Radio-astronomical imaging on graphics processors

Abstract

Abstract Realizing the next generation of radio telescopes such as the Square Kilometre Array (SKA) requires both more efficient hardware and algorithms than today’s technology provides. The image-domain gridding (IDG) algorithm is a novel approach towards solving the most compute-intensive parts of creating sky images: gridding and degridding. It alleviates the performance bottlenecks of traditional AW-projection gridding by applying instrumental and environmental corrections in the image domain instead of in the Fourier domain. In this paper, we present a thorough performance analysis of this algorithm for an Intel Xeon CPU, Intel Xeon Phi, and GPUs from AMD and NVIDIA. We show that, by evaluating trigonometric functions in hardware, GPUs are both much faster and more energy efficient than a CPU or Xeon Phi. Furthermore, on GPUs, IDG is an order of magnitude faster and more energy efficient than traditional AW-projection. IDG on GPUs is the ideal candidate imaging technique for the SKA, as it meets the computational and energy constraints of the SKA Science Data Processor system.