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The effective exploitation of the available huge SAR data archives in reasonable time-frames has motivated the development of P-SBAS, a parallel computing solution for the SBAS (Small BAseline Subset) processing chain. Hence, P-SBAS parallel solution represents a valuable tool for the analysis of the complex phenomena characterizing the surface deformation dynamics of Earth large areas, since it permits...
Angular super-resolution performance is the key problem in the field of radar imaging. In this paper, we propose an approach to radar angular super-resolution through deconvolution, which is able to increase the resolution of radar image beyond the limitation of system parameters. It relies on the Bayesian formulation approach that enables to incorporate the prior information about the system and...
Synthetic aperture radar (SAR) is an active microwave sensor which is able to produce high-resolution images with day and night capability. Traditionally, the image quality assessment of the SAR system is described by the response function of an isolated point target. However, some man-made targets which are placed together can not be distinguished clearly. As the point target has the characteristic...
The theory of compressed sensing (CS) indicates that the optimal reconstruction of an unknown ISAR signal with intrinsical sparsity can be achieved by solving a sparsity-driven optimization problem. Due to this property, a novel method to construct sparse basis is presented for ISAR image generation. We utilize discrete chirp fourier transform (dcft) and CLEAN to decompose the signal of interest into...
Many parameters are required for the measurement of the sea surface currents and the sea levels simultaneously by the along-track interferometry SAR (AT-InSAR). To estimate the elevation or the sea levels from the signals observed by the AT-InSAR, the method for synthesizing these received signals was developed. To evaluate the estimation method, the ground surface was observed by the cross-track...
The Multi-baseline synthetic aperture radar interferometry (InSAR) is capable of solving layover phenomena because of its resolving capability along the elevation dimension. Using baseline diversity of a multi-baseline InSAR system to overcome layover is essentially a matter of spectral estimation problem. The spectrum's period and the estimation resolution are influenced by the InSAR system parameters...
In this paper, a novel multi-baseline phase unwrapping approach is proposed based on maximum likelihood estimation (MLE) method. Topography phase gradient is acquired by fusing multi-baseline InSAR data. It is convenient to obtain unwrapped phase by using gradient integral. Since search interval is critical for the uniqueness and accuracy of solution, low-precision digital elevation model (DEM) is...
This paper addresses the evaluation of the digital elevation model (DEM) generated by single pass SAR interferometry using an X-band airborne SAR (Pi-SAR2). In this paper we describe the evaluation experiments by using corner reflectors and show the result of the height accuracy on DEM by the cross-track interferometric function of Pi-SAR2.
Spaceborne D-InSAR system is a kind of SAR satellite system aiming at differential interferometry application. It provides us a capability of measuring subtle deformation on the ground with phase difference. In this work, we focused on the system performance analysis theory as a first step to launch the research work on the overall spaceborne D-InSAR system. After the theoretical model and major error...
The geometry distortion phenomenon of SAR imaging arises in the mountainous scenarios due to the presence of strong terrain slopes. Because of phase discontinuities or the absence of valid phase, for single pass interferometric SAR (InSAR), it is difficult to recover accurate digital elevation model (DEM) in such areas. Fusion of two or more different aspects of InSAR data is practicable to deal with...
The standard TanDEM-X product meats HRTI-3 DEM specification and comes with a sample spacing of 12 m. We apply non-local means (NL) interferogram filtering to the TanDEM-X data. In this paper, we present modifications of the original NL filter which render it more appropriate and efficient for massive processing of TanDEM-X data. Further, we investigate the noise reduction properties as well as the...
Airborne single-pass SAR interferometry (InSAR) is a standard and operational technique for generating accurate and precise digital elevation models (DEM). But as DEM demand on fidelity and fast delivery grow over the years, the InSAR technology is challenged by the need of offering the same high-quality DEM over large areas on practically any type of surface and topography. The intent of this paper...
Within this manuscript a novel technique for joint Digital Elevation Model (DEM) reconstruction and deformation estimation is presented. In particular, a Maximum A Posteriori (MAP) estimator that makes use of Gaussian Markov Random Fields (MRF) is proposed. The advantage of the approach, with respect to classical Permanent Scatterers (PS) based techniques, consists of its ability to evaluate the height...
Phase Unwrapping (PhU) is the operation needed in order to generate 3-Dimensional height profile starting from Synthetic Aperture Radar (SAR) data acquired in the interferometric configuration. Due to the presence of height discontinuities (buildings) and due to the presence of noise, PhU becomes a difficult task to face in urban scenarios. In this paper we propose a new methodology especially thought...
SAR interferometry has long been regarded as an effective tool for wide-area topographic mapping in hilly and mountainous areas. However, quality of InSAR DEM product is usually affected by atmospheric disturbances and decorrelation-induced voids, especially for data acquired in repeat-pass mode. In this paper, we proposed an approach for improved topographic mapping by optimal fusion of multi-orbit...
The coherence in SAR interferometry is used as a parameters for change detection. However, it is difficult to quantitatively analyze the coherence value because the decorrelation come from diverse reasons and the unwanted targets naturally changes. In order to isolate the changed region by an accumulation of the volcanic ash, we analyze the reasons of the decorrelation. We estimate the temporal decorrelation...
This paper presents a use case of the Persistent Scatterer Interferometry (PSI) technique apply to Civil Engineering to monitor the dikes settlement on the Port of Barcelona. A geostatistical analysis of the two available datasets of PSI data have been made on a Geographic Information System to obtain a continuous deformation surface. This approach allows us to study the different subsidence velocities...
Due to the completion of the Three Gorges Dam and the limited geological environmental capacity, geological hazards occur frequently in the Three Gorges Reservoir region. Therefore, evaluating the stability of the riverbed and finding potential geological hazards become very meaningful. In this paper, Interferometrie SAR technology was used to monitor the ground deformation over selected areas, and...
We present a theoretical analysis for InSAR height measurement in sand-covered arid areas based on two-layer model. The influence of radar wave's penetration on height estimation is mainly considered. If the returned signal from the subsurface is dominant, InSAR is potential to measure the subsurface height. Taking the refraction at the interface and the change of propagation velocity in the sand...
The main objective of this research is to clarify backscattering characteristics of Persistent Scatterers (PS) used in Persistent Scatterer SAR Interferometry (PSInSAR) technique. In this study, we conducted both InSAR and In-situ observation analyses. Our test site is set to a campus area of College of Engineering, Nihon University, JAPAN, because we have already acquired variety of data on this...
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