Low-Frequency Aperture Array


Low-Frequency Aperture Array


The “Low-Frequency Aperture Array” (LFAA) element is the set of antennas, on board amplifiers and local processing required for the Aperture Array telescope of the SKA. LFAA includes the design of the local station signal processing and hardware required to combine the antennas and the transport of antenna data to the station processing. The local monitoring & control including the software of the aperture array are included. LFAA includes the different types of stations necessary as defined by the baseline reference design.

No moving parts are used in the LFAA, it being a true all-electronic telescope, based on stationary antennas and having a capability enabled by advanced signal processing and computing, the capacity of which grows with time“, says Professor Peter Hall, LFAA Consortium Project Scientist, Curtin University, Perth, Australia.

The Low Frequency Aperture Array will explore the edge of the Universe where matter that everything is made of emerged out of the plasma of the Big Bang“, says Dr. Andrew Faulkner, LFAA Consortium Project Engineer, Cambridge University, UK.

More about the LFAA
The Low-Frequency Aperture Array (LFAA) covers the lowest frequency band for the SKA, from 50MHz up to 350MHz in the Baseline Design. It is an aperture array consisting of over a quarter of a million wide bandwidth antennas of a single design. The configuration is very close packed with 75% of the antennas within a 2km diameter core and the remaining collecting area situated on three spiral arms, extending out to a radius of 50km and enabling higher spatial resolution observations.

Main Challenges
The main challenges facing the LFAA consortium team are sheer scale. With millions of antenna all having to be built to the same specification, the testing will need to be rigorous to ensure longevity in the design. Not only the antenna fall under their remit, but the ability to combine and transfer the data to local stations, which will require robust architecture.

The LOFAR array is one success story of the LFAA consortium team members

The LOFAR Telescope Array (c) ASTRON













Background of the LFAA Consortium

Computer generated visualisation of SKA-low

Artist Impression of dipole antenna – Swinburne Astronomy Productions/ICRAR/U. Cambridge/ASTRON.

Partners in this consortium designed, realised and operate SKA pathfinder and precursor low frequency array telescopes such as LOFAR, the Low Frequency Array and MWA (Murchison Widefield Array).

LOFAR is a large Aperture Array telescope with electronic beam steering consisting of 45 stations. The core of LOFAR and the majority of the stations has been realised in the Netherlands. Long baselines are created with stations in Germany, France, the UK and Sweden. With a total of 40.000 antennas LOFAR is currently one of the largest arrays in the world.

MWA is a low frequency telescope, similar in concept as LOFAR, realised near the Australian SKA site. Although smaller in size, 2048 antennas and more compact, MWA provides attractive properties by means of correlating all 128 tiles (each tile=16 antennas).

The MWA will also provide a test bed for early prototypes to facilitate test and verification.

With the LOFAR experience, a large low frequency system, and the MWA experience, a system on the SKA site, the LFAA consortium has the relevant experience for the design and realisation of the LFAA Element.

The consortium is led by Jan Geralt Bij de Vaate and is made up of 11 institutions around the globe

Institutes involved in the LFAA Consortia include:

To find out more about each member of the consortium click on the map below

SKA Global Consortia