
Calibration of Siberian Radioheliograph antenna gains using redundancy
Author(s) -
Мария Глоба,
Sergey Lesovoi
Publication year - 2021
Publication title -
solnečno-zemnaâ fizika
Language(s) - English
Resource type - Journals
ISSN - 2712-9640
DOI - 10.12737/szf-74202111
Subject(s) - redundancy (engineering) , calibration , computer science , amplitude , antenna (radio) , acoustics , electronic engineering , optics , physics , engineering , telecommunications , quantum mechanics , operating system
The paper describes application of standard gain calibration using redundancy for a 48-antenna prototype of Siberian Radioheliograph. Traditionally, for calibration, the visibilities were measured only between adjacent antennas since they have the highest signal-to-noise ratio and are sufficient for phase calibration. We have shown that this limited set of visibilities did not allow using the antenna array redundancy potential and obtaining images with a high dynamic range on a permanent basis. Images without amplitude calibration contain many artifacts and require special care when analyzed. The inclusion of visibility measurement between antennas with a double step made it possible to significantly increase the accuracy of solving the system of equations for amplitudes. Images constructed using both phase and amplitude calibrations do not have visible artifacts and are more reliable.