-of-lock to describe a specific form of coherence loss that results in the breakage of a synthetic aperture radar interferometric (InSAR) time series. Loss-of-lock creates a specific pattern in the coherence matrix of a multilooked distributed scatterer (DS) by which it may be detected. Along with identification, we...
journal article 2023
document
Mulder, G. (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
The observed phase in time series of interferometric synthetic aperture radar (InSAR) products is a superposition of various components. Differential topography, line-of-sight displacements, and differential atmospheric delays are the main contributions and need to be disentangled to derive accurate digital elevation model (DEM), deformation,...
journal article 2023
document
Conroy, Philip (author), van Diepen, S.A.N. (author), Van Asselen, Sanneke (author), Erkens, Gilles (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
Phase unwrapping, also known as ambiguity resolution, is an underdetermined problem in which assumptions must be made to obtain a result in SAR interferometry (InSAR) time series analysis. This problem is particularly acute for distributed scatterer InSAR, in which noise levels can be so large that they are comparable in magnitude to the...
journal article 2022
document
Hu, F. (author), van Leijen, F.J. (author), Chang, L. (author), Wu, Jicang (author), Hanssen, R.F. (author)
Synthetic aperture radar (SAR) missions with short repeat times enable opportunities for near real-time deformation monitoring. Traditional multitemporal interferometric SAR (MT-InSAR) is able to monitor long-term and periodic deformation with high precision by time-series analysis. However, as time series lengthen, it is time-consuming to...
journal article 2022
document
Tiberius, C.C.J.M. (author), van der Marel, H. (author), Reudink, R.H.C. (author), van Leijen, F.J. (author)
This book provides an introduction, at academic level, into the field of surveying and mapping. The book has been compiled based on hand-outs and readers written for the third-year course Surveying and Mapping, in the bachelor program Civil Engineering at Delft University of Technology. This book covers a wide range of measurement techniques,...
book 2022
document
Mulder, G. (author), van Leijen, F.J. (author), Barkmeijer, Jan (author), De Haan, Siebren (author), Hanssen, R.F. (author)
Numerical weather prediction (NWP) models are used to predict the weather based on current observations in combination with physical and mathematical models. Yet, they are limited by the spatial density and the accuracy of the available observations. Satellite radar interferometry (InSAR) is known to be extremely sensitive to the 3D...
journal article 2022
document
Conroy, Philip (author), van Diepen, S.A.N. (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
We present a novel InSAR processing scheme which combines point scatterer (PS) and distributed scatter (DS) approaches in a hybrid framework along with contextual information about the environment under study. Data such as land parcel divisions, precipitation and temperature are integrated into the processing pipeline in order to produce...
conference paper 2022
document
van Natijne, A.L. (author), Bogaard, T.A. (author), van Leijen, F.J. (author), Hanssen, R.F. (author), Lindenbergh, R.C. (author)
Landslides are a major geohazard in hilly and mountainous environments. In-situ inspection of downslope motion is costly, sometimes dangerous and, requires prior knowledge of the existence of a landslide. Remote sensing from space is a way to detect and characterize landslides systematically at large scale. Interferometric Synthetic Aperture...
journal article 2022
document
Czikhardt, Richard (author), van der Marel, H. (author), van Leijen, F.J. (author), Hanssen, R.F. (author)
The estimation of Signal-to-Clutter Ratio (SCR) of a radar point target, such as a corner reflector, is an essential step for synthetic aperture radar (SAR) interferometry and positioning, as it influences the phase measurement variance as well as the absolute positioning precision. The standard method to estimate the SCR of a point target...
journal article 2021
document
Reinders, K.J. (author), van Leijen, F.J. (author), Hanssen, R.F. (author), Korff, M. (author)
This paper investigates the use of InSAR data during shield tunnel construction when short-term settlements occur within a few days. Additionally, the long-term settlement, which occur over several years, in the vicinity of these tunnels are evaluated with inSAR. The North-South Line in Amsterdam is used as a case study for this research. We...
conference paper 2021
document
Reinders, K.J. (author), Hanssen, R.F. (author), van Leijen, F.J. (author), Korff, M. (author)
In this work, we investigate if, when, and how satellite InSAR can be used for evaluating surface settlements that occur during shield tunnelling in soft soil areas. We evaluate the applicability of InSAR prior, during, and after tunnel construction. Special emphasis is placed on the influence of the InSAR phase ambiguities in relation to short...
journal article 2021
document
Ketelaar, Gini (author), Bähr, Hermann (author), Liu, Shizhuo (author), Piening, Harry (author), van der Veen, Wim (author), Hanssen, R.F. (author), van Leijen, F.J. (author), van der Marel, H. (author), Samiei Esfahany, S. (author)
This paper describes several geodetic studies that consolidate the reliability and precision of monitoring subsidence due to hydrocarbon production: the deployment of Integrated Geodetic Reference Stations (IGRS); the application of high resolution InSAR; the comparison of different GNSS processing methodologies; the implementation of an...
conference paper 2020
document
Yang, M. (author), Dheenathayalan, P. (author), López-Dekker, Paco (author), van Leijen, F.J. (author), Liao, Mingsheng (author), Hanssen, R.F. (author)
Persistent Scatterer Interferometry (PSI) is a time series remote sensing technique to estimate displacements of geo-objects from the interferometric phases of selected Persistent Scatterers (PS). The relative position of a scatterer within a resolution cell causes an additional phase contribution in the observed phase, which needs to be...
journal article 2020
document
Özer, I.E. (author), Rikkert, S.J.H. (author), van Leijen, F.J. (author), Jonkman, Sebastiaan N. (author), Hanssen, R.F. (author)
We hebben in Nederland ongeveer 20.000 km waterkeringen en het is kostbaar en tijdrovend om deze regelmatig fysiek te inspecteren. Met radarsatellieten wordt deformatie op meer plekken, vaker, en nauwkeuriger gemeten. Hierdoor kan het gedrag van keringen continu worden gemonitord en kan afwijkend gedrag vroegtijdig worden gedetecteerd. Deze...
journal article 2019
document
Özer, I.E. (author), Rikkert, S.J.H. (author), van Leijen, F.J. (author), Jonkman, Sebastiaan N. (author), Hanssen, R.F. (author)
Levees are critical in providing protection against catastrophic flood events, and thus require continuous monitoring. Current levee inspection methods rely on limited information obtained by visual inspection, resulting in infrequent, localized, mostly qualitative and subjective assessments. This hampers the timely detection of problematic...
journal article 2019
document
Hu, F. (author), van Leijen, F.J. (author), Chang, Ling (author), Wu, Jicang (author), Hanssen, R.F. (author)
Multi-temporal interferometric synthetic aperture radar (MT-InSAR) can be applied to monitor the structural health of infrastructure such as railways, bridges, and highways. However, for the successful interpretation of the observed deformation within a structure, or between structures, it is imperative to associate a radar scatterer...
journal article 2019
document
Özer, I.E. (author), van Leijen, F.J. (author), Jonkman, Sebastiaan N. (author), Hanssen, R.F. (author)
Levees are critical systems in safeguarding an area against catastrophic flooding events with potential fatalities and economic losses. Current monitoring methods of levees highly rely on expert judgement, resulting in infrequent and subjective assessments of their status. Satellite radar imaging, in particular using interferometry (InSAR),...
journal article 2018
document
Özer, I.E. (author), van Leijen, F.J. (author)
Satellietradarinterferometrie (InSAR) maakt het mogelijk om voor bepaalde objecten op het aardoppervlak deformaties op mm niveau te meten. De techniek wordt onder andere toegepast voor het monitoren van de stabiliteit van verschillende typen infrastructuur, zoals wegen en spoorwegen. De voordelen van satellietradarinterferometrie zijn dat grote...
report 2018
Searched for: author%3A%22van+Leijen%2C+F.J.%22
(1 - 20 of 35)

Pages