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Geoscience and Remote Sensing, IEEE Transactions on

Issue 7 • Date July 2004

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Displaying Results 1 - 25 of 33
  • [Front cover]

    Page(s): c1
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  • IEEE Transactions on Geoscience and Remote Sensing publication information

    Page(s): c2
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  • Table of contents

    Page(s): 1353 - 1354
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  • Small-target detection in sea clutter

    Page(s): 1355 - 1361
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (712 KB) |  | HTML iconHTML  

    Sea clutter in marine surveillance radar makes the task of detecting small targets a very challenging problem. In this paper, a set of three signal processing techniques designed to suppress unwanted sea clutter radar echo and achieve target detection with no prior knowledge of the ocean and environmental conditions is presented. These include signal averaging, time-frequency representation, and morphological filtering. Datasets from real marine radar operating in staring mode are used to illustrate the performance of the new approaches. View full abstract»

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  • Focusing bistatic synthetic aperture radar using dip move out

    Page(s): 1362 - 1376
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (816 KB) |  | HTML iconHTML  

    The appearance of new synthetic aperture radar (SAR) acquisition techniques based on opportunity sources enhances interest in bistatic geometries. In seismic data acquisition, each source is currently accompanied by up to 10 000 receivers, and in the last two decades, the bistatic geometry has been carefully studied by scores of authors. Rather then introducing new focusing techniques, within the first-order Born approximation (no multiple reflections), seismic bistatic acquisitions are transformed into monostatic ones using a simple operator named "dip move out" (DMO). In essence, the elliptical locus of the reflectors corresponding to a spike in the bistatic survey is forward modeled as if observed in a monostatic one. The outcome of the model, the so-called smile, is a short operator, slowly time varying but space stationary. To transform a bistatic survey into a monostatic one, it is enough to convolve the initial dataset with this smile. Based on the well-known similarity between seismic and SAR surveys, DMO is first described in its simple geometric understanding and is then used in the SAR case. The same processing that is being used for movement compensation can be applied to the bistatic to monostatic survey transformation. Synthetic examples are also provided. View full abstract»

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  • A small-baseline approach for investigating deformations on full-resolution differential SAR interferograms

    Page(s): 1377 - 1386
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB) |  | HTML iconHTML  

    This paper presents a differential synthetic aperture radar (SAR) interferometry (DIFSAR) approach for investigating deformation phenomena on full-resolution DIFSAR interferograms. In particular, our algorithm extends the capability of the small-baseline subset (SBAS) technique that relies on small-baseline DIFSAR interferograms only and is mainly focused on investigating large-scale deformations with spatial resolutions of about 100×100 m. The proposed technique is implemented by using two different sets of data generated at low (multilook data) and full (single-look data) spatial resolution, respectively. The former is used to identify and estimate, via the conventional SBAS technique, large spatial scale deformation patterns, topographic errors in the available digital elevation model, and possible atmospheric phase artifacts; the latter allows us to detect, on the full-resolution residual phase components, structures highly coherent over time (buildings, rocks, lava, structures, etc.), as well as their height and displacements. In particular, the estimation of the temporal evolution of these local deformations is easily implemented by applying the singular value decomposition technique. The proposed algorithm has been tested with data acquired by the European Remote Sensing satellites relative to the Campania area (Italy) and validated by using geodetic measurements. View full abstract»

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  • Interference from 24-GHz automotive radars to passive microwave earth remote sensing satellites

    Page(s): 1387 - 1398
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (840 KB) |  | HTML iconHTML  

    The automotive industry is currently considering the introduction of short-range radars (SRR) operating near 24 GHz for improving road traffic safety. SSRs are intended to observe the full azimuthal space cover around a vehicle using up to eight sensors. The sensors would operate in an ultrawideband (UWB) mode, occupying 3-5 GHz of bandwidth. Interference from SRR transmitters with passive microwave remote sensing satellites used for weather and climate monitoring could occur as the result of several coupling mechanisms, including direct coupling via the transmit antenna beam and scattering and diffraction of the transmitted signals from leading vehicles, buildings, and other nearby objects. In this study, we estimate the amount of coupling anticipated to occur from SRRs, including the direct and scattered contributions. The calculations are based on bistatic scattering measurements of a typical automobile and ray optical simulations of reflection and propagation in an urban environment. Using these calculations, the maximum allowable SRR transmitted power for interference levels acceptable for meteorological and climatological remote sensing applications are quantified. The study provides criteria for SRR operation with the Earth Exploration Satellite Service on a noninterference basis. View full abstract»

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  • A new high-voltage electric field instrument for studying sprites

    Page(s): 1399 - 1404
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    The high-voltage (HV) electric field detector is a new high-voltage, high-impedance, double Langmuir probe instrument designed for stratospheric electric field measurements. In the Sprite Balloon Campaign 2002-2003, this HV instrument was used to measure electric fields between 100 and 200 V/m associated with lightning discharges, which is nearly an order of magnitude higher than previously reported above 30 km in altitude. This increased range is made possible by the availability of new low-leakage HV operational amplifiers. This is a critical instrument, since a large quasi-DC electric field associated with positive cloud-to-ground lightning is a primary component of most sprite generation mechanisms. The difficulty that exists when making electric field measurements in the high-resistance environment of the stratosphere is presented, and how this difficulty is remedied is described. The HV detector is compared to another electric field instrument, the low-voltage detector, used simultaneously on the Sprite Balloon Campaign to verify the accuracy of the HV probes. Finally, a large field perturbation (Ez≈-101 V/m and Ex≈79 V/m) measured by the HV detector during Flight 1, correlated with nearby +15-kA and +53-kA cloud-to-ground strokes, is presented. View full abstract»

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  • Faraday rotation correction in the polarimetric mode of MIRAS

    Page(s): 1405 - 1410
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    This paper describes a new method to compensate the Faraday rotation in polarimetric radiometric measurements under the assumption that the polarimetric brightness temperature matrix of the target is diagonal. Simulations results of how this method can be used within the Soil Moisture and Ocean Salinity mission and the Microwave Imaging Radiometer with Aperture Synthesis imaging radiometer are presented. View full abstract»

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  • Simultaneous wind and rain retrieval using SeaWinds data

    Page(s): 1411 - 1423
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (888 KB) |  | HTML iconHTML  

    The SeaWinds scatterometers onboard the QuikSCAT and the Advanced Earth Observing Satellite 2 measure ocean winds on a global scale via the relationship between the normalized radar backscattering cross section of the ocean and the vector wind. The current wind retrieval method ignores scattering and attenuation of ocean rain, which alter backscatter measurements and corrupt retrieved winds. Using a simple rain backscatter and attenuation model, two methods of improving wind estimation in the presence of rain are evaluated. First, if no suitable prior knowledge of the rain rate is available, a maximum-likelihood estimation technique is used to simultaneously retrieve the wind velocity and rain rate. Second, when a suitable outside estimate of the rain rate is available, wind retrieval is performed by correcting the wind geophysical model function for the known rain via the rain backscatter model. The new retrieval techniques are evaluated via simulation and validation with data from the National Centers for Environmental Prediction and the Tropical Rainfall Measuring Mission Precipitation Radar. The simultaneous wind/rain estimation method yields most accurate winds in the "sweet spot" of SeaWinds' swath. On the outer-beam edges of the swath, simultaneous wind/rain estimation is not usable. Wind speeds from simultaneous wind/rain retrieval are nearly unbiased for all rain rates and wind speeds, while conventionally retrieved wind speeds become increasingly biased with rain rate. A synoptic example demonstrates that the new method is capable of reducing the rain-induced wind vector error while producing a consistent (yet noisy) estimate of the rain rate. View full abstract»

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  • Assessing the quality of SeaWinds rain measurements

    Page(s): 1424 - 1432
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (552 KB) |  | HTML iconHTML  

    While SeaWinds was designed to measure ocean winds, it can also measure rain over the ocean. SeaWinds on QuikSCAT active measurements of integrated columnar rain rate obtained via simultaneous wind/rain retrieval are evaluated via Monte Carlo simulation and the Crame´r-Rao lower bound on estimate accuracy. Although sufficiently accurate in many conditions, the simultaneous wind/rain retrieval method used with SeaWinds on QuikSCAT data is ill-conditioned for certain wind directions and measurement geometries, sometimes yielding spurious rain rates in zero-rain conditions. To assess the validity of SeaWinds-derived rain rates, a simple empirically based rain thresholding scheme is presented, derived from simulated data. Thresholded QuikSCAT rain rates are compared to Tropical Rainfall Measuring Mission Microwave Imager monthly-averaged data, demonstrating good correlation for monthly-averaged data. View full abstract»

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  • Automatic detection and validity of the sea-ice edge: an application of enhanced-resolution QuikScat/SeaWinds data

    Page(s): 1433 - 1443
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (832 KB) |  | HTML iconHTML  

    Sea-ice edge detection is an essential task at the different national ice services to secure navigation in ice-covered seas. Comparison between the Remund and Long ice mask image from enhanced-resolution QuikScat/SeaWinds (QS) products and the analyzed ice edge from high-resolution RADARSAT synthetic aperture radar has shown that the automatically determined QS ice mask underestimates the Arctic ice extent. QS data was statistically analyzed by colocating the data with ice charts around Greenland and with the National Aeronautics and Space Administration Team's Special Sensor Microwave/Imager (SSM/I) ice concentration algorithm over the whole Arctic region. All variables, i.e., the backscatter in vertical and horizontal polarization, the active polarization ratio (APR) and the daily standard deviation, are sensitive to ice types and are strongly correlated with ice concentration when the relationship is expressed in exponential form. Our study showed that the APR is especially suitable for ice-ocean separation, and a threshold of -0.02 was determined. An ice edge algorithm based on this APR threshold was developed using the other variables with conservative season-dependent thresholds to eliminate additional ocean noise. Also, the history of the ice cover is considered in order to detect single ice fields that are separated from the main Arctic pack ice. Validation with RADARSAT 1 and with the Advanced Very High Resolution Radiometer showed that the new algorithm successfully detects very low ice concentrations of about 10% during the entire year. The validity of the detected ice edge for near-real-time issues is also discussed in relation to the ice motion in the Marginal Ice Zone and the integration time necessary to produce the enhanced-resolution images. The new algorithm improves the automatic global ice edge resolution by a factor of two when compared to SSM/I products and could be used in both model initialization and data assimilation. View full abstract»

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  • Ku-band backscatter from the Cowlitz River: Bragg scattering with and without rain

    Page(s): 1444 - 1449
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (304 KB) |  | HTML iconHTML  

    Ku-band backscatter from the Cowlitz River in southwestern Washington State was measured for incidence angles from 0° to 80°. The measurements were made for light-wind conditions with and without rain. In rain-free conditions, Bragg scattering was the dominant scattering mechanism for both horizontal (HH) and vertical (VV) polarizations out to 75°, beyond which the SNR dropped very low at HH. When a light rain was falling on the river, the cross section increased substantially at moderate incidence angles. Doppler spectra taken during rain showed that VV polarized backscatter is primarily from Bragg scattering from ring waves, while HH polarization scatters from both ring waves and stationary splash products, depending on the incidence angle. From the VV polarized measurements, surface wave height spectrum for ring waves is inferred for light rains. Finally, a change in spectral properties was observed when rain changed to hail. View full abstract»

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  • An analytical approach for the inverse scattering solution of radially inhomogeneous spherical bodies using higher order TE and TM illuminations

    Page(s): 1450 - 1455
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    A novel method for the reconstruction of inhomogeneous permittivity profiles of spherical dielectric objects illuminated by higher order TEmn and TMmn spherical modes is presented. The overall technique is based on the derivation of Riccati-similar nonlinear differential equations in a spherical coordinate system for both TE and TM illuminations as a part of the direct problem formulation. These differential equations are then inverted using a quasi-linear approach to obtain a closed-form expression of the radially varying permittivity profile of spherical objects in terms of a spherical Fourier-Bessel transform of the measured spectral domain reflection coefficient data. To validate the proposed method, several examples with different mode illuminations and with different noise levels are considered for reconstructions. A good agreement between the actual and the reconstructed permittivity profiles even under high noisy conditions shows that our method is not much sensitive to the presence of noise in the reflection coefficient data. View full abstract»

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  • An inverse scattering approach based on the differential E-formulation

    Page(s): 1456 - 1461
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    An inverse scattering technique based on the differential E-formulation in the frequency domain is proposed. The inversion is achieved by minimizing a cost functional, taking into account the discrepancy between measured and estimated field values, while the Helmholtz wave equation is set as constraint. The Fre´chet derivatives of the cost functional with respect to the scatterer properties are derived analytically by means of the calculus of variations. Edge elements are used for the numerical treatment of the problem. View full abstract»

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  • Modeling light scattering at soil surfaces

    Page(s): 1462 - 1471
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    Structures visible on soil profiles contain transport-relevant information. The ultimate goal of this study is to map regions of similar texture on excavated soil profiles. The shape and especially the connectivity of such structures is a first-order approximation for quantifying the transport domains that can be used to predict flow and transport. With this study, we try to understand the spectral information of soil profile images to quantify the spatial arrangement of such structural features. The first and important step is to produce a texture map of the soil profiles from reflectance measurements. Thus, we evaluate reflectance and transmittance spectra measured on small areas of soil surfaces. Reflectance and transmittance depend on particle size. Measurements and simulations show that the influence of texture on reflectance is measurable but small. In this study, we describe first light scattering by idealized particles. They shall represent natural soil particles. We calculate the light absorption and the directional distribution of the scattered light. Second, we use these properties to describe the radiative transfer of visible light and infrared radiation using a four-flux model. The four-flux model combined with the idealized particle model yields a model with which we can calculate the relation between average particle size and reflectance. To test our radiative transfer model, the reflectance and transmittance of three soil materials were measured. The three soil materials differ in color. Each material was sieved into seven fractions to prepare samples of the same material but different texture. Fitting the complex refractive indexes to the measured spectra indicates that these materials can be differentiated and classified according to their light absorption properties. View full abstract»

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  • Absolute calibration of VEGETATION derived from an interband method based on the Sun glint over ocean

    Page(s): 1472 - 1481
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    Absolute radiometric calibration is one of the main elements that contribute to the quality of measurements obtained with optical remote sensing instruments, but maintaining a good calibration accuracy during the whole life of an instrument is a difficult task. Since the sensitivity of an instrument generally changes after launch and degrades with time, many sensors have been equipped with onboard calibration devices. But these devices being not perfectly reliable, independent calibration methods based on natural targets are necessary to validate the results. The Sun glint calibration method is an interband calibration method that uses the specular reflection of the Sun on the ocean surface to transfer the absolute calibration of one reference spectral band to other spectral bands, from visible to short wave infrared wavelengths. Despite the drawback of relying on the absolute calibration of a reference spectral band, this method is one of the rare methods that can provide accurate calibration results for near-infrared spectral bands up to 1650 nm, without requiring costly in situ measurements simultaneously to the satellite overpass. This paper details the Sun glint calibration method and its error budget, and gives the results obtained with the VEGETATION instrument that was recently launched onboard the Systeme Pour l'Observation de la Terre 5 (SPOT-5) satellite. These results compare very well with the results of other calibration methods. View full abstract»

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  • Use of the scanning multichannel microwave radiometer (SMMR) to retrieve soil moisture and surface temperature over the central United States

    Page(s): 1482 - 1494
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    The 6.6-, 10.7-, and 18-GHz data from the Scanning Multichannel Microwave Radiometer (SMMR) for 1979, 1980, and 1982 have been used to derive soil moisture and surface temperature for the south central United States. The 1979 data have been used to calibrate the radiative transfer model parameters, and the 1980 and 1982 data were used to derive soil moisture and surface temperature that have been compared with the corresponding values from the National Centers for Environmental Prediction (NCEP) reanalyses model outputs. These comparisons have shown that SMMR is able to qualitatively predict the seasonal cycle of land surface hydrological variability, and this information can be used for studies involving land-atmosphere interaction and hydrology. This study is of particular importance with the presence of both the Aqua satellite and the Advanced Earth Observing Satellite II that carry onboard the Advanced Microwave Scanning Radiometer (AMSR), which has channels similar to the SMMR, but with better spatial resolution. The results of this study will help us to plan for AMSR retrievals of soil moisture and surface temperature. View full abstract»

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  • Impact of horizontal and vertical heterogeneities on retrievals using multiangle microwave brightness temperature data

    Page(s): 1495 - 1501
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (544 KB) |  | HTML iconHTML  

    This paper investigates the impact of heterogeneity at the land surface on geophysical parameters retrieved from multiangle microwave brightness temperature data, such as would be obtained from the Soil Moisture and Ocean Salinity (SMOS) mission. Synthetic brightness temperature data were created using the Common Land (land surface) Model, coupled with a microwave emission model and set within the framework of the North American Land Data Assimilation System (NLDAS). Soil moisture, vegetation optical depth, and effective physical temperature were retrieved using a multiobjective calibration routine similar to the proposed SMOS retrieval algorithm for a typical on-axis range of look angles. The impact of heterogeneity both in the near-surface profiles of soil moisture and temperature and in the land cover on the accuracy of the retrievals was examined. There are significant errors in the retrieved parameters over regions with steep gradients in the near-surface soil moisture profile. These errors are approximately proportional to the difference in the soil water content between the top (at 0.7 cm) and second layer (at 2.7 cm) of the land surface model. The errors resulting from heterogeneity in the land cover are smaller and increase nonlinearly with increasing land-surface heterogeneity (represented by the standard deviation of the optical depth within the pixel). The most likely use of retrieved soil moisture is through assimilation into an LDAS for improved initiation of weather and climate models. Given that information on the soil moisture profile is already available within the LDAS, the error in the retrieved soil moisture as a result of the near-surface profile can be corrected for. The potential errors as a result of land-surface heterogeneity can also be assessed for use in the assimilation process. View full abstract»

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  • Application of the biorthogonal multiresolution time-domain method to the analysis of elastic-wave interactions with buried targets

    Page(s): 1502 - 1511
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    The biorthogonal multiresolution time-domain (Bi-MRTD) method is introduced for the analysis of elastic-wave interaction with buried targets. We provide a detailed discussion on implementation of the perfectly matched layer and on treatment of the interface between two different materials. The algorithm has also been parallelized by the use of the message-passing interface. The numerical results show that numerical dispersion can be significantly improved by using biorthogonal wavelets as bases, as compared to the conventional pulse expansion employed in the finite-difference time-domain (FDTD) method. We demonstrate that with comparison to the second-order FDTD, the Bi-MRTD yields significant CPU time and memory savings for large problems, for a fixed level of accuracy. View full abstract»

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  • The PROBA/CHRIS mission: a low-cost smallsat for hyperspectral multiangle observations of the Earth surface and atmosphere

    Page(s): 1512 - 1520
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (448 KB) |  | HTML iconHTML  

    The European Space Agency's Project for On-Board Autonomy is intended to demonstrate a range of innovations in the design, construction, and operation of small satellites. It carries a number of scientific instruments, the most advanced of which is the Compact High-Resolution Imaging Spectrometer. A typical nadir image is 13 km ×13 km in size and has 18 narrow spectral channels at 17-m spatial resolution. When operated at 34-m spatial resolution, the instrument can capture data in 62, almost contiguous, spectral channels. The platform is highly manoeuvrable: along-track pointing allows a given site to be imaged five times during a single overpass, while across-track pointing ensures that the revisit time for a site of interest is less than a week. This unique combination of spectral and angular sampling provides a rich source of data with which to study environmental processes in the atmosphere and at the Earth's surface. View full abstract»

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  • A new algorithm for temperature and spectral emissivity retrieval over active fires in the TIR spectral range

    Page(s): 1521 - 1529
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB) |  | HTML iconHTML  

    The problem of temperature and spectral emissivity assessment from hyperspectral remotely sensed data is discussed with reference to monitoring of active fires and hot targets. A new algorithm, called similar pixel addition, was developed, which allows us to retrieve the temperature of burning areas by employing spectral data collected at thermal infrared (TIR) wavelengths. The new algorithm resolves the uncertainty connected with temperature-emissivity separation assuming a slow spatial variation of emissivity, hence reducing the number of unknowns involved in the inversion of a couple of similar pixels at once. Performance of this procedure is thoroughly discussed and compared with results from two other algorithms operating in the TIR and shortwave infrared spectral ranges. This paper shows results obtained applying the new algorithm to hyperspectral images gathered by the Multispectral Infrared and Visible Imaging Spectrometer in Northern Italy (Alps) over a natural fire that broke out in July 1999. This paper is completed with a theoretical discussion of the involved topics. View full abstract»

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  • Robust support vector method for hyperspectral data classification and knowledge discovery

    Page(s): 1530 - 1542
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    We propose the use of support vector machines (SVMs) for automatic hyperspectral data classification and knowledge discovery. In the first stage of the study, we use SVMs for crop classification and analyze their performance in terms of efficiency and robustness, as compared to extensively used neural and fuzzy methods. Efficiency is assessed by evaluating accuracy and statistical differences in several scenes. Robustness is analyzed in terms of: (1) suitability to working conditions when a feature selection stage is not possible and (2) performance when different levels of Gaussian noise are introduced at their inputs. In the second stage of this work, we analyze the distribution of the support vectors (SVs) and perform sensitivity analysis on the best classifier in order to analyze the significance of the input spectral bands. For classification purposes, six hyperspectral images acquired with the 128-band HyMAP spectrometer during the DAISEX-1999 campaign are used. Six crop classes were labeled for each image. A reduced set of labeled samples is used to train the models, and the entire images are used to assess their performance. Several conclusions are drawn: (1) SVMs yield better outcomes than neural networks regarding accuracy, simplicity, and robustness; (2) training neural and neurofuzzy models is unfeasible when working with high-dimensional input spaces and great amounts of training data; (3) SVMs perform similarly for different training subsets with varying input dimension, which indicates that noisy bands are successfully detected; and (4) a valuable ranking of bands through sensitivity analysis is achieved. View full abstract»

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  • Texture feature analysis using a gauss-Markov model in hyperspectral image classification

    Page(s): 1543 - 1551
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (536 KB) |  | HTML iconHTML  

    Texture analysis has been widely investigated in the monospectral and multispectral imagery domains. At the same time, new image sensors with a large number of bands (more than ten) have been designed. They are able to provide images with both fine spectral and spatial sampling, and are called hyperspectral images. The aim of this work is to perform a joint texture analysis in both discrete spaces. To achieve this goal, we propose a probabilistic vector texture model, using a Gauss-Markov random field (MRF). The MRF parameters allow the characterization of different hyperspectral textures. A possible application of this work is the classification of urban areas. These areas are not well characterized by radiometry alone, and so we use the MRF parameters as new features in a maximum-likelihood classification algorithm. The results obtained on Airborne Visible/Infrared Imaging Spectrometer hyperspectral images demonstrate that a better classification is achieved when texture information is included in the analysis. View full abstract»

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  • Distance metrics and band selection in hyperspectral processing with applications to material identification and spectral libraries

    Page(s): 1552 - 1565
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (568 KB) |  | HTML iconHTML  

    At the core of most hyperspectral processing algorithms are distance metrics that compare two spectra and return a scalar value based on some notion of similarity. The two most common distance metrics in hyperspectral processing are the spectral angle mapper (SAM) and the Euclidean minimum distance (EMD), and each metric possesses distinct mathematical and physical properties. In this paper, we enumerate the characteristics of both metrics, and, based on an exact decomposition of SAM, we derive a technique called band add-on (BAO) that iteratively selects bands to increase the angular separation between two spectra. Unlike other feature selection algorithms, BAO exploits a mathematical decomposition of SAM to incrementally add bands. We extend BAO to the more practical problem of increasing the angular separability between two classes of spectra. This scenario parallels the material identification problem where quite often only a small number (<10) of ground-truth measurements are collected for each material class, and statistical classification methods are inapplicable. Two algorithms for selecting bands and class templates are presented to increase the angular separation between two classes. The techniques are compared with several other metric-based approaches in binary discrimination tests with real data. The results demonstrate that band selection can improve the discrimination of very similar targets, while using only a fraction of the available spectral bands. View full abstract»

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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