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Compressed sensing and radio interferometry
2015 23rd European Signal Processing Conference (EUSIPCO), 2015Radio interferometric imaging constitutes a strong ill-posed inverse problem. In addition, the next generation radio telescopes, such as the Low Frequency Array (LOFAR) and the Square Kilometre Array (SKA), come with an additional direction-dependent effects which impacts the image restoration.
M. Jiang +4 more
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Radio Frequency Interference: Simulations for Radio Interferometry Arrays
, 2021 Radio Frequency Interference (RFI) is a massive problem for radio observatories around the world. Due to the growth of telecommunications and air travel RFI is increasing exactly when the world's radio telescopes are increasing significantly in sensitivity, making RFI one of the most pressing problems for astronomy in the era of the Square Kilometre ...
Finlay, Chris
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Reviews of Geophysics, 1987
The potential of Very Long Baseline Interferometry (VLBI) to provide important new geodetic, geophysical, and astrometric information has long been recognized, and the past four years have seen a realization of that potential. VLBI measurements have been used to determine the sizes, shapes, rotations, flexures and tectonic deformations of networks of ...
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The potential of Very Long Baseline Interferometry (VLBI) to provide important new geodetic, geophysical, and astrometric information has long been recognized, and the past four years have seen a realization of that potential. VLBI measurements have been used to determine the sizes, shapes, rotations, flexures and tectonic deformations of networks of ...
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Precision Geodesy via Radio Interferometry
Science, 1972Very-long-baseline interferometry experiments, involving observations of extragalactic radio sources, were performed in 1969 to determine the vector separations between antenna sites in Massachusetts and West Virginia. The 845.130-kilometer baseline was estimated from two separate experiments.
H F, Hinteregger +9 more
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Reviews of Geophysics, 1983
In the previous Quadrennial Report, Clark [1979c] concluded that, after slightly more than one decade of development and refinement, the technique of Very Long Baseline Interferometry (VLBI) had “come of age.” However, by the close of 1978, only the most tentative first steps had been taken by the geodetic community toward the deployment and operation ...
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In the previous Quadrennial Report, Clark [1979c] concluded that, after slightly more than one decade of development and refinement, the technique of Very Long Baseline Interferometry (VLBI) had “come of age.” However, by the close of 1978, only the most tentative first steps had been taken by the geodetic community toward the deployment and operation ...
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Positioning of Geostationary Satellite by Radio Interferometry
IEEE Transactions on Aerospace and Electronic Systems, 2019There are several perturbations that force the satellite orbit to deviate from the elliptical form. To cope with these perturbations, station keeping is applied. For accurate station keeping, determination of the true satellite orbit is necessary. Radio interferometry is one of the techniques used for determining azimuth and elevation look angles of a ...
Mohammad Sadeghi +2 more
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Radio-frequency low-coherence interferometry
Optics Letters, 2014A method for retrieving low-coherence interferograms, based on the use of a microwave photonics filter, is proposed and demonstrated. The method is equivalent to the double-interferometer technique, with the scanning interferometer replaced by an analog fiber-optics link and the visibility recorded as the amplitude of its radio-frequency (RF) response.
Carlos R, Fernández-Pousa +3 more
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Regularization methods in radio interferometry
Radiophysics and Quantum Electronics, 2007The problem of image retrieval in radio interferometry is a classical example of an ill-posed problem. In this paper, we consider a new approach to the radio-interferometric imaging based on regularization, which is computationally more flexible. A new type of a weighting function suitable for managing the interferometer antenna pattern is obtained ...
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Angular Position Determination of Spacecraft by Radio Interferometry
Proceedings of the IEEE, 2007This paper describes a variety of interferometric techniques that may be used for measuring the angular location of a spacecraft with respect to natural celestial radio sources or another spacecraft. The differential propagation time-delay techniques largely cancel the common error sources and normally achieve low angular coordinate errors.
Gabor Lanyi +2 more
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