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Geoscience and Remote Sensing, IEEE Transactions on

Issue 2 • Date Feb 2001

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Displaying Results 1 - 25 of 27
  • Correction to: "Novel diffraction tomographic algorithm for imaging two-dimensional targets buried under a lossy earth"

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    The paper by T. J. Cui and W. C. Chew, IEEE Trans. Geosci. Remote Sensing, vol. 38, p.2033-41 (2000) is corrected. The authors, in that paper, defined the branch cut of K/sub ay/ and k/sub by/ in an equation (7) as Re(k/sub ay/,/sub by/)/spl ges/0 and Im(k/sub ay/,/sub by/)/spl ges/0 to make the Sommerfeld-like integral in another equation(5) satisfy the radiation condition. In the inverse-Fourier expression of yet another equation (24), however, they had to choose the branch cut of k/sub by/ in a different way, where Re(k/sub by/)/spl ges/O and Im(k/sub ay/,/sub by/)/spl les/, so that the integral in this equation can be convergent. Hence, the k/sub by/ in equation (27) must be set in different branch cuts. Although such a procedure gave correct reconstruction results, the mathematical interpretation was confusing. In this correspondence, the authors now modify the mathematical interpretation so that it is clear and easily understood. View full abstract»

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  • Development of target null theory

    Page(s): 330 - 338
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    In a co- or cross-polarized channel, the polarization states of the transmitting and receiving antennas are the same or orthogonal, and the corresponding target nulls (i.e., the co-pol nulls or x-pol nulls) are defined as the polarization states of the transmitting antenna such that the received power equals zero. However, no systematic studies have been carried out to solve the problem of the corresponding target nulls if the polarization states of the transmitting and receiving antennas are independent. In this paper, the target null theory is extended to the case of two independent polarization states. For two arbitrary independent symmetric scattering matrices, it is proved that there exists only one pair of polarization states such that both of the received powers equal zero. This polarization states' pair is called the co-null of the two targets, which can easily be obtained by solving an eigenvalue problem. Based on this concept and algebraic theory, the concept of the co-null space is introduced for the symmetric scattering matrix case, and many important results are presented, e.g., the relations between the co-null and the co-pol/x-pol nulls, the properties of the co-null space, and the relation between the co-null and target decomposition. Finally, the co-null for the asymmetric scattering matrix case is studied. The concepts of the mono-co-null space and the bi-co-null space are introduced, and the relations between both spaces are presented View full abstract»

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  • Airborne measurements of forest and agricultural land surface emissivity at millimeter wavelengths

    Page(s): 393 - 400
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    Passive microwave radiometers have been operated on an aircraft over the an area of Sweden, near Uppsala in September 1995 and March 1997 as part of the Northern Processes Experiment (NOPEX). Their measurements have allowed the calculation of the emissivity of boreal forest and agricultural land surfaces at 24, 50, 89, and 157 GHz over a range of incidence angles and polarizations. These results show consistent differences between dense forestry, where the emissivity is close to 1 and open land, where it is approximately 0.96. These differences are examined and a model is presented to parameterize these surfaces by use of a Debye-like effective permittivity and Fresnel's reflection coefficients. This will allow retrievals of atmospheric temperature and humidity profiles to be made by satellite microwave sounders, such as the advanced microwave sounding unit (AMSU) over similar land surfaces View full abstract»

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  • The hybrid extended Born approximation and CG-FFT method for electromagnetic induction problems

    Page(s): 347 - 355
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    The authors propose the hybridization of the extended Born approximation (EBA) with the conjugate-gradient fast Fourier transform (CG-FFT) method to improve the efficiency of numerical solution of electromagnetic induction problems. This combination improves the solution efficiency in two ways. First, using the FFT in the extended Born approximation decreases the computational cost of the conventional EBA method from O(N2) to O(N log2 N) arithmetic operations, where N is the number of unknowns in the problem. This approach, referred to as the FFT-EBA method, applies to problems with a fairly large contrast. Secondly, using the EBA as a partial preconditioner for the CG-FFT method increases the convergence speed of the conventional CG-FFT method. This second approach, referred to as the EBA-CGFFT method, is in principle applicable to all problems with a homogeneous background, but is particularly efficient for problems with a higher contrast. Numerical experiments suggest that the combination of these two methods is more accurate and more efficient for electromagnetic induction problems View full abstract»

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  • Embedded wavelet-based coding of three-dimensional oceanographic images with land masses

    Page(s): 284 - 290
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    We describe the wavelets around land masses (WAVAL) system for the embedded coding of three-dimensional (3-D) oceanographic images. These images differ from those arising in other applications in that valid data exists only at grid points corresponding to sea. Grid points that cover land or lie beyond the bathymetry have no associated data. For these images, the WAVAL system employs a 3-D lifting wavelet transform tailored specifically to the potentially sparse nature of the data by processing only the valid sea data points between land masses. We introduce successive-approximation runlength (SARL) coding, an embedded-coding procedure that adds successive-approximation properties to the well known stack-run (SR) algorithm. SARL is employed to code wavelet coefficients resulting from the 3-D transform in the WAVAL system. However, it is a general technique applicable to other coding tasks in which embedded coding is desired but for which zerotree techniques are impractical. Experimental results show that the WAVAL system achieves substantial improvement in rate-distortion performance over the technique currently used by the US Navy for compression of oceanographic imagery View full abstract»

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  • Unsupervised retraining of a maximum likelihood classifier for the analysis of multitemporal remote sensing images

    Page(s): 456 - 460
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    An unsupervised retraining technique for a maximum likelihood (ML) classifier is presented. The proposed technique allows the classifier's parameters, obtained by supervised learning on a specific image, to be updated in a totally unsupervised way on the basis of the distribution of a new image to be classified. This enables the classifier to provide a high accuracy for the new image even when the corresponding training set is not available View full abstract»

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  • Development of a technique to assess snow-cover mapping errors from space

    Page(s): 432 - 438
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    Following the December 18, 1999, launch of the Earth Observing System (EOS) Terra satellite, daily snow-cover mapping is performed automatically at a spatial resolution of 500 m, cloud-cover permitting, using moderate resolution imaging spectroradiometer (MODIS) data. This paper describes a technique for calculating global-scale snow mapping errors and provides estimates of Northern Hemisphere snow mapping errors based on prototype MODIS snow mapping algorithms. Field studies demonstrate that under cloud-free conditions, when snow cover is complete, snow mapping errors are small (<1%) in all land covers studied except forests, where errors are often greater and more variable. Thus, the accuracy of Northern Hemisphere snow-cover maps is largely determined by percent of forest cover north of the snowline. From the 17-class International Geosphere-Biosphere Program (IGBP) land-cover maps of North America and Eurasia, the authors classify the Northern Hemisphere into seven land-cover classes and water. Estimated snow mapping errors in each of the land-cover classes are extrapolated to the entire Northern Hemisphere for areas north of the average continental snowline for each month. The resulting average monthly errors are expected to vary, ranging from about 5-10%, with the larger errors occurring during the months when snow covers the boreal forest in the Northern Hemisphere. As determined using prototype MODIS data, the annual average estimated error of the future Northern Hemisphere snow-cover maps is approximately 8% in the absence of cloud cover, assuming complete snow cover. Preliminary error estimates will be refined after MODIS data have been available for about one year View full abstract»

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  • A weighted least squares solution for space intersection of spaceborne stereo SAR data

    Page(s): 233 - 240
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    The use of stereoscopic SAR images offers an alternative to interferometric SAR for the generation of digital elevation models (DEMs). The stereo radargrammetric method is robust and can generate DEMs of sufficient accuracy to geocode SAR images. Previous work has shown that ground coordinates with accuracy of four times the resolution cell can be obtained from ERS data without using any ground control points (GCPs), where the high accuracy of the orbit and satellite position of the order of metres introduce insignificant errors into the intersection procedure. The orbit data for RADARSAT is not as accurate as that for ERS, and the perpendicular relationship between the resultant velocity vector and the resultant range vector is uncertain in terms of image geometry. Hence, it is necessary to refine the method to allow for possible errors. This paper introduces a weighted space intersection algorithm based on an analysis of the predicted errors. A radargrammetric error model for observation errors is also formulated to predict the accuracy of the algorithm. The revised method can be used without any GCPs, but this can lead to systematic errors due to less accurate orbit data, and it has been found that the use of two GCPs provides a reasonable solution. The method is insensitive to the spatial distribution of GCPs, which is often critical in traditional methods. The error statistics of the results generated from 32 independent check points, distributed through the entire SAR image, approach the predicted errors and give positional accuracy of 38 m in three dimensions View full abstract»

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  • Discrimination of UXO in soil using broadband polarimetric GPR backscatter

    Page(s): 356 - 367
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    Polarimetric analysis of ground penetrating radar (GPR) backscatter offers a new means of discriminating subsurface metallic target shapes from one another. Such discrimination is urgently needed to distinguish buried unexploded ordnance (UXO) from other subsurface objects. To illuminate the underlying phenomenology of scattering from objects enveloped in soil, three-dimensional (3D) simulations are performed over a broad frequency band, characteristic of new low frequency GPRs. For moist soil, this means that the subsurface wavelength may range from a fraction of the target size to an order of magnitude larger With a transmitting antenna representation that produces typical subsurface GPR beam features, combined effects of positional, orientation, and frequency diversity are investigated. Despite long wavelengths, results show distinctive features in reflections obtained from contrasting example target shapes. Full polarimetric analysis suggests the capability for inferring the length of elongated targets, aspect ratio and rotational symmetry, and gross shape along the axis for either elongated or flattened bodies of revolution in problematical orientations View full abstract»

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  • Thermal emission from a layered medium bounded by a slightly rough interface

    Page(s): 368 - 378
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    The small perturbation method (SPM) is applied to study thermal emission from a layered medium bounded by a slightly rough interface. Brightness temperatures are calculated to second order in surface height, including both specular reflection coefficient corrections and incoherent Bragg scatter terms. Unlike the homogeneous medium case, in which the SPM applied for emission predictions produces an expansion in surface slope, the theory remains a small height expansion, and convergence of the series is shown to depend on properties of the layered medium. Results from this theory can be applied in studies of soil moisture, sea ice, or sea surface remote sensing and buried object detection with microwave radiometers View full abstract»

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  • Segmentation and classification of vegetated areas using polarimetric SAR image data

    Page(s): 321 - 329
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    Classification of radar images based on the information provided by individual pixels cannot generally produce satisfactory results due to speckle. The classification based on area analysis is therefore expected to be more accurate, as a uniform area, which usually consists of multipixels, provides reliable measurement statistics and texture characteristics. However, the area analysis requires partitions of uniform areas to be performed first. In this paper, an approach to the classification of radar images is developed based on two steps. First an image is partitioned into uniform areas (segments), and then these segments are classified. Both segmentation and classification are achieved by using the Gaussian Markov random field model. Test images are classified to demonstrate the method View full abstract»

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  • Tomography of the lower troposphere using a small dense network of GPS receivers

    Page(s): 439 - 447
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    The application of tomographic techniques to the troposphere with GPS signals was demonstrated in previous work using data from the Kilauea permanent network, Hawaii. Local orography of the network considered there, however, played a key role in the resolution capabilities of the technique. The authors explore the possibilities of tomographic reconstruction of the four-dimensional (4D) structure of water vapor using a very small network of global positioning satellite (GPS) receivers with virtually no height differences between the stations. The analyzed campaign consisted of seven GPS receivers located at the Onsala Space Observatory, Onsala, Sweden, and was carried out in August 1998. Traditional meteorological data sources and tools such as the numerical weather model NCAR Mesoscale Model (MM5), satellite data from the National Oceanic and Atmospheric Administration (NOAA), Washington, DC, and data and analysis from the European Center for Medium-Range Weather Forecasting (ECMWF), Reading, UK, have been used to evaluate the results. A good agreement is found between GPS tomography and classical methods, even in meteorological situations with complex vertical structure of water vapor View full abstract»

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  • Amazon floodplain water level changes measured with interferometric SIR-C radar

    Page(s): 423 - 431
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    The authors find that interferometric processing of repeat-pass L-HH-band shuttle imaging radar (SIR-C) data reveals centimeter-scale changes in the elevations of water surfaces within flooded vegetation. Because radar pulses reflect specularly from the water surface, interferometric observations of open water are incoherent. However, within flooded forests and inundated shrubs, the L-band radar pulse penetrates the vegetation canopy and follows a double-bounce travel path that includes the water and vegetation-trunk surfaces. In these environments, the returned radar energy and associated phase coherence are both stronger than the surrounding nonflooded terrain, permitting determination of the interferometric phase. Phase errors related to atmospheric water vapor are usually longer in wavelength and spatially distinct from phase signatures related to stage changes in tributaries and floodplain lakes. The interferometrically measured stage decreases match gauge data, providing further verification. Water level changes across 150 m to 2.75 km-wide water bodies containing inundated vegetation can be reliably measured. The authors' results suggest that if future interferometric L-HH-band SAR missions are implemented with short temporal baselines, it is possible to measure the hydrologic response of wetlands and inundated floodplains to changes in mainstem water level View full abstract»

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  • An improved calibration technique for free-space measurement of complex permittivity

    Page(s): 453 - 455
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    A calibration technique for free-space measurement of the permittivity and conductivity has been developed, taking account of antenna-medium coupling. Thus, the accuracy is improved compared to previously used calibration. Two examples are given to illustrate this improvement View full abstract»

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  • Dual-beam interferometry for ocean surface current vector mapping

    Page(s): 401 - 414
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    The recent use of along-track interferometry (ATI) in synthetic aperture radar (SAR) has shown promise for synoptic measurement of ocean surface currents. ATI-SARs have been used to estimate wave fields, currents, and current features. This paper describes and analyzes a dual-beam along-track interferometer to provide spatially resolved vector surface velocity estimates with a single pass of an aircraft. The design employs a pair of interferometer beams, one squinted forward and one squinted aft. Each interferometric phase is sensitive to the component of surface Doppler velocity in the direction of the beam. Therefore, a proper combination of these measurements provides a vector surface velocity estimate in one pass of the aircraft. The authors find that precise measurements dictate widely spaced beams and that the spatial resolution for the squinted SAR is essentially identical to the sidelooking case. Practical instrument design issues are discussed, and an airborne system currently in development is described. Through computer simulation, they observe the azimuthal displacement of interferometric phases by moving surfaces identical to those of conventional SAR and find that such displacement can bias the estimated surface velocity View full abstract»

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  • Analysis of topographic decorrelation in SAR interferometry using ratio coherence imagery

    Page(s): 223 - 232
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    Topographic decorrelation due to the local surface slope has been an obstacle to interferometric synthetic aperture radar (InSAR) applications. A modified spatial decorrelation function is derived as a function of the baseline and topography. This function explains the origin of the total topographic decorrelation phenomenon on the slopes directly facing radar illumination and layover, which may mislead InSAR coherence image interpretation. The authors define critical terrain slope (or critical incidence angle) as the angle for which two SAR signals completely decorrelate regardless of surface stability. It is found that the width of the critical terrain slope increases with the increase of the component of the baseline perpendicular to the radar look direction. A new analytical method, the ratio coherence imagery, is then introduced to highlight total topographic decorrelation against the temporal decorrelation features. The applications of this methodology are demonstrated in selected locations in the Sahara Desert, Algeria, and Almerı´a, Spain, using ERS-1 and ERS-2 SAR data View full abstract»

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  • A new approach for the morphological segmentation of high-resolution satellite imagery

    Page(s): 309 - 320
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    A new segmentation method based on the morphological characteristic of connected components in images is proposed. Theoretical definitions of morphological leveling and morphological spectrum are used in the formal definition of a morphological characteristic. In multiscale segmentation, this characteristic is formalized through the derivative of the morphological profile. Multiscale segmentation is particularly well suited for complex image scenes such as aerial or fine resolution satellite images, where very thin, enveloped and/or nested regions must be retained. The proposed method performs well in the presence of both low radiometric contrast and relatively low spatial resolution. Those factors may produce a textural effect, a border effect, and ambiguity in the object/background distinction. Segmentation examples for satellite images are given View full abstract»

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  • Theoretical study on two-dimensional Gaussian rough sea surface emission and reflection in the infrared frequencies with shadowing effect

    Page(s): 379 - 392
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    The emission and reflection properties of a two-dimensional (2D) Gaussian rough sea surface are investigated. The emissivity and reflectivity study is of importance for accurate measurement of the temperature distribution of a wind-roughened water surface by infrared thermal imaging. The radius of curvature of the capillary waves being much larger than the wavelength involves the fact that their statistical model is based on the first order geometrical-optics method. In this paper, the first order geometrical optics approximation is considered because the higher order approximations can be neglected compared to the first order approximations. Indeed the total reflected electromagnetic field is damped by the multiple reflections on the surface. They introduce the 2D shadowing function, and the observed surface length in the azimuthal direction with respect to the wind direction. Their emissivity and reflectivity model is obtained from recent works. In order to use the 1D (1D) shadowing function, assume that the average slope of the surface is smaller than unity. Assuming an infinite observed surface length as determines only the emissivity with the 2D shadowing function. Applying their emissivity and reflectivity model, the relation determining the apparent ocean surface temperature is given, in the considered wavelength band, according to the following parameters: wind speed, wavelength, polarization, intrinsic surface temperature, atmospheric transmission coefficient as evaluated by the Taylor and Larmor model, receiver location, and the camera field of view View full abstract»

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  • Three-dimensional effects in the remote sensing of surface albedo

    Page(s): 254 - 263
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    Most of contemporary analysis of satellite data is based on the classical Chandrasekhar's formula for the mean radiance, which is valid only when the surface is infinite and uniform. Over an inhomogeneous surface, the measured radiance will also contain two variational terms describing the direct and diffuse atmospheric transmission of the solar radiation reflected from spatial variations of surface reflectance. Calculation of the diffuse transmission requires knowledge of the atmospheric point-spread function (PSF) or its Fourier transform (FT) optical transfer function (OTF), which is a solution of the 3D radiative transfer problem. Using a method of spherical harmonics, we have previously obtained a rigorous solution for a 2D problem, where surface albedo varies only in one of the coordinate axes. It allows us to precisely model radiance fields over arbitrarily nonhomogeneous Lambertian “striped” surfaces. The simplest surface of this type consists of a dark and a bright homogeneous half-planes. The radiance distribution for this surface model was well studied in the past at high sensor resolution in the nadir direction. In reality, land surface exhibits a broad range of spatial variations, and data available to the land remote sensing community have resolution from tens of meters to several kilometers, often at varying zenith view angles. A study of the 3D effects in these realistic conditions and assessments of the accuracy of atmospheric corrections based on a 1D radiative transfer theory are the main objectives of this work. The conclusions of this study can be summarized as follows. 3-D effects are the major source of albedo errors at high spatial resolution. The errors incurred may be as high as 0.04-0.06 in the near-IR and 0.01-0.04 in the visible range of the spectrum. At a medium resolution of 1 km, these errors are relatively small (0.005-0.02) and are comparable to other sources of errors, such as uncertainties in knowledge of aerosol scattering properties and of bidirectional reflectance in each pixel. However, most of the other errors have a random nature, while 3-D effects are systematic. They always increase the apparent reflectance of the dark targets and decrease the signal from the bright targets. As such, 3-D effects become important even at medium resolution, especially for off-nadir observations. Although our analysis was limited to l-D Lambertian surfaces, the results presented here are general enough to make quantitative conclusions in this still poorly studied but very important area View full abstract»

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  • Angular and seasonal variation of spectral surface reflectance ratios: implications for the remote sensing of aerosol over land

    Page(s): 275 - 283
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    We obtain valuable information on the angular and seasonal variability of surface reflectance using a hand-held spectrometer from a light aircraft. The data is used to test a procedure that allows us to estimate visible surface reflectance from the longer wavelength 2.1 μm channel (mid-IR). Estimating or avoiding surface reflectance in the visible is a vital first step in most algorithms that retrieve aerosol optical thickness over land targets. The data indicate that specular reflection found when viewing targets from the forward direction can severely corrupt the relationships between the visible and 2.1 μm reflectance that were derived from nadir data. There is a month by month variation in the ratios between the visible and the mid-IR, weakly correlated to the Normalized Difference Vegetation Index (NDVI). If specular reflection is not avoided, the errors resulting from estimating surface reflectance from the mid-IR exceed the acceptable limit of Δρ~0.01 in roughly 40% of the cases, using the current algorithm. This is reduced to 25% of the cases if specular reflection is avoided View full abstract»

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  • Pixel classification using variable string genetic algorithms with chromosome differentiation

    Page(s): 303 - 308
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    The concept of chromosome differentiation, commonly witnessed in nature as male and female sexes, is incorporated in genetic algorithms with variable length strings for designing a nonparametric classification methodology. Its significance in partitioning different landcover regions from satellite images, having complex/overlapping class boundaries, is demonstrated. The classifier is able to evolve automatically the appropriate number of hyperplanes efficiently for modeling any kind of class boundaries optimally. Merits of the system over the related ones are established through the use of several quantitative measure View full abstract»

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  • Post-launch calibration of the TRMM microwave imager

    Page(s): 415 - 422
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    Three post-launch calibration methods are used to examine the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) on-orbit performance. The first method is a statistical analysis of TMI ocean observations that reveals a systematic along-scan error. The second method is an intercomparison of TMI and SSM/I observations that shows a warm bias in TMI. The last method is an analysis of TMI observations taken during TRMMs deep-space maneuver. These deep-space observations confirm both the along-scan error found from method 1 and the warm bias found from method 2. The along-scan error exhibits distinctive features having amplitudes near 1 K. The warm bias, which is related to the scene temperature, can be as large are 5 K for ocean measurements. The physical explanation of a slightly emissive main reflector is proposed to explain the calibration errors View full abstract»

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  • Comparison of modeled and measured second azimuthal harmonics of ocean surface brightness temperatures

    Page(s): 448 - 452
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    Second azimuthal harmonics of ocean surface brightness temperatures predicted by the second order small slope approximation (SSA) are compared to an empirical model based on WindRAD experiments performed by the Jet Propulsion Laboratory (JPL), Pasadena, CA. SSA predictions are illustrated for three differing models of the ocean surface directional spectrum, and results as a function of wind speed are shown to be in reasonable agreement with the WindRAD model at 19.35 and 37 GHz and at polar observation angles of 45°, 55°, and 65°. None of the three spectral models, however, completely matches all the trends of the empirical data. A slight modification to one of the spectra is demonstrated to yield an improved agreement View full abstract»

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  • The role of canopy structure in the spectral variation of transmission and absorption of solar radiation in vegetation canopies

    Page(s): 241 - 253
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    This paper presents empirical and theoretical analyses of spectral hemispherical reflectances and transmittances of individual leaves and the entire canopy sampled at two sites representative of equatorial rainforests and temperate coniferous forests. The empirical analysis indicates that some simple algebraic combinations of leaf and canopy spectral transmittances and reflectances eliminate their dependencies on wavelength through the specification of two canopy-specific wavelength-independent variables. These variables and leaf optical properties govern the energy conservation in vegetation canopies at any given wavelength of the solar spectrum. The presented theoretical development indicates these canopy-specific wavelength-independent variables characterize the capacity of the canopy to intercept and transmit solar radiation under two extreme situations, namely, when individual leaves 1) are completely absorptive and 2) totally reflect and/or transmit the incident radiation. The interactions of photons with the canopy at red and near-infrared (IR) spectral bands approximate these extreme situations well. One can treat the vegetation canopy as a dynamical system and the canopy spectral interception and transmission as dynamical variables. The system has two independent states: canopies with totally absorbing and totally scattering leaves. Intermediate states are a superposition of these pure states. Such an interpretation provides powerful means to accurately specify changes in canopy structure both from ground-based measurements and remotely sensed data. This concept underlies the operational algorithm of global leaf area index (LAI), and the fraction of photosynthetically active radiation absorbed by vegetation developed for the moderate resolution imaging spectroradiometer (MODIS) and multiangle imaging spectroradiometer (MISR) instruments of the Earth Observing System (EOS) Terra mission View full abstract»

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  • Inverse scattering of two-dimensional dielectric objects buried in a lossy earth using the distorted Born iterative method

    Page(s): 339 - 346
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    An efficient inverse-scattering algorithm is developed to reconstruct both the permittivity and conductivity profiles of two-dimensional (2D) dielectric objects buried in a lossy earth using the distorted Born iterative method (DBIM). In this algorithm, the measurement data are collected on (or over) the air-earth interface for multiple transmitter and receiver locations at single frequency. The nonlinearity due to the multiple scattering of pixels to pixels, and pixels to the air-earth interface has been taken into account in the iterative minimization scheme. At each iteration, a conjugate gradient (CG) method is chosen to solve the linearized problem, which takes the calling number of the forward solver to a minimum. To reduce the CPU time, the forward solver for buried dielectric objects is implemented by the CG method and fast Fourier transform (FFT). Numerous numerical examples are given to show the convergence, stability, and error tolerance of the algorithm View full abstract»

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Aims & Scope

 

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING (TGRS) is a monthly publication that focuses on the theory, concepts, and techniques of science and engineering as applied to sensing the land, oceans, atmosphere, and space; and the processing, interpretation, and dissemination of this information.

 

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Meet Our Editors

Editor-in-Chief
Antonio J. Plaza
University of Extremadura