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In order to solve the parameters estimation problem caused by the moving target with the micro motion in the GEOSAR model, a technique based on time-frequency distribution and least squares estimation is introduced. The model of micro-motion part can be seen as a narrow band stochastic process, which is close to the reality of the motion. The method is used to estimate the parameters of the translation...
This paper presents a standardized quality criteria to evaluate the 3D point cloud model of the indoor building which is based on point cloud's data accuracy, the prior characteristics of the building and the coincidence errors of the point cloud model. Our assessment framework involves three steps: the point cloud data acquisition, model generation and quality evaluation. In model generation progress,...
Synthetic Aperture Radar (SAR) Tomography is a multi-temporal technique which can reconstruct the 3D profile of a scene. One of its main features consists in the ability to detect the presence of multiple Persistent Scatterers (PS) within the same resolution cell. This paper aims to investigate the super-resolution capabilities of SAR Tomography, by detecting targets situated at a distance which is...
The traditional ortho-rectification technique for remotely sensed imagery, which is performed on the basis of ground image processing platform, has been unable to meet the timeliness requirements. To solve this problem, this paper presents the research on ortho-rectification technique based on field programmable gate array (FPGA) platform, which can be implemented onboard and spaceborne for a real-time...
Airborne acquisition and ground-view 3D point cloud provide complementary 3D information at city scale. A complete but lacks ground-view details, while the latter is incomplete for higher floors and severe occlusion. In this paper, First, a volumetric fusion method based on graph cuts were applied for fusing of airborne and terrestrial 3D LiDAR data. Second, we propose a method of constraints based...
This paper proposes the phase error compensation algorithm of the wide band chirp generator for the synthetic aperture radar (SAR) use. The proposed algorithm dynamically calculates the phase error of transmitting chirp to reduce spurious of signal. In addition, it uses the curve fitting method and feedback when the desired signal are set by user. Numerical results show that the proposed algorithm...
Variations in the updated (1842–2016) Estonian sea level records are interpreted using the latest, extensive findings from the studies of crustal movements in Estonia and an attempt has been made to separate the main sea level trend components. Per recent semi-empirical land uplift (LU) model NKG2016LU_lev, the LU relative to geoid in Estonia (0.3–3.4 mm/yr) partly compensates for the global sea level...
In recent years, the science of hyperspectral remote sensing has huge development in virtue of the integration of low-cost lightweight hyperspectral sensors and unmanned aerial vehicles (UAVs). As an alternative of manned aircraft, UAV has some unique advantages enabling the researchers acquire the hyperspectral images of their interest area flexibly and promptly. This review focuses on the recent...
Structure-From-Motion (SFM) method is based on the same scene and different angles of the captured sequence of image, then calculate the feature points in the photogrammetric coordinate system of three-dimensional coordinates and camera parameters. SFM can directly generated orthophoto map just by captured overlapping images, but mosaicking accuracy has not to be verified. The purpose of this study...
We have developed an unmanned aerial system consisting of a compact sounding radar operating in the frequency bands of 14 and 35 MHz integrated into a fixed-wing UAV for remote surveys of glaciers and ice-sheets. The system is capable of collecting coherent sounding measurements along multiple parallel tracks. With the use of differential GPS for precise trajectory determination, we demonstrate multipass...
The Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (SNPP) satellite uses its 14 reflective solar bands to passively collect solar radiant energy reflected off the Earth. The Level 1 product is the geolocated and radiometrically calibrated top-of-the-atmosphere solar reflectance. The absolute radiometric uncertainty associated with this product includes...
We improved the repeat-pass InSAR processing capability for the L-band UAVSAR airborne synthetic aperture radar in order to support time-series analysis of repeat zero-baseline observations as well as multiple baseline observations for TomoSAR imaging. This new capability enabled us to conduct tomographic experiments in Gabon during the AfriSAR deployment in support of vegetation structure studies...
The hydrologic cycle is the process, powered by the sun's energy, which moves water between the oceans, the sky, and the land. Atmospheric scientists look for data that would help understand and eventually predict the atmospheric phenomena. The AMSR instruments have obtained atmospheric data since 2002, which are helping in understanding the Earth's atmosphere. Long-term atmospheric products sets...
Albacore tuna (Thunnus alalunga) is one of the important commercial species of the longline fishery in the southern Indian Ocean (SIO). The satellite-based oceanographic data of net primary production (NPP), sea-surface temperature (SST), sea surface salinity (SSS), mixed layer depth (MLD), sea-surface height (SSH) and eddy kinetic energy (EKE), were used to evaluate the effects of oceanographic conditions...
Constructing the high spatio-temporal NDVI time series data is necessary to study the urban vegetation phenology, and the response relationship between vegetation phenology and temperature changes can better understand the urban ecological conditions. In this paper, taking the typical area in Nanjing City as study area, urban vegetation phenology is deriving from HJ NDVI time series. Two ways of the...
Maritime pollution by chemical products occurs at much lower frequency than spills of oil, however the consequences of a chemical spill can be more wide-reaching than those of oil. While detection and characterization of hydrocarbons have been the subject of numerous studies, detection of other chemical products at sea using remote sensing has been little studied and is still an open subject of research...
More and more attention has been paid to taking the Earth as a whole for researching. Though space-borne and airborne platform have acquired various data from the Earth, the existing Earth observation system lack the ability of long-term continuous observation at a global scale. Three-polar regions include the Arctic, Antarctic and Tibet Plateau, which characterized by its large scale and need long-term...
Satellite-derived rainfall can be a potential source for flood detection and monitoring in ungauged watersheds. This study investigated the hydrological utility of satellite-derived rainfall through rainfall-runoff modeling. The results showed that the COMS satellite rainfall led to large underestimation in runoff discharge indicating that a preprocessing scheme such as bias correction or adjustment...
Previously, we developed two NMF algorithms named QL1-NMF using quasi-L1 norm for analyzing environmental ELF magnetic field measurements. When the data includes many outliers, the QL1-NMF algorithms returned better results than other BSS algorithms using L1 norm. However, the derivative of cost function in our first algorithm was not based on a monotonically increasing function. This problem decreased...
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