Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry

Details Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry

Jul 1984

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1984aj.....89.1076s&link_type=abstract

Astronomical Journal (ISSN 0004-6256), vol. 89, July 1984, p. 1076-1081.

Astronomy and Astrophysics

Astronomy

67

Calibrating, Low Frequencies, Radio Astronomy, Radio Interferometers, Correlation, Interpolation, Penalty Function

Scientific paper

A fundamental assumption of the self-calibration/hybrid mapping techniques, which are in widespread use in aperture synthesis data reduction, is one of isoplanatism: that over any given element of the array, all incident wave fronts, regardless of their directions of arrival, are subject to the same tropospheric/ionospheric path delays. This a poor assumption in the case of a low-frequency array (operating at frequencies lower than approximately 300 MHz), because of the large field of view of such an instrument and because of the wavelength dependence of wave-front perturbation by the ionosphere. The isoplanatism assumption may be relaxed by incorporating an interpolation formula in the solution for antenna/IF phases, and the usual mapping/deconvolution techniques then must be modified in order to cope with space-variant effects. Because of the consequent increase in the number of solution parameters, a better source model, higher signal-to-noise ratio, and a larger number of array elements (than are ordinarily required in order to self-calibrate) become desirable.

Affiliated with

Also associated with

No associations

Rating

Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relaxing the isoplanatism assumption in self-calibration; applications to low-frequency radio interferometry will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1704225