The MWA consists of 2048 dual-polarization dipole antennas optimized for the 80-300 MHz frequency range, arranged as 128 "tiles", each a 4x4 array of dipoles. A complete technical description of the telescope is given in the journal article: The Murchison Widefield Array: The SKA Low Frequency Precursor by Tingay et al. (2013).
The array has no moving parts, and all telescope functions including pointing are performed by electronic manipulation of dipole signals, each of which contains information from nearly four steradians of sky centered on the zenith. Each tile performs an analog beamforming operation, narrowing the field of view to a fully steerable 25 degrees at 150 MHz.
The majority of the tiles (112) are scattered across a roughly 1.5 km core region, forming an array with very high imaging quality, and a field of view of several hundred square degrees at a resolution of several arcminutes. The remaining 16 tiles are placed at locations outside the core, yielding baseline distances of about 3 km to allow higher angular resolution for solar burst measurements.
Aerial photo of the central region on of the MWA
Summary of MWA properties
|Frequency range||80 - 300 MHz|
|Number of receptors||2048 dual polarization dipoles|
|Number of antenna tiles||128|
|Number of baselines||8128|
|Collecting area||Approx. 2000 sq. meters|
|Field of view||Approx. 15 - 50 deg. (200 - 2500 sq. deg.)|
|Instantaneous bandwidth||30.72 MHz|
|Spectral resolution||40 kHz|
|Temporal resolution||0.5 seconds|
|Polarization||Full Stokes (I, Q, U, V)|
|Array configuration||50 antenna tiles within 100 meters
62 antenna tiles between 100 and 750 meters
16 antenna tiles at 1500 meters
The MWA is located within the Murchison Radioastronomy Observatory (MRO) in the Shire of Murchison in Western Australia (WA).
The MWA site is over 200 km inland from the western Australian coast, and approximately 300 km from the small coastal city of Geraldton which lies a few hundred kilometers north of Perth. The target region is extremely sparsely populated, and is characterized by fairly flat, sparsely vegetated, semi-arid terrain criss-crossed by shallow washes and watercourses.
Particular strengths of the Murchison area for siting the MWA include excellent sky access, with the Galactic Center and the Magellanic Clouds reaching high elevations, and extremely low levels of RFI.
In addition to the MWA, the MRO is home to the Australian SKA Pathfinder (ASKAP) and will be the site for the international Square Kilometer Array (SKA) low frequency telescope.