Joint Imaging Across Multiple Beams

Phased array technology provides the capability to form multiple beams simultaneously. This can be used to significantly enhance the field-of-view of radio astronomical instruments as demonstrated by the recent upgrade of the Westerbork Synthesis Radio Telescope and the Australian Square Kilometre Array (SKA) Pathfinder (ASKAP). At the moment, the data associated with each beam are treated as a separate observation. In this paper, an extension of facet based imaging is presented that produces a single image for the combined field-of-view of all beams. The proposed method is illustrated using simulations for a linear array composed of multiple subarrays with multi-beaming capability. As this approach significantly reduces the size of the sub-images to be made for each individual beam, it may significantly reduce the compute costs of image reconstruction for the combined field-of-view of all beams.

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