A5075125735- Synthetic Aperture Radar (SAR) Applications and Techniques
- Advanced SAR Imaging Techniques
- Soil Moisture and Remote Sensing
- Cryospheric studies and observations
- Seismic Imaging and Inversion Techniques
- Geophysical Methods and Applications
- Landslides and related hazards
- Seismic Waves and Analysis
- Geophysics and Gravity Measurements
- Remote Sensing and LiDAR Applications
- Methane Hydrates and Related Phenomena
- Microwave Imaging and Scattering Analysis
- Underwater Acoustics Research
- Reservoir Engineering and Simulation Methods
- Optical measurement and interference techniques
- Advanced Vision and Imaging
- Hydraulic Fracturing and Reservoir Analysis
- Soil Geostatistics and Mapping
- Arctic and Antarctic ice dynamics
- Antenna Design and Optimization
- Structural Health Monitoring Techniques
- Drilling and Well Engineering
- Radar Systems and Signal Processing
- Ocean Waves and Remote Sensing
- Ultrasonics and Acoustic Wave Propagation
Politecnico di Milano
2014-2024
Consorzio di Bioingegneria e Informatica Medica
2007-2015
Ingegneria dei Sistemi (Italy)
2015
Fondazione Politecnico di Milano
2011
Leonardo (United Kingdom)
2008-2009
University of California, Berkeley
2004
Planetary Science Institute
2004
Tele-Rilevamento Europa (Italy)
2002-2003
Stanford University
1984
ExxonMobil (United States)
1980
Temporal and geometrical decorrelation often prevents SAR interferometry from being an operational tool for surface deformation monitoring topographic profile reconstruction. Moreover, atmospheric disturbances can strongly compromise the accuracy of results. The authors present a complete procedure identification exploitation stable natural reflectors or permanent scatterers (PSs) starting long temporal series interferometric images. When, as it happens, dimension PS is smaller than...
Discrete and temporarily stable natural reflectors or permanent scatterers (PS) can be identified from long temporal series of interferometric SAR images even with baselines larger than the so-called critical baseline. This subset image pixels exploited successfully for high accuracy differential measurements. The authors discuss use PS in urban areas, like Pomona, CA, showing subsidence absidence effects. A new approach to estimation atmospheric phase contributions, local displacement field...
Permanent Scatterer SAR Interferometry (PSInSAR) aims to identify coherent radar targets exhibiting high phase stability over the entire observation time period. These often correspond point-wise, man-made objects widely available a city, but less present in non-urban areas. To overcome limits of PSInSAR, analysis interferometric data-stacks should aim at extracting geophysical parameters not only from point-wise deterministic (i.e., PS), also distributed scatterers (DS). Rather than...
SAR surveys from separate passes show relative shifts of the ground wavenumber spectra that depend on local slope and off-nadir angle. The authors discuss exploitation this spectral shift for different applications: 1) generation "low noise" interferograms benefiting phase unwrapping, 2) quick-look interferograms, 3) decorrelation reduction by means tunable systems (TINSAR), 4) range resolution enhancement, 5) combination data gathered platforms (airborne satellite) a "long-time coherence"...
The focusing of synthetic-aperture-radar (SAR) data using migration techniques quite similar to those used in geophysics is treated. algorithm presented works the omega -k/sub x/ domain. Because time delays can be easily accommodated with phase shifts that increase linearly , range poses no problem. described plane geometry first, where and history exactly matched. effects sphericity Earth, Earth's rotation, satellite trajectory curvature are taken into account, showing theoretically...
High-resolution interferometric synthetic aperture radar (InSAR) permanent scatterer data allow us to resolve the rates and variations in of slow-moving landslides. Satellite-to-ground distances (range changes) on landslides increase at 5 7 millimeters per year, indicating average downslope sliding velocities from 27 38 year. Time-series analysis shows that displacement occurs mainly during high-precipitation season; 1997–1998 El Niño event, range change increased as much 11 The observed...
Spaceborne differential radar interferometry has proven a remarkable potential for mapping ground deformation phenomena (e.g., urban subsidence, volcano dynamics, coseismic and postseismic displacements along faults, as well slope instability). However, full operational capability not been achieved yet due to atmospheric disturbances phase decorrelation phenomena. These drawbacks can often be-at least partially-overcome by carrying out measurements on subset of image pixels corresponding...
This paper presents the results of a blind experiment that is performed using two pairs dihedral reflectors. The aim was to demonstrate interferometric synthetic aperture radar (InSAR) measurements can indeed allow displacement time series estimation with submillimeter accuracy (both in horizontal and vertical directions), provided data are properly processed impact <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> as well atmospheric...
Longer wavelength synthetic aperture radars (SARs) are precious in the remote sensing of forested areas, being sensitive to contributions from whole vegetation layer and ground below. The electromagnetic properties such retrieved multipolarimetric acquisitions, whereas their vertical structure is multibaseline acquisitions through tomographic imaging. Combining baseline polarization diversity provides most information, allowing decomposition SAR signal into ground- volume-only contributions....
Various techniques are described to measure, small displacements of television images. If two successive video frames considered, their differences approximately a linear combination the components displacement object. all points frame undergo same movement, then velocity estimation problem is solved using estimation. However, if some belong moving object and others background, can be stated in way only an algorithm available segment image into fixed areas. Afterwards, applied area only. In...
This paper presents a technique for overcoming the problem of tissue absorption in emission tomography. Given set equispaced projections interval (0, 2π), it is possible to derive an exact formula recovering spectrum image. The obtained by solving linear partial-differential equation that links derivatives with respect and spatial frequencies. Examples application synthetic real data are given.
Multibaseline synthetic aperture radar (SAR) interferometry can be exploited successfully for high-quality digital elevation model (DEM) reconstruction, provided that both noise and atmospheric effects are taken into account. A weighted combination of many uncorrelated topographic profiles strongly reduces the impact phase artifacts on final DEM. The key issue is weights selection. In present article a wavelet domain approach proposed. Taking advantage particular frequency trend distortion,...
Synthetic aperture radar interferometry is limited by temporal and geometrical decorrelation. Permanent scatterers (PSs) are helpful to overcome these problems, but their density in agricultural out-of-town areas not always sufficient. The forthcoming availability of satellite platforms with thinner orbital tubes shorter revisit times will enhance the use interferogram stacks, which usable for distributed progressively decorrelating targets, like those found areas. To estimate possibilities...
A signal/noise separation must recognize the lateral coherence of geologic events and their statistical predictability before extracting those components most useful for a particular process, such as velocity analysis. Events with recognizable we call signal; rest term noise. Let us define “focusing” increasing independence samples some invertible, linear transform L. By central limit theorem, focused signal become more non‐Gaussian; same L defocus noise make it Gaussian. measure F defined...
The retrieval of above-ground biomass (AGB) in dense tropical forests using synthetic aperture radar (SAR) images is widely recognized as a challenging task. first difficulty arises from the decrease sensitivity backscattered intensity to at high values, often referred backscatter saturation effect. At P-band, can occur values higher than about 300 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex...
A bstract Constant offset sections can be mapped to a fixed and compared in order provide method of velocity analysis. The direct mapping zero prior stack might an alternative processing procedure NMO stack. main advantage such would lie the correct treatment cross‐dips, but interpretational advantages also follow from performance partial stacks biased either high or low information.
Synthetic aperture radar (SAR) data collected over a 2-D synthetic can be processed to focus the illuminated scatterers in 3-D space, using number of signal processing techniques generally grouped under name SAR tomography (TomoSAR). A fundamental requirement for TomoSAR is have precise knowledge platform position along aperture. This not easily met case where formed by collecting different flight lines (i.e., 1-D apertures) repeat-pass fashion, which typical airborne and spaceborne TomoSAR....
The research and improvement of methods to be used for deformation measurements from space is a challenge. From the previous 20 years, time series Synthetic Aperture Radar (SAR) interferometry techniques have proved their ability provide millimeter-scale over time. This paper aims review such developed in last twenty years. We first recall background interferometric SAR (InSAR). then an overview InSAR literature, describing principles advancements. Finally, we highlight challenges future...