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Synthetic Aperture Radar Image Formation with Uncertainty Quantification [article]

Victor Churchill, Anne Gelb
2020 arXiv   pre-print
Synthetic aperture radar (SAR) is a day or night any-weather imaging modality that is an important tool in remote sensing.  ...  Samples of the resulting posterior as well as parameters governing speckle and noise are obtained using a Gibbs sampler.  ...  Note later estimating the associated speckle parameter α−1 through that by using the discrete Fourier transform in (1) we introduce sampling rather than post-image-formation techniques.  ... 
arXiv:2007.06380v1 fatcat:qc4bio3oijgybem2iqe6dnk574

IMAGE DENOISING USING WAVELET AND SHEARLET TRANSFORM

Bharath Kumar S, Kavyashree, Ananth V Naik, Kavyashree C.L, Gayathri K.M
2017 International journal of research - granthaalayah  
Wavelet transforms are one of the denoising algorithms used as conventional methods.  ...  The various types of noise patterns observed in the image are Gaussian, salt and pepper, speckle etc. due to which the image is attenuated or amplified.  ...  Figure ( 2) represents the histogram graph of salt and pepper noise.  Speckle noise: Speckle noise is a granular noise which degrades the quality of the active radar, synthetic aperture radar (SAR), medical  ... 
doi:10.29121/granthaalayah.v5.i4raceee.2017.3316 fatcat:yqev53w27rgwznaccwuxfwqvmu

Image Denoising Using Wavelet And Shearlet Transform

Bharath Kumar S, Kavyashree S, Ananth V Naik, Kavyashree C.L, Gayathri K.M
2017 Zenodo  
Wavelet transforms are one of the denoising algorithms used as conventional methods.  ...  The various types of noise patterns observed in the image are Gaussian, salt and pepper, speckle etc. due to which the image is attenuated or amplified.  ...  Figure ( 2) represents the histogram graph of salt and pepper noise.  Speckle noise: Speckle noise is a granular noise which degrades the quality of the active radar, synthetic aperture radar (SAR), medical  ... 
doi:10.5281/zenodo.580617 fatcat:n2jem6ehaban7kv6m5tkvnmgbi

Co-registration and complex interpolation

Dominique Derauw, Stephane Roose, Giorgio Franceschetti, Christopher J. Oliver, James C. Shiue, Shahram Tajbakhsh
1995 Synthetic Aperture Radar and Passive Microwave Sensing  
The method allows also complex interpolation of an entire image, by application, at each point, of a bilinear co-ordinate transformation.  ...  This paper presents a novel and efficient method, based on a modified version of the Chirp-Z transform algorithm, for performing the co-registration of SAR images as required in SAR interferometry.  ...  In a first step we compute the discrete Fourier transform U(k∆f x ) of a given discrete sequence u(n∆x) (our original SAR image).  ... 
doi:10.1117/12.227142 fatcat:x7k47urz2jgevatq2x6wqhgppi

Demonstrated resolution enhancement capability of a stripmap holographic aperture ladar system

Samuel M. Venable, Bradley D. Duncan, Matthew P. Dierking, David J. Rabb
2012 Applied Optics  
Holographic aperture ladar (HAL) is a variant of synthetic aperture ladar (SAL).  ...  By then taking the Fourier transform of the synthetic image intensity and examining the fundamental spatial frequency content, we were able to produce experimental modulation transfer function curves which  ...  formed via discrete Fourier transform.  ... 
doi:10.1364/ao.51.005531 pmid:22859045 fatcat:6c4ccm4tgvbjjcfecpo2yfvlgi

Image De-noising by Various Filters for Different Noise

Pawan Patidar, Manoj Gupta, Sumit Srivastava, Ashok Kumar Nagawat
2010 International Journal of Computer Applications  
Wavelet transforms have become a very powerful tool for de-noising an image.  ...  Image processing is basically the use of computer algorithms to perform image processing on digital images. Digital image processing is a part of digital signal processing.  ...  Speckle noise Speckle noise is a granular noise that inherently exists in and degrades the quality of the active radar and synthetic aperture radar (SAR) images.  ... 
doi:10.5120/1370-1846 fatcat:x6wu4mxtebep5blb6olf27d33u

Image Denoising Based on Wavelet Analysis for Satellite Imagery [chapter]

Parthasarathy Subashini, Marimuthu Krishnaveni
2012 Advances in Wavelet Theory and Their Applications in Engineering, Physics and Technology  
Synthetic aperture radar is a radar technology that is used from satellite or airplane (Lee,Jukervish 1994) .  ...  Coherent processing of synthetic aperture radar (SAR) data makes images susceptible to speckles (Lee,Jukervish 1994) .  ... 
doi:10.5772/36140 fatcat:peb56kehereajkjpp3ieixw3xy

Bistatic Radar Imaging of the Marine Environment—Part II: Simulation and Results Analysis

A. Arnold-Bos, A. Khenchaf, A. Martin
2007 IEEE Transactions on Geoscience and Remote Sensing  
The pseudo raw, temporal signals delivered by MaRS are further processed using, for instance, bistatic synthetic aperture beamforming.  ...  We present a bistatic, polarimetric and real aperture Marine Radar Simulator (MaRS) producing pseudo-raw radar signal.  ...  synthetic aperture or real aperture radar) is less clear.  ... 
doi:10.1109/tgrs.2007.899812 fatcat:kp4p3wlkxzapdpjhft3vb4btoi

Performance Comparison of Various Filters and Wavelet Transform for Image De-Noising

Chanchal Srivastava Chanchal Srivastava
2013 IOSR Journal of Computer Engineering  
This paper proves that Wavelet Transform method is very effective for all types of noise. Results of this paper have been simulated on MATLAB.  ...  Digital images are prone to a variety of noise. The varieties include Speckle noise, Gaussian noise, Salt and pepper noise.  ...  Speckle Noise Speckle noise is a granular noise that inherently exists in and degrades the quality of the active radar and synthetic aperture radar (SAR) images.  ... 
doi:10.9790/0661-01015563 fatcat:cagky4qjinewrhnk632etjkyfa

On the Superresolution Capacity of Imagers Using Unknown Speckle Illuminations

Jerome Idier, Simon Labouesse, Marc Allain, Penghuan Liu, Sebastien Bourguignon, Anne Sentenac
2018 IEEE Transactions on Computational Imaging  
This theoretical result is important for many practical imaging systems such as acoustic and electromagnetic tomographs, fluorescence and photoacoustic microscopes, or synthetic aperture radar imaging.  ...  Speckle based imaging consists of forming a super-resolved reconstruction of an unknown sample from low-resolution images obtained under random inhomogeneous illuminations (speckles).  ...  This idea is at the core of many imaging configurations such as Synthetic Aperture Radar (SAR) [2] , diffraction tomography [5] , and Structured Illumination fluorescence Microscopy (SIM) [6] , [7]  ... 
doi:10.1109/tci.2017.2771729 fatcat:kp62r5hiqjctbchfldwhaczn64

A Novel Algorithm for Ship Detection in SAR Imagery Based on the Wavelet Transform

M. Tello, C. Lopez-Martinez, J.J. Mallorqui
2005 IEEE Geoscience and Remote Sensing Letters  
Index Terms-Multiresolution analysis, ship detection, synthetic aperture radar (SAR) imagery, wavelet transform.  ...  On the contrary, satellite-based synthetic aperture radar (SAR) provides a powerful surveillance capability allowing the observation of broad expanses, independently from weather effects and from the day  ...  ACKNOWLEDGMENT The authors would like to thank the responsibles of DE-CLIMS project for providing access to the database of SAR images with groundtruth and to H. Greidanus for his helpful comments.  ... 
doi:10.1109/lgrs.2005.845033 fatcat:efm3pek5vngodlgyjjnn7vvrvm

A Review on Image Denoising Techniques

Smita Vasant Tempe
2021 International Journal for Research in Applied Science and Engineering Technology  
Unlike previous approaches, such as curvelets, which generate a transform in the continuous domain and then discretize for sampled data, we begin with a discrete-domain construction and then investigate  ...  We use nonseparable filter banks to create a discrete-domain multiresolution and multidirection expansion, similar to how wavelets are produced from filter banks.  ...  The Synthetic Aperture Radar picture and aerial photographs both include a lot of speckle noise.  ... 
doi:10.22214/ijraset.2021.39342 fatcat:yww3auo2qnbaveiswkyibul73m

On the Underside Scarring of Floating Ice Sheets

G.J. Musil
1989 Annals of Glaciology  
Detailed analysis of radar images, obtained using a synthetic aperture radar technique, from the bottom surface of a floating ice sheet suggests the presence of linear, groove-type scarring.  ...  It therefore seems probable that the roughness parameters, measured on Ross Ice Shelf using standard radio-echo techniques, relate to linear grooves which were introduced in the region of ice grounding  ...  Doake for allowing me to use the results of their SAR survey on Alexander Island. I am also indebted to Dr I. Allison and Dr K.  ... 
doi:10.1017/s0260305500007060 fatcat:myanwphvr5b45ohdb6qxldmyky

The Curvelet Approach for Denoising in various Imaging Modalities using Different Shrinkage Rules

D. Mary sugantharathnam, Dr. D. Manimegalai
2011 International Journal of Computer Applications  
Two digital implementations of the Curvelet transform (a multiscale transform) viz the Unequally Spaced Fast Fourier Transform (USFFT) and the Wrapping Algorithm are used to de-noise images degraded by  ...  The images usually bring different kinds of noise in the process of receiving, coding and transmission. In this paper the Curvelet transform is used for de-noising of image.  ...  Speckle noise It is a granular noise that inherently exists in and degrades the quality of the active radar and Synthetic Aperture Radar images.  ... 
doi:10.5120/3575-4933 fatcat:ztfyxritavhezi6d2ittxq7kf4

Performance Analysis Survey of Various SAR Image Despeckling Techniques

A. Rajamani, V. Krishnaveni
2014 International Journal of Computer Applications  
Over the past four decades, the Synthetic Aperture Radar (SAR) imagery has become a beneficial and important application over the optical satellite imagery because of its ability to operate in any weather  ...  Thus, it has become essential to remove this speckle noise using suitable techniques.  ...  INTRODUCTION The Synthetic Aperture Radar (SAR) is very useful for providing information about earth's surface by using the relative motion between antenna and its target.  ... 
doi:10.5120/15584-4254 fatcat:ld7hmft4cbeqje2conp3eroojm
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