Radio astronomy image enhancement in the presence of phase errors using genetic algorithms

Modern radio astronomy interferometric telescopes use Earth rotation aperture synthesis imaging techniques. New projects for radio telescopes include hundreds and thousands of elements and presume multibeam and snapshot imaging. Each element, or base station, in its turn is a phase-array antenna. Phase instabilities due to instrumentation and atmospheric phase variations can ruin the synthesized image. There is a need to calibrate both the base stations and the whole interferometric configuration. A method of image enhancement of a calibration radio source, in the presence of phase errors, using genetic algorithm optimization techniques is described. Image sharpness is chosen as a cost function in the process of optimization. Computer simulations show the considerable positive effects in both applications.