Abstract

High sensitivity imaging at low radio frequencies require wideband receivers and long baselines. This, in combination with inherently stronger and more complex sky brightness, translates to a requirement of high dynamic range imaging using vast quantities of data. Additionally, wide field of view also requires accounting for many time- and frequencydependent instrumental effects to achieve thermal noise limited images. These effects are in general also directionally dependent (DD) and require use of advanced imaging algorithms which are inherently also more compute intensive.

This paper gives an overview of the status of the projection algorithms to correct for the DD effects due to the antenna primary beam (BP) and demonstrate the improvements in imaging performance afforded by these new algorithms. Larger data volume and need for more computeexpensive imaging algorithms couples algorithm design and High Performance Computing (HPC) techniques. This is a major challenge, particularly in low frequency imaging. We briefly mention some of the HPC solutions being currently pursued in the community.