Restoration of radio images of non-coherent radio sources, based on the measured visibility function

A new multi-circle method of radio image restoration of radio sources, based on the measured radiointerferometric visibility function, is proposed. The algorithm of the determination of the number of circles, their angular diameter and flux density, based on Fourier-Bessel series, is shown. The radio image of Cas A is restored from measurements of this source. These measurements were performed using the short-baseline (up to 2000 D//spl lambda/) interferometer URAN-3. A model of the large-scale structure, deduced from measurements in the meter wave band, is inconsistent with the results obtained at decameter wavelengths.