Progression of Digital-Receiver Architecture: From MWA to SKA1-Low,and beyond

TL;DR

This paper reviews the evolution of digital-receiver architectures in radio astronomy, focusing on the progression from MWA to SKA1-Low, highlighting technological advances and future directions in digital signal processing systems.

Contribution

It provides a comprehensive overview of technological developments in digital-receiver architectures for aperture arrays, emphasizing innovations from MWA to SKA1-Low and future RFSoC-based systems.

Findings

Advances in ADCs, FPGAs, and CPU-GPU platforms have enabled more efficient signal processing.

Pathfinder telescopes have provided valuable feedback for SKA development.

Future designs will incorporate RFSoC technology for improved performance.

Abstract

Backed by advances in digital electronics, signal processing, computation, and storage technologies, aperture arrays, which had strongly influenced the design of telescopes in the early years of radio astronomy, have made a comeback. Amid all these developments, an international effort to design and build the world's largest radio telescope, the Square Kilometre Array (SKA), is ongoing. With its vast collecting area of 1 sq-km, the SKA is envisaged to provide unsurpassed sensitivity and leverage technological advances to implement a complex receiver to provide a large field of view through multiple beams on the sky. Many pathfinders and precursor aperture array telescopes for the SKA, operating in the frequency range of 10-300 MHz, have been constructed and operationalized to obtain valuable feedback on scientific, instrumental, and functional aspects. This review article looks explicitly into the progression of digital-receiver architecture from the Murchison Widefield Array (precursor) to the SKA1-Low. It highlights the technological advances in analog-to-digital converters (ADCs),field-programmable gate arrays (FPGAs), and central processing unit-graphics processing unit (CPU-GPU) hybrid platforms around which complex digital signal processing systems implement efficient channelizers, beamformers, and correlators. The article concludes with a preview of the design of a new generation signal processing platform based on radio frequency system-on-chip (RFSoC).