Joint deconvolution and semi and unsupervised component separation, with application to radio-interferometry
Description
With the development of continent-wide radio telescopes, the analysis of multi-frequency radio-interferometric data has become a significant challenge in signal processing and astrophysics. In this respect, component separation methods are an adequate tool as they allow to separate multi-frequency data into elementary physical components. However, standard component separation algorithms are not adapted to radio-interferometric data for several reasons: (i) they are constituted of incomplete measurements in the Fourier domain, also known as the visibility domain, and are potentially further deteriorated by instrumental or non-coplanar effects, and (ii) the sought-after signals can be severely drowned in noise or other emissions. Consequently, accounting for the telescope instrumental response requires developing dedicated algorithms to solve a joint deconvolution and separation problem. Furthermore, the recovery of weak signals calls for the design of accurate approaches that make use of physical models known a priori; this motivates the development of semi-supervised separation methods that integrate machine learning techniques. (author)
Abstract (French)
Avec le developpement des radiotelescopes de taille continentale, l'analyse des donnees radio-interferometriques multifrequences devient un enjeu majeur tant en traitement du signal qu'en astrophysique. A cet egard, les methodes de separation de composantes constituent un outil adequat car elles permettent de separer les donnees multifrequences en composantes physiques elementaires. Cependant, les algorithmes standard de separation de composantes ne sont pas adaptes aux donnees radio-interferometriques a plus d'un titre: (i) celles-ci sont composees de mesures incompletes dans le domaine de Fourier, dit des visibilites, et sont en outre potentiellement deteriorees par des effets instrumentaux ou non coplanaires, et (ii) les signaux recherches peuvent etre severement noyes dans le bruit ou dans d'autres emissions. En consequence, la prise en compte de la reponse instrumentale des telescopes requiert le developpement d'algorithmes dedies pour resoudre un probleme de separation et de deconvolution conjoint. De plus, la recuperation de signaux faibles necessite la conception d'approches precises qui exploitent des modeles physiques connus a priori; cela motive le developpement de methodes de separation semi supervisees qui integrent des techniques par apprentissage automatique
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Additional details
Additional titles
- Original title (English)
- Separation de composantes semi et non supervisee et deconvolution conjointe, application a la radio-inteferometrie
Publishing Information
- Imprint Pagination
- 189 p.
- Report number
- FRCEA-TH--14868
INIS
- Country of Publication
- France
- Country of Input or Organization
- France
- INIS RN
- 54015226
- Subject category
- S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
- Resource subtype / Literary indicator
- Thesis
- Descriptors DEI
- ALGORITHMS; ASTROPHYSICS; INTERFEROMETRY; TELESCOPES
- Descriptors DEC
- MATHEMATICAL LOGIC; PHYSICS
Optional Information
- Notes
- 104 refs.; Available from the INIS Liaison Officer for France, see the INIS website for current contact and E-mail addresses