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Geoscience and Remote Sensing, IEEE Transactions on

Issue 9 • Date Sept. 2006

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Displaying Results 1 - 25 of 36
  • [Front cover]

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

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  • Table of contents

    Page(s): 2321 - 2322
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  • SAR Sensor Trajectory Deviations: Fourier Domain Formulation and Extended Scene Simulation of Raw Signal

    Page(s): 2323 - 2334
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (313 KB) |  | HTML iconHTML  

    Synthetic aperture radar (SAR) raw signal simulation is a useful tool for SAR system design, mission planning, processing algorithm testing, and inversion algorithm design. A two-dimensional (2-D) Fourier domain SAR raw signal simulator, exploiting the efficiency of fast Fourier transform algorithms, has been presented some years ago and is able to generate the raw signal corresponding to extended scenes. However, it cannot account for the effects of sensor trajectory deviations with respect to the nominal straight-line path. This paper explores the possibility of extending the efficient Fourier domain simulation approach to the case of sensor trajectory deviations, which is more realistic for airborne SAR systems. We first of all obtain a general and compact Fourier domain formulation of the SAR raw signal in the presence of arbitrary trajectory deviations, and show that in this general case no efficient simulation scheme can be devised. However, we demonstrate that, if a narrow beam and slow trajectory deviation assumption is made, a full 2-D Fourier domain simulation can be used. This approach can be applied only to some SAR systems and/or trajectory deviations, but it has the advantage that processing time is practically not increased with respect to the nominal trajectory case. The validity limits of the approach are analytically evaluated. Some simulation results are finally presented in order to verify the effectiveness of the proposed simulation scheme. In another paper, which is the second part of this work, it will be shown that the narrow beam-slow deviation assumption can be relaxed, at the expense of computation efficiency, if a one-dimensional azimuth Fourier domain processing followed by a range time-domain integration is used View full abstract»

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  • Integration of Radar Interferometry and Laser Scanning for Remote Monitoring of an Urban Site Built on a Sliding Slope

    Page(s): 2335 - 2342
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    The Alpine village of Lamosano, Belluno, Italy, located near a wide and active landslide, has been seriously threatened by ground instabilities since 1960. In this paper, the results obtained by two different remote-monitoring techniques, synthetic aperature radar interferometry and three-dimensional laser-scanner imaging, planned for Lamosano hazard assessment, are presented. Both techniques compare images taken at different times to map and classify changes that occurred on the imaged scenario. The radar and laser data are gathered at the same dates with about ten-month temporal separation. The displacements measured separately by each of the two techniques highlight a similar sliding motion on the Lamosano village area, providing a good validation to each other and contributing to the definition of the village instability hazard View full abstract»

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  • Validating the SAR Wavenumber Shift Principle With the ERS–Envisat PS Coherent Combination

    Page(s): 2343 - 2351
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    Continuity of the European Remote Sensing Satellite Synthetic Aperture Radar (ERS SAR) archive by means of Envisat Advanced SAR (ASAR) data acquired from March 2002 has introduced the problem of the coherent combination of images coming from sensors with slightly different frequencies. The spectral shift principle states that in case of extended distributed targets, the frequency shift is equivalent to a change of looking angle. In this paper, the same principle is exploited to analyze the behavior of permanent scatterers (PSs) with an extension that is smaller than the ground resolution cell. The conditions under which the PSs identified by ERS can be continued by Envisat are then theoretically determined and experimentally validated. Moreover, this analysis shows that acquisitions characterized by different frequencies can be used to identify the slant-range position of scatterers with high subcell accuracy (tens of centimeters). From the processing side, a very precise images coregistration step is required to get the results described in this paper View full abstract»

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  • TOPSAR: Terrain Observation by Progressive Scans

    Page(s): 2352 - 2360
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (871 KB) |  | HTML iconHTML  

    In this paper, a novel (according to the authors' knowledge) type of scanning synthetic aperture radar (ScanSAR) that solves the problems of scalloping and azimuth-varying ambiguities is introduced. The technique employs a very simple counterrotation of the radar beam in the opposite direction to a SPOT: hence, the name terrain observation with progressive scan (TOPS). After a short summary of the characteristics of the ScanSAR technique and its problems, TOPSAR, which is the technique of design, the limits, and a focusing technique are introduced. A synthetic example based on a possible future system follows View full abstract»

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  • Two-Dimensional Variation Algorithm for Fractal Analysis of Sea SAR Images

    Page(s): 2361 - 2373
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (514 KB) |  | HTML iconHTML  

    This paper proposes a novel algorithm for estimating the fractal dimension of sea synthetic aperture radar (SAR) images. The algorithm is based on the variation method, and it is suitably designed for the analysis of sea SAR images. The SAR image fractal dimension is a feature that provides a measure of the image roughness. Such a feature can play an important role in the classification process for recognizing the presence of anomalies on the sea surface. The innovation aspects of this paper are listed as follows: (1) an extension of the variation method, which was proposed for the fractal analysis of one-dimensional signals, to the case of two-dimensional (2-D) functions; (2) a numerical formulation of the variation method, which is suitable for processing 2-D discrete signals; and (3) an optimization of the algorithm for sea SAR image analysis. The algorithm is tested and validated both on simulated and real ERS-1/2 Precision Image sea SAR images and compared with the classical estimation algorithm based on spectral analysis View full abstract»

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  • On the Extension of the Minimum Cost Flow Algorithm for Phase Unwrapping of Multitemporal Differential SAR Interferograms

    Page(s): 2374 - 2383
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    In this paper, an extension of the minimum cost flow (MCF) algorithm dealing with a sparse data grid, which allows the unwrapping of multitemporal differential synthetic aperture radar (SAR) interferograms for the generation of deformation time series, is presented. The proposed approach exploits both the spatial characteristics and the temporal relationships among multiple interferograms relevant to a properly chosen sequence. In particular, the presented solution involves two main steps: first of all, for each arc connecting neighboring pixels on the interferometric azimuth/range grid, the unwrapped phase gradients are estimated via the MCF technique applied in the temporal/perpendicular baseline plane. Following this step, these estimates are used as a starting point for the spatial-unwrapping operation implemented again via the MCF approach but carried out in the azimuth/range plane. The presented results, achieved on simulated and real European Remote Sensing satellite SAR data, confirm the effectiveness of the extended MCF unwrapping algorithm View full abstract»

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  • Late-Season Rural Land-Cover Estimation With Polarimetric-SAR Intensity Pixel Blocks and \sigma -Tree-Structured Near-Neighbor Classifiers

    Page(s): 2384 - 2392
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    Synthetic aperture radar (SAR) image classification for late-season rural land-cover estimation is investigated. A novel tree-structured nearest neighbor-like classifier is applied to polarimetric SAR intensity image pixel blocks. The novel tree structure, called a sigma-tree, is generated by an ordered summation of unweighted template refinements. Computation and memory costs of a sigma-tree classifier grow linearly. The reduced costs of sigma-tree classifiers are obtained with the tradeoff of a guarantee of nearest neighbor mappings. Causal-anticausal refinement-template design methods, combined with causal multiple-stage search engine structures, are shown to yield sequential search decisions that are acceptably near-neighbor mappings. The performance of a sigma-tree classifier is demonstrated for rural land-cover estimation with detected polarimetric C-band AirSAR pixel data. Experiments are conducted on various polarization/pixel block size combinations to evaluate the relative utility of spatial-only, polarimetric-only, and combined spatial/polarimetric classifier inputs View full abstract»

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  • Landmines Ground-Penetrating Radar Signal Enhancement by Digital Filtering

    Page(s): 2393 - 2406
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (911 KB) |  | HTML iconHTML  

    Until now, humanitarian demining has been unable to provide a solution to the landmine removal problem. Furthermore, new low-cost methods have to be developed quickly. While much progress has been made with the introduction of new sensor types, other problems have been raised by these sensors. Ground-penetrating radars (GPRs) are key sensors for landmine detection as they are capable of detecting landmines with low metal contents. GPRs deliver so-called Bscan data, which are, roughly, vertical slice images of the ground. However, due to the high dielectric permittivity contrast at the air-ground interface, a strong response is recorded at an early time by GPRs. This response is the main component of the so-called clutter noise, and it blurs the responses of landmines buried at shallow depths. The landmine detection task is therefore quite difficult, and a preprocessing step, which aims at reducing the clutter, is often needed. In this paper, a difficult case for clutter reduction, that is, when landmines and clutter responses overlap in time, is presented. A new and simple clutter removal method based on the design of a two-dimensional digital filter, which is adapted to Bscan data, is proposed. The designed filter must reduce the clutter on Bscan data significantly while protecting the landmine responses. In order to do so, a frequency analysis of a clutter geometrical model is first led. Then, the same process is applied to a geometrical model of a signal coming from a landmine. This results in building a high-pass digital filter and determining its cutoff frequencies. Finally, simulations are presented on simulated and real data, and a comparison with the classical clutter removal algorithm is made View full abstract»

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  • Electrical Impedance Tomographic Imaging of Buried Landmines

    Page(s): 2407 - 2420
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    A prototype confirmation landmine detector, based on electrical impedancetomography (EIT), which can operate under realistic environmental conditions, has been developed. Laboratory and field experiments demonstrated that it is possible to reliably reconstruct, on the scale of the electrode spacing (ES) (in width and depth), conductivity perturbations due to a shallow buried antitank mine or a similar object in a variety of soils (black earth, clay, sand) down to depths equal to the dimensions of the object (1-1.5 ES, equivalent to 14-21 cm for a 64-electrode 1 m times 1 m array). These represent the first EIT images of real landmines computed from measured data. Occasional problems were encountered with the electrical contact in very dry soils, with excessive insertion pressure being required for reliable electrode contact. However, poor contacts could be detected, and the offending probe was either reinserted or compensation was applied. A matched filter detection algorithm based on a replica of the object of interest was developed and shown to effectively reduce the false alarm rate of the detector. EIT is especially suited for wet lands and underwater, where other mine detectors perform poorly. Experiments in a water-and sediment-filled tank have demonstrated that detection of minelike objects in such an environment with a submerged array is feasible. These experiments represent the first EIT measurements of targets using an electrode array submerged underwater. EIT may also have an application in locating intact mines in the berms formed by mine-clearing equipment. The EIT sensor head could be made cheaply enough to be disposable and remotely inserted to improve safety View full abstract»

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  • Modeling and Migration of 2-D Georadar Data: A Stationary Phase Approach

    Page(s): 2421 - 2429
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (209 KB) |  | HTML iconHTML  

    This paper presents the basic kinematic and dynamic imaging and migration equations for zero-offset two-dimensional georadar profiling. The kinematic equations are derived from simple considerations of spatial impulse responses and a generating function. The dynamic equations follow from a multidimensional stationary phase approximation to the infinite spectral integrals. They show how the radar signal (amplitude and phase) depends on the shape and curvature of the reflector. The imaging equations are evaluated for the special cases of a point scatterer, a continuous reflector, and a terminating reflector. A general formula is developed by which to migrate an arbitrary shaped event of variable amplitude on the georadar section View full abstract»

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  • Doppler Spectra From a Two-Dimensional Ocean Surface at L-Band

    Page(s): 2430 - 2437
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    An approximate time-harmonic three-dimensional electromagnetic boundary-integral method, the small-slope integral equation, is combined with a series expansion of the Creamer surface representation at second order with respect to the height, denoted by Creamer (2). The resulting model provides at low numerical cost simulations of the nonlinear ocean surface Doppler spectrum at L-band. As a result of approximations, the model is designed for a low-wind speed, typically up to 5 m/s. It is shown that applying directly a second-order model such as Creamer (2) to a semiempirical sea surface spectrum induces an unrealistic magnification of small-scale roughness that is involved in the scattering process at microwave frequencies. This paper thus proposes an undressed version of the Pierson-Moskowitz spectrum that corrects this artifact. Full-polarized Doppler simulations at L-band and 70deg incidence are presented. Effects of the surface nonlinearities are outlined, and the simulated Doppler spectra show correct variations with respect to wind speed and direction View full abstract»

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  • Analysis of Surface Roughness Heterogeneity and Scattering Behavior for Radar Measurements

    Page(s): 2438 - 2444
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    The use of a theoretical backscatter model to analyze medium to low spatial resolution microwave data is still very complicated, particularly because of the difficulty in defining a unique roughness parameter, capable of adequately representing heterogeneous terrain. In this paper, an approach is proposed for roughness analysis and the modeling of backscattering, under conditions of surface heterogeneity. This paper is based on the use of a semiempirical backscattering model, defined with a single roughness parameter Zs=s2/l (s being the root mean square surface height and l the correlation length). The proposed backscattering model has been validated with integral equation model simulations, for high radar incidence angles, and within its domain of roughness validity. A range of experimental measurements was used to validate the model expressions. The effective low spatial resolution roughness, inferred from signals backscattered from a surface of heterogeneous roughness, is defined for different roughness classes View full abstract»

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  • Efficient Numerical Simulation of Axisymmetric Electromagnetic Induction Measurements Using a High-Order Generalized Extended Born Approximation

    Page(s): 2445 - 2453
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    This paper develops a high-order generalized extended Born approximation (Ho-GEBA) for the numerical simulation of electromagnetic scattering due to rock formations that exhibit axial symmetry around a wellbore. The resulting equations of Ho-GEBA are solved with a numerical procedure that is as efficient as the extended Born approximation (EBA). With the acceleration of a fast Fourier transform, the operation count is proportional to O(CN), where N is the total number of spatial discretization cells and CLtN is a constant that depends on the number of discretization cells in the radial direction. Ho-GEBA remains accurate in the near-source scattering region and accounts for multiple scattering in the presence of large conductivity contrasts and relatively large frequencies. Numerical exercises conclusively indicate that the accuracy of Ho-GEBA is superior to that of EBA and the first-order Born approximation while maintaining the same level of algorithmic efficiency. These exercises are carried out on a variety of source-receiver configurations and frequencies typical of single-well borehole induction measurements View full abstract»

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  • Modeling Broadband Electromagnetic Induction Responses of 2-D Multilayered Structures

    Page(s): 2454 - 2460
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    Dual-coil frequency-domain electromagnetic induction (EMI) systems are commonly used as detectors of buried metallic objects, but they are also increasingly used for environmental purposes such as detection of contaminant plumes and archaeological prospection. Usually, data are analyzed directly by visualizing the in-phase and quadrature components, and also by applying one-dimensional inversion methods. Besides, there exist three-dimensional (3-D) forward and inverse modeling codes based on finite-difference techniques, but these methods are not routinely applied because their computation cost for real geophysical situations is still too high. The computation cost is significantly lower for two-dimensional (2-D) structures since this problem is not 3-D but 2.5-D. Few 2.5-D methods have been published in the last years, based on finite-element techniques, but for the case of electric dipole sources. In this paper, the authors present a 2.5-D forward-modeling algorithm, based on Rayleigh-Fourier expansions, for calculating the response of 2-D multilayered earth with irregular boundaries to the magnetic-dipole sources. Using this code, the authors numerically simulated the dual-coil frequency-domain EMI response of a soil model that could be found in environmental research. They considered a buried nonmetallic object, conductive with respect to the host media, and calculated its response for different orientations of the transmitter and receiver coils. The best resolution for detecting and characterizing this object corresponded to the configuration in which the axes of the transmitter and receiver dipoles were parallel to the ground surface and perpendicular to the symmetry axis of the buried objects, and the axis of the instrument was parallel to that symmetry axis. Finally, the authors interpreted the field data from a profile exhibiting resistive anomalies, corresponding to underground contamination, by using their forward code and a trial-and-error procedure. Thi- - s profile had been previously characterized through the inversion of dipole-dipole electrical data. They considered that result to select their starting multilayered model. They obtained a good correlation between the EMI data and the synthetic response of the final multilayered model. Besides, this model is consistent with the image of the electrical inversion. During the modeling process, the method showed to be practical and versatile and to have a good convergence View full abstract»

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  • Melt Detection in Antarctic Ice Shelves Using Scatterometers and Microwave Radiometers

    Page(s): 2461 - 2469
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    Ku-band dual-polarization radar backscatter measurements from the SeaWinds-on-QuikSCAT scatterometer are used to determine periods of surface freeze and melt in the Antarctic ice shelves. The normalized horizontal-polarization radar backscatter (sigmao) and backscatter polarization ratio are used in maximum-likelihood estimation of the ice state. This method is used to infer the daily ice-surface conditions for 25 study locations located on the Ronne, Ross, Larsen, Amery, Shackleton, and other ice shelves. The temporal and spatial variations of the radar response are observed for various neighborhood sizes surrounding each given location during the study period. Criteria for determining the dates of melt onset and freeze-up for each Austral summer are presented. Validation of the ice-state and melt-onset date estimates is performed by analyzing the corresponding brightness temperature (Tb) measurements from Special Sensor Microwave/Imager (SSM/I) radiometers. QuikSCAT sigmao measurements from 1999 to 2003 are analyzed and found to be effective in determining periods of melt in Antarctic ice sheets at high temporal and spatial resolutions. These estimates can be used in studies of the climatic effects of the seasonal and interannual melting of the Antarctic ice sheets View full abstract»

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  • Correction for Rain Path Specific and Differential Attenuation of X-Band Dual-Polarization Observations

    Page(s): 2470 - 2480
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    The accuracy of attenuation correction for X-band reflectivity (Z H) and differential reflectivity (ZDR) measurements in rainfall is analyzed using coincident X-band and S-band polarimetric radar observations collected during the International H2O Project in the period of May-June 2002 at northwestern Oklahoma. Two distinct attenuation correction techniques that use the differential propagation phase shift (PhiDP) information, which is not a power-dependent measurement, as a means to provide independent estimates of path-integrated attenuation are assessed. The study is facilitated by nonattenuated X-band ZH and ZDR profiles simulated based on raindrop size distribution parameters retrieved from matched multiparameter (ZH, ZDR, and KDP) S-band observations. The major outcome of this assessment is that PhiDP-based attenuation correction for both techniques can reach almost unbiased measurements (within 5% mean relative error) and low random error (15-20% relative standard deviation). The study shows moderate differences in the error statistics of the evaluated techniques. The sensitivity of attenuation correction uncertainty with respect to the assumed variability in raindrops' oblateness-size relation and the noise in PhiDP measurement is also shown View full abstract»

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  • Stereo Cloud Heights From Multispectral IR Imagery via Region-of-Interest Segmentation

    Page(s): 2481 - 2491
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    Multispectral thermal imagery acquired from low Earth orbit was used to develop a method of cloud-height determination that applies image brightness temperature histograms and region-of-interest (ROI) image segmentation as a processing step prior to stereo-height retrieval. The National Aeronautics and Space Administration's Infrared Spectral Imaging Radiometer (ISIR) acquired all imagery during the August 1997 STS-85 mission of the Space Shuttle Discovery. ISIR, the first Earth-observing spectroradiometer to employ an uncooled large-format microbolometer-array focal plane, provided continuous coverage in four spectral bands along track in an 80-km-wide swath. ROI segmentation created binary cloud masks ranging over brightness temperatures in the imagery for which the parallax was determined by a two-dimensional correlation method, allowing stereo heights to be determined using the standard parallax equations. A subpixel parallax algorithm allowed stereo heights to be determined with a precision of roughly plusmn0.39 km for clouds in the observed altitude range of 0.5-10 km View full abstract»

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  • Global Simulation of Brightness Temperatures at 6.6 and 10.7 GHz Over Land Based on SMMR Data Set Analysis

    Page(s): 2492 - 2505
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    In the framework of the Soil Moisture and Ocean Salinity mission, a two-year (1987-1988) global simulation of brightness temperatures (TB) at L-band was performed using a simple model [L-band microwave emission of the biosphere, (L-MEB)] based on radiative transfer equations. However, the lack of alternative L-band spaceborne measurements corresponding to real-world data prevented from assessing the realism of the simulated global-scale TB fields. In this study, using a similar modeling approach, TB simulations were performed at C-band and X-band. These simulations required the development of C-MEB and X-MEB models, corresponding to the equivalent of L-MEB at C-band and X-band, respectively. These simulations were compared with Scanning Multichannel Microwave Radiometer (SMMR) measurements during the period January to August 1987 (corresponding to the end of life of the SMMR mission). A sensitivity study was also carried out to assess, at a global scale, the relative contributions of the main MEB parameters (particularly the roughness and vegetation model parameters). Regional differences between simulated and measured TBs were analyzed, discriminating possible issues either linked to the radiative transfer model (C-MEB and X-MEB) or due to land surface simulations. A global agreement between observations and simulations was discussed and allowed to evaluate regions where soil moisture retrievals would give best results. This comparison step made at C-band and X-band allowed to better assess how realistic and/or accurate the L-band simulations could be View full abstract»

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  • An Analysis of Angle-Based With Ratio-Based Vegetation Indices

    Page(s): 2506 - 2513
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (226 KB) |  | HTML iconHTML  

    Remotely sensed, angle-based vegetation indices that measure vegetation amounts by the angle between an approximated soil line and a simulated vegetation isoline in the red-near-infrared reflectance space were developed and evaluated in this paper. Unsalan and Boyer previously proposed an angle-based vegetation index, thetas (denoted as thetas NDVI in this paper), based on the normalized difference vegetation index (NDVI) with the objective of overcoming the saturation problem in the NDVI. However, thetasNDVI did not consider strong soil background influences present in the NDVI. To reduce soil background noise, an angle-based vegetation index, thetasSAVI , based on the soil-adjusted vegetation index (SAVI), was derived using trigonometric analysis. The performance of thetasNDVI and thetasSAVI was evaluated and compared with their corresponding vegetation indices, NDVI and SAVI. The soil background influence on thetasNDVI was found to be as significant as that on the NDVI. thetasNDVI was found to be more sensitive to vegetation amount than the NDVI at low vegetation density levels, but less sensitive to vegetation fraction at high vegetation density levels. Thus, the saturation effect at high vegetation density levels encountered in the NDVI was not mitigated by thetasNDVI. By contrast, thetasSAVI exhibited insignificant soil background effects and weaker saturation, as in SAVI, but also improved upon the dynamic range of SAVI. Analyses and evaluation suggest that thetasSAVI is an optimal vegetation index to assess and monitor vegetation cover across the entire range of vegetation fraction density levels and over a wide variety of soil backgrounds View full abstract»

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  • Bounds on the Variance in the Pattern Matching Criteria

    Page(s): 2514 - 2522
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    The Backus-Gilbert (BG) method is used throughout the satellite community as a noise/pattern adjustment technique. To proceed with the study of the discrete BG (DBG) method, the fundamental properties of the noise/pattern tradeoff need to be studied. This paper investigates the pattern matching criteria the DBG method is based on and how noise minimization is incorporated into the solution. In particular, the bounded nature of the variance and the behavior of the tradeoff curve are shown explicitly. The penalty function is studied, and restrictions on its definition are given; problems with the common choice of J=1 are also presented. The case of a positive semidefinite error covariance matrix is analyzed and the uniqueness of the solution evaluated. This paper serves to provide a thorough theoretical discussion of the noise/pattern tradeoff properties and the practical issues associated with its implementation View full abstract»

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  • Automatic Construction of Building Footprints From Airborne LIDAR Data

    Page(s): 2523 - 2533
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (782 KB) |  | HTML iconHTML  

    This paper presents a framework that applies a series of algorithms to automatically extract building footprints from airborne light detection and ranging (LIDAR) measurements. In the proposed framework, the ground and nonground LIDAR measurements are first separated using a progressive morphological filter. Then, building measurements are identified from nonground measurements using a region-growing algorithm based on the plane-fitting technique. Finally, raw footprints for segmented building measurements are derived by connecting boundary points, and the raw footprints are further simplified and adjusted to remove noise caused by irregularly spaced LIDAR measurements. Data sets from urbanized areas including large institutional, commercial, and small residential buildings were employed to test the proposed framework. A quantitative analysis showed that the total of omission and commission errors for extracted footprints for both institutional and residential areas was about 12%. The results demonstrated that the proposed framework identified building footprints well View full abstract»

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  • Methodological Proposal for Multispectral Stereo Matching

    Page(s): 2534 - 2538
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB) |  | HTML iconHTML  

    Remote sensors have begun to capture digital stereoscopic data. Although still monospectral (usually panchromatic), the capture of multispectral or hyperspectral stereoscopic data is just a matter of time. Digital photogrammetric workstations use area-based stereo-matching techniques based on the Pearson (product-moment) correlation coefficient. This is a technique that is not intended to take advantage of the multispectral data. The authors propose a new method that 1) can handle this multispectral information and 2) can take advantage of the spatial relations between pixel locations. The method is based on multidimensional scaling and Procrustes analysis. Our results indicate that the proposed new technique renders more robust results than classical methodology when noise in the original data is introduced 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