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The objective of this work is to use the compressive sensing in the field of the space exploration. The compressive sensing theory affirms that an image can be retrieved taking only fewer mea- surement with respect to the minimum number dictated by the Nyquist theory. Contrarily to the classical method of acquisition of an image, the CS technique allows to create lensless cam- eras like the Flatcam, the NoRDS-CAIC and the DiffuserCam. The drawback of this technique is the need of a decoding algorithm for the reconstruction of the original image. The reconstruction method of the images is not unique, there are classical methods, that use the total variation minimization, and the deep learning methods. This work analyzes and com- pares two classical and two deep learning methods in order to find the best method for the space application. The simulations have found that the method using the deep learning approach give optimum results. The images can be well-reconstructed already with a number of measurement that is the 30% of the size of the images in less than one second. In order to practically understand the principle of the compressive sensing, an example of the DiffuserCam has been constructed in the laboratory. The camera is composed only by a diffuser and a sensor. The experience gave great results, the images have been reconstructed with great quality in short time. Finally, the compressive sensing seems to be fascinating for the space application. This tech- nique allows to suppress the compressing board because the data are taken already compressed. The suppression of the compression board reduces the mass and especially the power budgets. Moreover, the post-processing on board allows the reduction of the downlink transmission. The compressive sensing in space exploration finds its application especially in the infrared spectral band. In fact, the infrared detectors are too expensive and the compressive sensing instruments uses the single pixel detectors that are cheaper
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Compressed sensing (Telecommunication) --- Biosensing Techniques --- Medical innovations. --- Innovations, Medical --- Medicine --- Medical technology --- Technological innovations --- Compressive sensing (Telecommunication) --- Sensing, Compressed (Telecommunication) --- Sparse sampling (Telecommunication) --- Signal processing --- Innovations
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This first book on greedy approximation gives a systematic presentation of the fundamental results. It also contains an introduction to two hot topics in numerical mathematics: learning theory and compressed sensing. Nonlinear approximation is becoming increasingly important, especially since two types are frequently employed in applications: adaptive methods are used in PDE solvers, while m-term approximation is used in image/signal/data processing, as well as in the design of neural networks. The fundamental question of nonlinear approximation is how to devise good constructive methods (algorithms) and recent results have established that greedy type algorithms may be the solution. The author has drawn on his own teaching experience to write a book ideally suited to graduate courses. The reader does not require a broad background to understand the material. Important open problems are included to give students and professionals alike ideas for further research.
Approximation theory. --- Theory of approximation --- Functional analysis --- Functions --- Polynomials --- Chebyshev systems --- Compressed sensing (Telecommunication) --- Compressive sensing (Telecommunication) --- Sensing, Compressed (Telecommunication) --- Sparse sampling (Telecommunication) --- Signal processing
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Compressed sensing is an emerging field that allows for the recovery of a sparse signal from fewer measurements than permitted by the Nyquist theorem. This new paradigm can be used to create new imager architectures that are simpler, more compact, and cheaper than traditional imagers, acquiring images in a compressed manner and thereby reducing the amount of data to handle. These characteristics are appealing for potential implementation in Earth observation satellites, where size and weight are critical factors, and where the amount of collected data is substantial, with limited storage capacity and transfer rates to the ground. This master’s thesis focuses on the implementation of the optical part of a compressive sensing imager in the laboratory, with the objective of performing a particular compressive sensing reconstruction method, known as inpainting. A comprehensive review of the state of the art in compressive sensing and various imager architectures is first provided. Afterwards, the design of the instrument and the selection of all its components are extensively detailed. A digital micromirror device is used for producing incomplete, damaged images of a scene, and a camera detector records the resulting image. Subsequently, a calibration procedure for the damaged images was established to prepare them for reconstruction through inpainting. This calibration includes dark and fl at frame corrections, as well as post-reconstruction image perspective correction. The instrument’s point spread function is also measured, and a dithering method is implemented to improve its resolution. Furthermore, the pattern mask used for the reconstruction is studied and calibrated using morphological erosion.
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Compressed sensing is an exciting, rapidly growing field, attracting considerable attention in electrical engineering, applied mathematics, statistics and computer science. This book provides the first detailed introduction to the subject, highlighting recent theoretical advances and a range of applications, as well as outlining numerous remaining research challenges. After a thorough review of the basic theory, many cutting-edge techniques are presented, including advanced signal modeling, sub-Nyquist sampling of analog signals, non-asymptotic analysis of random matrices, adaptive sensing, greedy algorithms and use of graphical models. All chapters are written by leading researchers in the field, and consistent style and notation are utilized throughout. Key background information and clear definitions make this an ideal resource for researchers, graduate students and practitioners wanting to join this exciting research area. It can also serve as a supplementary textbook for courses on computer vision, coding theory, signal processing, image processing and algorithms for efficient data processing.
Signal processing. --- Wavelets (Mathematics). --- Signal processing --- Wavelets (Mathematics) --- Compressed sensing (Telecommunication) --- Compressive sensing (Telecommunication) --- Sensing, Compressed (Telecommunication) --- Sparse sampling (Telecommunication) --- Wavelet analysis --- Harmonic analysis --- Processing, Signal --- Information measurement --- Signal theory (Telecommunication) --- telecommunicatie
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Optical fiber communication --- Compressed sensing (Telecommunication) --- Quality control. --- Compressive sensing (Telecommunication) --- Sensing, Compressed (Telecommunication) --- Sparse sampling (Telecommunication) --- Signal processing --- Fiber-optic communication --- Fiber optic telecommunication --- Optical communications --- Fiber optics
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This book presents the state of the art in sparse and multiscale image and signal processing, covering linear multiscale transforms, such as wavelet, ridgelet, or curvelet transforms, and non-linear multiscale transforms based on the median and mathematical morphology operators. Recent concepts of sparsity and morphological diversity are described and exploited for various problems such as denoising, inverse problem regularization, sparse signal decomposition, blind source separation, and compressed sensing. This book weds theory and practice in examining applications in areas such as astronomy, biology, physics, digital media, and forensics. A final chapter explores a paradigm shift in signal processing, showing that previous limits to information sampling and extraction can be overcome in very significant ways. Matlab and IDL code accompany these methods and applications to reproduce the experiments and illustrate the reasoning and methodology of the research are available for download at the associated web site.
Transformations (Mathematics) --- Signal processing. --- Image processing. --- Sparse matrices. --- Wavelets (Mathematics) --- Wavelet analysis --- Harmonic analysis --- Spare matrix techniques --- Matrices --- Pictorial data processing --- Picture processing --- Processing, Image --- Imaging systems --- Optical data processing --- Processing, Signal --- Information measurement --- Signal theory (Telecommunication) --- Algorithms --- Differential invariants --- Geometry, Differential --- Compressed sensing (Telecommunication) --- Compressive sensing (Telecommunication) --- Sensing, Compressed (Telecommunication) --- Sparse sampling (Telecommunication) --- Signal processing
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Quantum optics has received a lot of attention in recent decades due to the handiness and versatility of optical systems, which have been exploited both to study the foundations of quantum mechanics and for various applications. In this Special Issue, we collect some articles and a review focusing on some research activities that show the potential of quantum optics in the advancement of quantum technologies.
Research & information: general --- Physics --- integrated photonics --- quantum optics --- quantum simulation --- mesoscopic quantum states of light --- nonclassical photon-number correlations --- lossy transmission channels --- quantum state engineering --- nonlinear interferometer --- spontaneous four-wave mixing --- quantum message authentication --- quantum three-pass protocol --- Gao's forgery --- swap test --- conditional states --- silicon photomultipliers --- optical cross-talk --- nonclassicality --- quantum imaging --- plenoptic imaging --- quantum correlations --- SPAD arrays --- quantum fisher information --- compressive sensing --- quantum finite automata --- periodic languages --- confidence amplification --- photodetection --- integrated photonics --- quantum optics --- quantum simulation --- mesoscopic quantum states of light --- nonclassical photon-number correlations --- lossy transmission channels --- quantum state engineering --- nonlinear interferometer --- spontaneous four-wave mixing --- quantum message authentication --- quantum three-pass protocol --- Gao's forgery --- swap test --- conditional states --- silicon photomultipliers --- optical cross-talk --- nonclassicality --- quantum imaging --- plenoptic imaging --- quantum correlations --- SPAD arrays --- quantum fisher information --- compressive sensing --- quantum finite automata --- periodic languages --- confidence amplification --- photodetection
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Quantum optics has received a lot of attention in recent decades due to the handiness and versatility of optical systems, which have been exploited both to study the foundations of quantum mechanics and for various applications. In this Special Issue, we collect some articles and a review focusing on some research activities that show the potential of quantum optics in the advancement of quantum technologies.
Research & information: general --- Physics --- integrated photonics --- quantum optics --- quantum simulation --- mesoscopic quantum states of light --- nonclassical photon-number correlations --- lossy transmission channels --- quantum state engineering --- nonlinear interferometer --- spontaneous four-wave mixing --- quantum message authentication --- quantum three-pass protocol --- Gao’s forgery --- swap test --- conditional states --- silicon photomultipliers --- optical cross-talk --- nonclassicality --- quantum imaging --- plenoptic imaging --- quantum correlations --- SPAD arrays --- quantum fisher information --- compressive sensing --- quantum finite automata --- periodic languages --- confidence amplification --- photodetection --- n/a --- Gao's forgery
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