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PAU/PARIS End-to-end Performance Simulator (P2EPS) has been developed for studying and design tools for GNSS-R space mission. For the purpose of accuracy and various scenario, P2EPS has recently improved in many features. Especially, the wide range of the simulation inputs enables to simulate the upcomming GNSS-R space missions. This paper presents the recent improvement of the P2EPS.
This study presents the feasibility of sea waves monitoring using the P(Y) & C/A ReflectOmeter (PYCARO) instrument which employs a novel Global Navigation Satellite Sys tems Reflectometry (GNSS-R) correlation technique. To that end, an experiment over the wave channel surface of the civil engineering school of UPC (Barcelona, Spain) is performed using a signal generator to simulate the GPS satellites...
Reflectometry using Global Navigation Satellite System's signals of opportunity (GNSS-R) was originally conceived for mesoscale altimetry [1], although its applicability to sea state determination, soil moisture, vegetation, snow monitoring… has already been demonstrated. In December 2012 the Phase A studies of ESA's PAssive Reflectometry and Interferometry System In-orbit Demonstration (PARIS IoD)...
Full Polarization Interferometric Radiometer (FPIR) is concept of one dimensional synthetic radiometer. This paper introduces the design of the FPIR antenna. A novel linear array antenna is described with emphasis on the simulation of the antenna pattern, design of the stripline feeding network and simulation of the polarimetric isolation.
Design limitations for synthetic aperture radiometer are quantitatively analyzed. Firstly, the image quality of a small scaled system with a few baselines is analyzed. The image quality is getting poorer due to the truncation in the spatial frequency domain while the number of baselines is getting fewer. This is called the lower limit for the design. Secondly, the design limitation for a large scaled...
Reflectometry using Global Navigation Satellite System's signals of opportunity (GNSS-R) was originally conceived for mesoscale altimetry, but it can be applied to sea state determination (i.e. wind speed), among many other applications. The feasibility to create scattering coefficient and wind speed maps over the ocean using the Delay-Doppler Maps (DDMs) has also been analyzed. In this work a case...
The spectral window at L-band (1.400 - 1.427 GHz) is reserved for passive microwave remote sensing. This band is well-suited to retrieve soil moisture and ocean salinity due to emissivity of soil and seawater decreases with moisture and salinity, respectively, affecting microwave radiation of the Earth's surface. Nowadays, there are two space missions devoted to Earth observation with L-band radiometers...
Geostationary interferometric microwave sounder (GIMS), which is developed by National Space Science Center of CAS, will be the main payload on board of FY-4M satellite to monitor and measure internal constitution and precipitation parameters of atmosphere cloud cluster. GIMS is an interferometric aperture synthesis radiometer. Antenna array of GIMS can obtain visibility functions of observation objects...
We introduce a method to determine the gradient between measured physical temperature and true radiating surface temperature of a passive microwave calibration target (load or blackbody). An empirical cooling-curve fit is employed to determine heat-transfer coefficients that then allow commercial finite-element software to solve for the physical temperature at the surface of the target. Only gradients...
This paper presents the comparison of the in-orbit calibrations between the microwave sounders on the National Oceanic and Atmospheric Administration (NOAA) 15, 16, 17, 18 and 19 and FengYun 3A (FY-3A) and FY-3B satellites using the ray-matching method over the South Pole and North Pole study area in 2011. The results show that the in-orbit calibrations of NOAA Advanced Microwave Sounding Unit A (AMSU-A/NOAA)...
In the paper the detectability of a fire by a microwave radiometer is investigated. Simulations of several scenarios and together with outdoor measurement were performed in order to confirm detectability of the fire of specific temperature distributions and dimensions. Various scenarios for fire sensing were numerically modeled and simulated. Real parameters of antenna radiation pattern and radiometer...
The ground testing equipment is essential debugging and testing equipment for microwave remote sensor on satellite. The design and realization methods of ground testing equipment bus interface conversion circuit for FY-3 satellite and HY-2 satellite microwave radiometer and microwave scattermeter are expounded in this paper. FPGA technology, MCU technology and DDS technology are adopted in this ground...
This paper proposes a new technique for hyperspectral band selection from the spectral similarity perspective. Through a newly defined measure for band subset discriminativeness, class-specific important bands are retained which can preserve the spectral similarity of the samples from the same class and narrow down candidate band subset for the following search procedure. Then optimal search is performed...
This paper proposes a new similarity measure to integrate the spectral and spatial-contextual information in the hyperspectral imagery into the manifold learning methods. Including spatial information using the spatial neighbor, the proposed similarity measure is based on the fact that the observation pixels in the hyperspectral imagery are spatially related and relevant information can be extracted...
Dimensionality reduction is often adopted for hyperspectral imagery in advance to improve the efficiency of following processing, such as classification and identification. Affinity propagation (AP), which is a clustering algorithm, has shown the ability to automatically pick out the representative bands from the hyperspectral imagery. Several distance measures have been proposed to construct the...
In this letter, we present a novel approach for spectral-spatial classification in hyperspectral imagery. To this end, after applying principal component analysis (PCA) for dimensionality reduction, we extract the spectral-spatial information by first reorganizing the local image patch with the first d principal components(PCs) into a vector representation, followed by a sorting scheme to make it...
Hyperspectral sensing provides unique capabilities due its intrinsic ability to identify materials. However, like in any other pattern recognition application, system noise and variations in target property (spectral signature in this case), give rise to false alarms while processing. False alarms can also occur if the scene is cluttered with objects made of similar materials. In this study a simple...
A new object-oriented mapping approach is proposed based on nonlinear subspace feature analysis of hyperspectral data. A nonlinear manifold learning approach ISOMAP were utilized to obtain subspace feature representation of hyperspectral remote sensing imagery. Afterwards, the extracted subspace feature images were fed into the object-oriented system. Multiresolution segmentation algorithm was utilized...
We propose CUR methods for hyperspectral unmixing that decompose the data matrix into non-negative endmembers and abundance maps. The endmembers will be selected from a dictionary constructed from the data matrix. Each endmember will coincide with certain columns of the data matrix. By doing this we are assured that the dictionary will be physically meaningful and may be interpreted unambiguously...
Hyperspectral remote sensing is a technique based on the spectroscopy, which contains abundant spectral information besides the spatial information of the images, and overcomes the limitations of the wide-band remote sensing detection. When classifying hyperspectral and multispectral images with the existing algorithms, we use only the spectral information more often. This paper presents an one-class...
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