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Antarctica is surrounded by ice shelves and glaciers of different sizes. Satellite imagery shows different feature patterns (e.g. crevasses, rifts) at their surfaces, which control the shape and the size of icebergs that calve from their seaward edges. An edge detection method was used to map and classify the surface features, considering their orientation relative to the calving front. Calved icebergs...
This study investigates the use of AISA optical airborne hyperspectral (2 m spatial resolution) and simulated satellite EnMAP (30 m) to produce detailed lithologic maps in a subarctic region (Nunavik, Canada) where ultramafic rock units associated with Ni-Cu-(PGE) mineralization are exposed in the presence of lichen coatings. Spectral mixture analysis methods were used to first derive image endmembers...
We have designed and developed a new airborne Ku-band Doppler radar, called KuROS, to prepare the CFOSAT satellite mission for measuring ocean surface wind and waves. The main characteristics of this new radar are presented, and first results obtained from a campaign held in 2013 illustrated. Both intensity and Doppler information are used to estimate the directional spectra of ocean waves. Radar...
In this study, vegetation optical depth from ESA's Soil Moisture and Ocean Salinity (SMOS) satellite mission is combined with other existing remote sensing, meteorological and literature data in order to obtain values of gravimetric vegetation water content (Mg). The methodology combines an effective medium model valid at passive microwave frequencies with a vegetation dielectric constant model. The...
In Synthetic Aperture Radar (SAR) interferometry(InSAR), we generally expect that there is only one unique dominant scatterer in a pixel. To make a SAR interferogram, we have to observe every place twice. Between the observations, the dominant scatterer is expected to unchange. However, in actual situations, there are multiple scatterers in one pixel, and a dominant one may change observation by observation...
The physically-based vegetation canopy reflectance model is the basis for accurate inversion of important vegetation parameters. According the interactive process between photons and canopy, canopy reflectance could be divided into two parts: single scattering and multiple scattering reflectance. Recollision probability is a useful tool linking leaf optical properties to canopy reflectance or absorption...
The development of microwave remote sensing models for the monitoring of vegetation has received wide attention in recent years. For vegetation in the tropics, it is necessary to consider a dense medium model for the theoretical modelling of the microwave interaction with the vegetation medium. In this paper, a multilayer model based on the radiative transfer theory for a dense vegetation medium is...
A general explicit closed-form expression of high-order perturbative solutions of the problem of radiation and propagation electromagnetic (EM) fields in a layered structure with multilayer rough interfaces is developed in the framework of classical small perturbation method (SPM). The high-order SPM expression of the electric and magnetic fields in each region of the rough-layered structure is provided...
In this paper, an adaptive patch-based filter for Synthetic aperture Radar (SAR) Interferometric phase in the Fourier transform complex domain is proposed. The proposed filter fully utilizes the properties of locally planar terrain phase noise model so that the noise can be suppressed according to the local level of noise. Moreover, the denoising performance of the proposed filter is further improved...
Wide band electromagnetic (EM) scattering characteristics of randomly rough surface in the terahertz (THz)frequency range are investigated through the use of finite difference time domain(FDTD) algorithm. Then the scattering characteristics of double negative materials(DNM) randomly rough surface are investigated further. It's worth nothing that in order to avoid introducing numerical divergence,...
A rain column model is used analyze back scattering from precipitation in the presence of hail. Backscattering from the entire precipitation column comprising hail and rain that accounts for multiple-scattering and boundary interactions are determined by solving the vector radiative transfer (VRT) equations. Precipitation column is partitioned into sublayers and Mie scattering calculation is used...
Radar scattering center separation by means of the statistical properties of the data allows an algorithm to adapt to the scattering environment. Through the assumption of non-Gaussianity for scattering centers of interest it is feasible to employ a source separation technique base on finding the most non-Gaussian features within the data. A well known technique to accomplish extraction of components...
Data acquired by the last generation of SAR sensors over urban areas, thanks to high resolution, can reveal the presence and main features of buildings. Unfortunately geometric distortions introduced by system geometry and signal multiple reflections make SAR images very complex so we need a scattering model supporting both the visual inspection and the processing for information retrieval. In this...
High resolution imaging is an important trend for SAR. The wide bandwidth signal is a must for high resolution. The error of traditional model based on the narrow bandwidth system may be inevitable for high resolution imaging. In this paper, a general SAR echo model is derived for the wide bandwidth system, and we also get the error factor between the traditional and general model. By simulating the...
We present a robust, rapid, and computationally efficient forward solver to compute electromagnetic (EM) fields produced by active, induction-regime remote sensing instruments embedded in subsurface, planar-stratified environments containing media of arbitrary anisotropy and loss. The algorithm is based on the robust evaluation of the spectral integral representation for the fields in such complex...
We examined the forward reflection from a randomly rough lossy dielectric surface and the accuracy of the forward reflection model. The moment method could be used to compute the forward reflection coefficient. We also examined the effect of correlation length on various correlation length and RSM height. The forward reflection coefficient of a randomly rough surface is computed by the (1) or (2),...
A comparison between the algorithm for Land Aerosol property and Bidirectional reflectance Inversion by Time Series technique (LABITS) and a daily estimation of aerosol optical depth (AOD) algorithm (AERUS-GEO) over land surface using MSG/SEVIRI data over North Africa is presented. To obtain indications about the quantitative performance of two AOD retrieval methods mentioned above, daily SEVIRI AOD...
This paper investigates the joint use of SAR image and optical image for stereo positioning. To obtain the 3D information of target in the real scene, the geometric relationship between optical radar and SAR are initially established. Then, two angle equations of optical data and a slant range equation of SAR data are jointly utilized to derive the 3D coordinate of target. To further analyze the impact...
Optronic processing is a promising way to real-time highresolution SAR image formation. Rang migration is inevitable in SAR imaging, especially in the case of highresolution SAR system, range cell migration correction (RCMC) is considered in nature. A solution of RCMC by using optronic processing is presented in this paper. In this optronic solution, most computation is undertaken by optical devices,...
This paper presents a two-dimensional (2-D) generalized omega-K algorithm for high-precision processing of the data of missile-borne Synthetic Aperture Radar (SAR) with constant acceleration. The almost adequate expression of the 2-D spectrum of the echo signal is obtained by the Method of Series Reversion (MSR). Then a 2-D generalized Stolt interpolation is carried out. The proposed algorithm can...
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