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Geosynchronous SAR (GEO SAR) has better coverage and revisiting performance than the low Earth orbit SAR. Thus GEO SAR can implement the repeat-pass interferometry as its revisit time of 1 day and the orbit drift (forming baseline) induced by perturbation. In comparison, the twin GEO SAR formation configuration in which the slave satellite repeats the master satellite' track can realize shorter revisit...
This paper presents a novel semisupervised framework for detecting multi-class changes in bitemporal hyperspectral images. By taking advantages of the state-of-the-art unsupervised change representation technique and the advanced supervised classifiers, the proposed framework allows the generation of pseudo training samples associated with the no-change and each change class that learned from the...
We validate an absorption based radar retrieval algorithm of snow water equivalent (SWE) using X- and Ku-band backscatter with airborne SAR data. The bicontinuous dense media radiative transfer (Bic-DMRT) model is first applied to generate a look-up table of snow properties against backscattering at X- and Ku-bands. In the retrieval algorithm, the background scattering is subtracted from the total...
In the field of target detection in remote sensing images, lots of learning algorithms have been presented, among which support vector machine was widely utilized. However, this kind of vector represents only one pixel of a remote sensing image that ignores the spatial relationship of neighbors. Besides, with the increase of spatial resolution of remote sensing images, detail detection of targets...
In hyperspectral data analysis, hyperspectral data is often treated as a linear mixture problem with imposing two physical constraints, abundance sum-to-one constraint (ASC) and abundance non-negativity constraint (ANC). Thus, the constrained linear mixing model can be further understood via a geometric object, simplex, and results into a well-known N-finder algorithm (NFINDR). A new endmember finding...
Establishing causal relations between random variables from observational data is perhaps the most important challenge in today's Science. In remote sensing and geosciences this is of special relevance to better understand the Earth's system and the complex and elusive interactions between processes. In this paper we explore a framework to derive cause-effect relations from pairs of variables via...
TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurements) is an Earth observation radar mission that consists of a SAR interferometer built by two almost identical satellites flying in close formation [1]-[4]. With a typical separation between the satellites of 120 to 500 m a global Digital Elevation Model (DEM) with 2 m relative height accuracy at 12 m posting has been generated. While the...
Due to the restriction of the number of receivers, it is hard to realize high-resolution wide-swath (HRWS) imaging and moving target detection simultaneously for multichannel synthetic aperture radar (SAR) systems. This paper presents a novel moving target detection method in HRWS mode. A digital beamforming (DBF) technique in azimuth time domain is proposed to convert the ambiguous multichannel SAR...
We present a novel technique that allows us to detect, map and quantify changes on the Earth's surface in three-dimensions that occur at time scales of a few seconds. This rapid change detection capability is a byproduct of the development of a multichannel airborne lidar system that scans the target surface at three different times in a single aircraft pass. Results, capabilities, limitations and...
Airborne and terrestrial laser scanning techniques have been largely used for the reconstruction of high-resolution 3-D topography in the field of geosciences. In recent years, laser scanning has been also exploited on rock properties, biomass classification and carbon storage estimation. However, when laser spot collides partially against the target or even against undesirable background objects,...
This paper presents a novel approach to enhance the spatial resolution of Synthetic Aperture Radar(SAR) images. SAR images super-resolution(SR) reconstruction is challenging since SAR images has more complex structures. Inspired by the recent advance on natural image SR techniques, we propose a joint learning based strategy[1], combined with the characteristics of SAR image, to reconstruct HR SAR...
Surface motions are caused by various processes, e.g. (abandoned) mining, natural gas extraction, sinkholes, landslides and can cause damage to buildings, infrastructure, affect ecosystems, agriculture and the economic use of the geological underground by influencing the hydro(geo)logical setting. Advanced differential interferometric SAR processing techniques (A-DInSAR), e.g. Persistent Scatterer...
At present, various models are developed for soil moisture retrieval, but the application of polarimetric SAR data to retrieve soil moisture in sandy land is rare. Therefore, it is necessary to develop a method for retrieving soil moisture in sandy land. In this paper, we proposed a model to estimate the soil moisture in Hunshandake Sandy Land. The model does not need to take into account the surface...
Two automated approaches, including Bayesian probability thresholding and regression tree based methods were utilized to detect the surface water extent with training dataset from prior class probabilities of water and non-water from two datasets. First, prior water and non-water masks were classified using SRTM Water Body Dataset (SWBD) and long-term summarized Dynamic Surface Water Extent (DSWE)...
A new four component decomposition algorithm for urban targets delineation from PolSAR imagery was studied. First, a new correlation coefficient was introduced to describe characteristics of urban targets. The coefficient was the linear combination of two elements of a coherent matrix. Then, the coefficient was used to modify the volumetric scattering model component in Yamaguchi et al.'s four-component...
Airborne lidar is the tool best suited to provide timely updated maps for monitoring forest change in both horizontal and vertical dimensions. Still, it has been little used due to the scarcity of long-term time-series of lidar measurements. The NASA Jet Propulsion Laboratory Airborne Snow Observatory (ASO) is a landscape-level monitoring system that provides ongoing remote sensing measurements with...
Knowledge of calibration traceability is essential for ensuring the quality of data products relying on multiple sensors and especially true for imaging spectrometers. The current work discusses the expected impact that imaging spectrometers have in ensuring radiometric traceability for both multispectral and hyperspectral products. The Climate Absolute Radiance and Refractivity Observatory Pathfinder...
The linear array 3D imaging sensor uses a common optical path system to acquire image and point cloud data at the same time. The registration of these two types of data is realized by the common optical axis alignment and time synchronous control system. Since the image and point cloud data have different sampling frequencies; the process of generating colored point cloud needs to interpolate the...
This manuscript introduces a genetic algorithms (GA) method to design a kind of portable low natural frequency geophone which widely used in surveying deep geological structure. We attach a new electromagnetic feedback network to the two output poles of moving-coil geophone to improve the performance of low-frequency response. Because the feedback network is a complicated active analog circuit, it's...
In the traditional classification method, for the pixels, which the proportion of vegetation distribution is small, that is, the area occupied by vegetation in the pixel is less than half a pixel, they are often considered as a non-vegetation area. Such problems, in the highly developed cities, are the most common. Therefore, in order to more accurately compute the highly developed, especially hardened...
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