Descripteur
Termes IGN > sciences humaines et sociales > économie > macroéconomie > secteur secondaire > technologies spatiales > vitesse radiale
vitesse radiale |
Documents disponibles dans cette catégorie (7)
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
![Tris disponibles](./images/orderby_az.gif)
Etendre la recherche sur niveau(x) vers le bas
Image-based target detection and radial velocity estimation methods for multichannel SAR-GMTI / Kei Suwa in IEEE Transactions on geoscience and remote sensing, vol 55 n° 3 (March 2017)
![]()
[article]
Titre : Image-based target detection and radial velocity estimation methods for multichannel SAR-GMTI Type de document : Article/Communication Auteurs : Kei Suwa, Auteur ; Kazuhiko Yamamoto, Auteur ; Masayoshi Tsuchida, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 1325 - 1338 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande Ku
[Termes IGN] détection de cible
[Termes IGN] estimation statistique
[Termes IGN] image radar moirée
[Termes IGN] objet mobile
[Termes IGN] vitesse radialeRésumé : (Auteur) In order to enhance the performance of spaceborne synthetic aperture radar-ground moving target indication (SAR-GMTI) systems, multichannel systems with large and preferably nonuniform baselines are required. In this paper, SAR-GMTI algorithms for multichannel SAR systems, which we call multichannel displaced phase center antenna (DPCA), multichannel along track interferometry (ATI), and multichannel DPCA-ATI, are presented. Multichannel DPCA is a deterministic algorithm for clutter and azimuth ambiguity suppression. It successfully suppresses not only uniform azimuth ambiguities but also nonuniform isolated ones, since it does not require uniform clutter covariance assumption as adaptive algorithms do. Multichannel ATI and multichannel DPCA-ATI are the algorithms for target radial velocity estimation. Both of them reduce the target radial velocity ambiguities, which arise with the long baseline systems, by exploiting the multiple receive channel signals. And multichannel DPCA-ATI further achieves robust performance to clutter influence by suppressing the clutter and the azimuth ambiguity in advance. The performances of the proposed algorithms are shown through airborne Ku-band three-channel SAR experiments. It is shown that the multichannel DPCA suppresses strong azimuth ambiguity up to more than 20 dB, and the accuracy of the radial velocity estimation of the multichannel DPCA-ATI is on the order of 0.1 m/s. Furthermore, statistical performance analysis is presented to discuss the potential performance on the spaceborne system. Numéro de notice : A2017-152 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2622712 En ligne : https://doi.org/10.1109/TGRS.2016.2622712 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84684
in IEEE Transactions on geoscience and remote sensing > vol 55 n° 3 (March 2017) . - pp 1325 - 1338[article]
Titre : Robotics, vision and control Type de document : Monographie Auteurs : Peter Corke, Auteur Editeur : Springer International Publishing Année de publication : 2017 Importance : 570 p. Format : 21 x 27 cm ISBN/ISSN/EAN : 978-3-319-54413-7 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Intelligence artificielle
[Termes IGN] Matlab
[Termes IGN] navigation inertielle
[Termes IGN] robot mobile
[Termes IGN] robotique
[Termes IGN] traitement d'image
[Termes IGN] vision par ordinateur
[Termes IGN] vitesse radialeRésumé : (éditeur) Robotic vision, the combination of robotics and computer vision, involves the application of computer algorithms to data acquired from sensors. The research community has developed a large body of such algorithms but for a newcomer to the field this can be quite daunting. For over 20 years the author has maintained two open-source MATLAB® Toolboxes, one for robotics and one for vision. They provide implementations of many important algorithms and allow users to work with real problems, not just trivial examples. This book makes the fundamental algorithms of robotics, vision and control accessible to all. It weaves together theory, algorithms and examples in a narrative that covers robotics and computer vision separately and together. Using the latest versions of the Toolboxes the author shows how complex problems can be decomposed and solved using just a few simple lines of code. The topics covered are guided by real problems observed by the author over many years as a practitioner of both robotics and computer vision. It is written in an accessible but informative style, easy to read and absorb, and includes over 1000 MATLAB and Simulink® examples and over 400 figures. The book is a real walk through the fundamentals of mobile robots, arm robots. then camera models, image processing, feature extraction and multi-view geometry and finally bringing it all together with an extensive discussion of visual servo systems. This second edition is completely revised, updated and extended with coverage of Lie groups, matrix exponentials and twists; inertial navigation; differential drive robots; lattice planners; pose-graph SLAM and map making; restructured material on arm-robot kinematics and dynamics; series-elastic actuators and operational-space control; Lab color spaces; light field cameras; structured light, bundle adjustment and visual odometry; and photometric visual servoing. Note de contenu : 1- Introduction
2- Representing Position and Orientation
3- Time and Motion
4- Mobile Robot Vehicles
5- Navigation
6- Localization
7- Robot Arm Kinematics
8- Manipulator Velocity
9- Dynamics and Control
10- Light and Color
11- Image Formation
12- Images and Image Processing
13- Image Feature Extraction
14- Using Multiple Images
15- Vision-Based Control
16- Advanced Visual ServoingNuméro de notice : 25794 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE Nature : Monographie En ligne : https://doi.org/10.1007/978-3-319-54413-7 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95024 Geometry-information-aided efficient radial velocity estimation for moving target imaging and location based on Radon transform / Xuepan Zhang in IEEE Transactions on geoscience and remote sensing, vol 53 n° 2 (February 2015)
![]()
[article]
Titre : Geometry-information-aided efficient radial velocity estimation for moving target imaging and location based on Radon transform Type de document : Article/Communication Auteurs : Xuepan Zhang, Auteur ; Guisheng Liao, Auteur ; Shengqi Zhu, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 1105 - 1117 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] géométrie
[Termes IGN] image radar moirée
[Termes IGN] objet mobile
[Termes IGN] transformation de Radon
[Termes IGN] vitesse radialeRésumé : (Auteur) Real-time radial velocity estimation is a key challenge for moving target imaging and location in current single-antenna synthetic aperture radar (SAR)-ground moving target indication systems. Since the conventional methods suffer from ambiguity, complexity realization, or heavy computation load for fast moving target motion estimation, this paper emphasizes the estimation efficiency by simple realization. An efficient Radon transform (RT) estimation is proposed to estimate the radial velocity of fast moving target by utilizing the geometry information, and much more geometry information is exploited to realize clutter cancellation, noise cancellation, and estimation error minimizing in the RT domain, which is not proposed by the others. With only two to four angles used to calculate rather than search for the radial velocity of moving targets, the proposed methods simplify the conventional range and angle (2-D) searching procedure into several time range (1-D) searching procedure efficiently. The theoretical and experimental analysis provides qualitative and quantitative evaluations into the effectiveness of the proposed methods. In the single-antenna SAR system, the proposed methods can estimate the radial velocity of fast moving target efficiently and accurately in high signal to clutter plus noise ratio scenarios. Numéro de notice : A2015-110 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2334322 En ligne : https://doi.org/10.1109/TGRS.2014.2334322 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75628
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 2 (February 2015) . - pp 1105 - 1117[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 065-2015021 RAB Revue Centre de documentation En réserve L003 Disponible
Titre : The role of orbit errors in processing of satellite altimeter data Type de document : Rapport Auteurs : E.J.O. Schrama, Auteur Editeur : Delft : Netherlands Geodetic Commission NGC Année de publication : 1989 Collection : Netherlands Geodetic Commission Publications on Geodesy Sous-collection : New series num. 33 Importance : 170 p. Format : 20 x 28 cm ISBN/ISSN/EAN : 978-90-6132-239-9 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Technologies spatiales
[Termes IGN] altimétrie satellitaire par radar
[Termes IGN] données altimétriques
[Termes IGN] invariance
[Termes IGN] mécanique orbitale
[Termes IGN] orbitographie
[Termes IGN] pesanteur terrestre
[Termes IGN] Seasat
[Termes IGN] vitesse radialeRésumé : (auteur) The problem of radial orbit errors in processing of satellite altimeter data is largely due to the inaccuracy of the gravity model which is required for the computation of the trajectory of the spacecraft. A commonly used technique for removing these errors consists of minimizing the crossover differences of profiles measured by the altimeter radar.
Several versions of the technique of least squares crossover minimization have been investigated using either SEASAT observations or simulated data. In these adjustments coefficients of error functions are estimated which are either locally defined over short arc segments, globally over long arc segments, or continuously over an entire arc having a length of several days. The solution of the corresponding normal equations consists of a homogeneous and a particular part.
For each crossover minimization problem (CMP) the homogeneous solution is always given as an analytical expression describing the invariances of the altimetric sea surface with respect to the crossover differences. These invariances are described by a surface deformation function which is characteristic for the problem in question. The number of coefficients in this function equals to the rank defect of the normal matrix in the CMP.
For the particular solution of a local CMP (using "tilt and bias" functions) it was found that 2 non-intersecting and non-overlapping master arc segments have to be fixed. However for global chronological segmented CMP's (using 3 parameter sine-cosine functions) only 1 master arc segment needs to be fixed for a particular solution. For continuous CMP's a particular solution is found by including 9 constraint equations in the form of pseudo observation equations. In this case the error function consists of a Fourier series truncated at a cutoff frequency of 2.3 cycles per revolution including a 2 parameter function modeling a long periodic effect in the orbit.
The underlying problem of gravitational radial orbit errors is described by means of the linear perturbations theory, which is based on the Lagrange planetary equations. Additionally the problem is formulated by means of the Hill equations describing perturbed satellite motions in an idealized circular orbit. It is shown that the non-resonant particular radial solution of the Hill equations coincides with the first-order radial solution derived from the linear perturbations theory assuming a
near circular orbit.
The first-order radial solution has been compared with a simulated signal derived by numerical integration of the equations of motion. The simulated signal consists of the radial differences between two trajectories (resembling the SEASAT 3 day repeat configuration) integrated with different gravity models. It was found that the analytical orbit error model resembles closely the simulated signal after removal of a long periodic effect.
The validity of the general solutions of two global CMP's has been investigated by means of a simulation experiment. In this experiment crossover differences are simulated by means of the radial orbit error signal described above. In a second step it is attempted to reconstruct this signal by minimizing the simulated differences.
This experiment revealed that the general solution of the segmented CMP appears to be hampered by unrealistic velocity discontinuity effects of successive arc segment error functions. In addition, it fails to describe the C11 and S11 and higher degree and order components of a geographically correlated radial orbit error. This is not surprising since one can prove that the homogeneous solution of the segmented CMP (without velocity discontinuities) corresponds to the C00 and C10 component of the geographically correlated radial orbit error. For this reason the global segmented CMP is reformulated in a continuous approach where it is shown that the homogeneous solution coincides with the geographically correlated radial orbit error. Computations showed that the simulated signal deviates to approximately 15 cm r.m.s. with respect to the general solution of the continuous CMP.
Employing the latter technique 5 independent particular solutions of a radial orbit error signal have been computed from SEASAT crossover data. These solutions appear to be highly correlated and suggest the presence of a disturbing effect likely to be caused by gravity modeling errors. Additionally it was found that the individual solutions resemble a concentration of signal near the once per revolution frequency in the radial orbit error spectrum. This solution could in principle be used to improve a part of the gravity model that is used in the trajectory computation of the satellite.
In the last part an integrated approach is described where the problem of modeling errors in the orbit, the geoid and the permanent part of the sea surface topography (PST) caused by ocean circulation are considered simultaneously. It is argued that an application of the integrated approach is justified if simultaneously gravity model improvement is performed employing tracking data of other satellites at different inclinations and eccentricities. Other aspects of the integrated approach concern the modeling problems of the PST field, an omission effect of the gravity field and the relation with the global continuous CMP.Numéro de notice : 57963 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Rapport de recherche DOI : sans En ligne : https://www.ncgeo.nl/downloads/33Schrama.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=60322 Exemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 57963-01 21.10 Livre Centre de documentation Technologies spatiales Disponible 57963-02 21.10 Livre Centre de documentation Technologies spatiales Disponible
Titre : Altimetry, orbits and tides Type de document : Monographie Auteurs : Oscar L. Colombo, Auteur Editeur : Washington : National Aeronautics and Space Administration NASA Année de publication : 1984 Collection : NASA Technical Memorandum Importance : 173 p. Format : 21 x 30 cm Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] marée océanique
[Termes IGN] orbite képlerienne
[Termes IGN] orbitographie
[Termes IGN] poursuite de satellite
[Termes IGN] surface de la mer
[Termes IGN] vitesse radialeRésumé : (Auteur) This report explains the nature of the orbit error and its effect on the sea surface heights calculated with satellite altimetry. It includes an introduction of the elementary concepts of celestial mechanics required to follow a general discussion of the problem. This leads to a detailcd consideration ot errors in the orbits of satellites with precisely repeating groLind tracks (SEASAT, TOPEX, ERS1, POSEIDON, amongst past and future altimeter satellites). The theoretical conclusions are illustrated with the numerical results of computer simulations. The nature of the errors in this type of orbits is such that this error can be filtered out by using height differences along repeating (overlapping) passes. This makes them particularly valuable for the study and monitoring of changes in the sea surface, such as tides. The report ends with a presentation of some elements of tidal theory, showing how these principles can be combined with those pertinent to the orbit error to make direct maps of the tides using altimetry. Numéro de notice : 18679 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55445 Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 18679-01 21.10 Livre Centre de documentation Technologies spatiales Disponible PermalinkPermalink