Abstract
Linear image deconvolution for radio-astronomy is an ill-posed problem. For this reason, a-priori knowledge is crucial for improving the performance of the deconvolution. In this paper we show that combining non-negativity constraints with an upper bound on the magnitude of each pixel in the image can significantly improve the image formation algorithm. We also show that the minimum variance distortionless response (MVDR) dirty image provides the tightest upper bound out of all beamformers. We then show how the LS-MVI image formation algorithm can be reformulated as a preconditioned weighted least squares algorithm. The resulting algorithm can be efficiently solved using the active-set method. The performance of the algorithm is demonstrated in simulation and compared with constrained least squares based on the classical dirty image.
Original language | English |
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Title of host publication | 2015 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2015 - Proceedings |
Publisher | Institute of Electrical and Electronics Engineers Inc. |
Pages | 5664-5668 |
Number of pages | 5 |
ISBN (Electronic) | 9781467369978 |
DOIs | |
State | Published - 4 Aug 2015 |
Externally published | Yes |
Event | 40th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2015 - Brisbane, Australia Duration: 19 Apr 2014 → 24 Apr 2014 |
Publication series
Name | ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings |
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Volume | 2015-August |
ISSN (Print) | 1520-6149 |
Conference
Conference | 40th IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2015 |
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Country/Territory | Australia |
City | Brisbane |
Period | 19/04/14 → 24/04/14 |
Bibliographical note
Publisher Copyright:© 2015 IEEE.
Keywords
- Krylov subspace
- LSQR
- MVDR
- Radio astronomy
- array signal processing
- constrained optimization
- image deconvolution