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Persistent Scatterers for SAR Interferometry (PS-InSAR) tecnique allows monitoring the temporal evolution of a deformation phenomenon at millimeter level, via the generation of mean deformation velocity maps and displacement time series from a data set of acquired SAR images. However, the serious noises of multi-temporal SAR images make the selection of permanent scatters (PSs) difficult. In this...
Recently, microwave imaging has received a considerable amount of interest with respect to other imaging techniques. A large number of studies rely on microwaves, as a powerful electromagnetic tool to retrieve physical and electrical properties of penetrable and impenetrable objects. The capability of microwave signals to penetrate light opaque materials and sense distant or inaccessible objects with...
Identifying and characterizing objects in PolSAR images rely on proper backscattered signal models, correct segmentation algorithms and on exploiting the connections between the physical structure of the considered objects and their radar echos. The paper presents an ICA-based approach for characterizing physical properties of the objects on the Earth surface. Segmentation of PolSAR image is based...
Ocean-land segmentation is a basis for oceanic targets detection for SAR imagery. The traditional manual segmentation method can acquire a fairly good result, while it is unable to achieve a satisfying efficiency. Thus the manual method is unsuitable for batch processing. Ocean map based land masking method requires a priori information, which restricts its application. This paper presents an automatic...
This paper examines the benefits of using fully polarimetric SAR imagery for ship detection. There are three related aspects to the work. First, RadarSat-2 quad-pol stripmap imagery is used to compare the performance of various ship detection algorithms/methods. The comparison is based on the use of ROC curves. Second, circular spotlight SAR imagery is used to examine how detector performance varies...
In this paper, we describe a new automatic target recognition algorithm for classifying SAR images based on the PiXiT image classifier. It uses randomized sub-windows extraction and extremely randomized trees (extra-trees). This approach requires very little pre-processing of the images, thereby limiting the computational load. It was successfully tested on an extended version of the public standard...
In this paper, a new method for supervised classification of terrain types in polarimetric Synthetic Aperture Radar (Pol-SAR) images is proposed. This technique is a combination of the texture classification and the maximum likelihood classification based on the complex Wishart distribution for the polarimetric covariance matrix. The texture features are first extracted from the span image based on...
Markov random field method is a very active research field in image segmentation. In this paper, a new approach to the segmentation of SAR target chip image based on the Markov random field (MRF) and Maximum a Posteriori (MAP) rule is proposed. By statistical analysis of the different regions in the SAR target chip image, the valid segmentation algorithm for choosing the iteration initial value is...
The difference synthetic aperture radar interferometer (D-InSAR) is developed based on the synthetic aperture radar (InSAR) technique. It can be used to detect the earth surface deformation, fire hazard, earthquake and etc.. The imaging principle and data process procedure are introduced. The difference interfere process of the SAR data from Bam in Iran where earthquake happened on Dec. 26th, 2003...
Synthetic Aperture Radar (SAR) provides all day, all weather and long stand off range capability of imaging large areas of the Earth. Single pass Interferometric SAR (IFSAR) using a pair of vertically displaced phase centers can be effectively used to estimate height using SAR images corresponding to each phase center. In recent years, multiple input multiple output (MIMO) radar techniques have received...
In this paper, we propose a robust estimation method to coregistration error for synthetic aperture radar interferometry (InSAR) interferometric phase. In the method, the optimal joint data vector is determined, the true steering vector is computed according to the data vector, and then the beamforming technique with the steering vector is used to estimate the InSAR interferometric phase. The method...
The Army Research Laboratory (ARL) has recently developed the Recursive Side-lobe Minimization (RSM) technique (patent pending). The technique is integrated with a standard back-projection algorithm to form synthetic aperture radar (SAR) images with significant reduction in side-lobes and noise. We have achieved significant improvements in noise reduction by applying the RSM technique to our Ultrawideband...
The automated classification of operational sea ice satellite imagery is important for ship navigation and environmental monitoring. Annually, thousands of large synthetic aperture radar (SAR) scenes are manually processed by the Canadian Ice Service (CIS) and pixel-level interpretation is not feasible. Trained ice analysts divide SAR images into ”polygon” areas and then identify the number and type...
Pleasingly parallel algorithms such as filtered back-projection have been documented to enjoy significant speedups when ported to run on a graphics processor instead of a standard CPU. Presented here is a two-dimensional SAR backprojection implementation for a single GPU using the NVIDIA CUDA framework. Given that input range projections may be too large to fit in graphics memory, our implementation...
We describe an extensive data collection and analysis of change detection using VHF- and UHF-band SAR data. Two airborne systems (CARABAS-II: 22-82 MHz, LORA: 225-470 MHz) acquired data for multiple headings and incidence angles. Twenty one targets of five types were deployed in forest concealment. CARABAS-II gives the best performance for the target types investigated. Analysis of the data shows...
A new double-step fast CFAR scheme is proposed for multiple target detection in SAR images. The conventional multiple-cell based CFAR (MC-CFAR) detector is performed to find a potential target area. MC-CFAR carries out a quick search by which the CFAR sliding window is shifted by several cells for the reduced computational loads and it can also effectively reduce the small sized false alarm in the...
An algorithm of segmentation by using feature extraction techniques of Synthetic Aperture Radar (SAR) images in this paper. The segmentation processor are shown to be of interest for analysing SAR image data. The extracted and selected features are then used to train different neural-network based classifiers. Segmentation makes use of wavelet decomposition and unsupervised clustering based on PCA...
With continuing growth in sensor capabilities and database complexity, the analysis and understanding of large data sets becomes increasingly important. Numerous researchers have recently explored the geometry and topology of high contrast patches in natural images in an attempt to understand the underlying manifold of the data. The results show that the majority of natural image patches are best...
In this paper a new segmentation method for SAR images is presented which requires applying edge detector such as Sobel, Robert, Prewitt, or canny. Then, use edge information in order to estimate the threshold values required for image segmentation. Segmenting SAR images with low contrast using the proposed method was very satisfactory and the obtained results are very promising.
Phase gradient autofocus (PGA) algorithm has been proved to be a superior method for higher order phase error correction in SAR/ISAR image post processing. However, the accuracy of phase error estimation using traditional PGA algorithm is usually not guaranteed especially when there are several strong adjacent scatterers in a range bin. In this paper an improved iterative PGA approach based on adaptive...
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