The Murchison Widefield Array Correlator

TL;DR

The paper describes the design and implementation of the Murchison Widefield Array correlator, a hybrid hardware-software system that processes large-scale radio astronomy data in real-time for the SKA precursor.

Contribution

It introduces a novel hybrid FPGA-GPU correlator architecture optimized for high-throughput radio astronomy data processing.

Findings

Correlator achieves approximately 8 TFLOPS processing capability.

Generates 8.3 TB/day of correlation data in real-time.

Data is transferred 700 km for storage and analysis.

Abstract

The Murchison Widefield Array (MWA) is a Square Kilometre Array (SKA) Precursor. The telescope is located at the Murchison Radio--astronomy Observatory (MRO) in Western Australia (WA). The MWA consists of 4096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256 inputs. A hybrid approach to the correlation task is employed, with some processing stages being performed by bespoke hardware, based on Field Programmable Gate Arrays (FPGAs), and others by Graphics Processing Units (GPUs) housed in general purpose rack mounted servers. The correlation capability required is approximately 8 TFLOPS (Tera FLoating point Operations Per Second). The MWA has commenced operations and the correlator is generating 8.3 TB/day of correlation products, that are subsequently transferred 700 km from the MRO to Perth (WA) in real-time for storage and offline processing. In this paper we outline the correlator design, signal path, and processing elements and present the data format for the internal and external interfaces.