Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    Measuring phased-array antenna beampatterns with high dynamic range for the Murchison Widefield Array using 137MHz ORBCOMM satellites

    232253_232253.pdf (2.349Mb)
    Access Status
    Open access
    Authors
    Neben, A.
    Bradley, R.
    Hewitt, J.
    Bernardi, G.
    Bowman, J.
    Briggs, F.
    Cappallo, R.
    Deshpande, A.
    Goeke, R.
    Greenhill, L.
    Hazelton, B.
    Johnston-Hollitt, M.
    Kaplan, D.
    Lonsdale, C.
    Mcwhirter, S.
    Mitchell, D.
    Morales, M.
    Morgan, E.
    Oberoi, D.
    Ord, S.
    Prabu, T.
    Shankar, N.
    Srivani, K.
    Subrahmanyan, R.
    Tingay, Steven
    Wayth, Randall
    Webster, R.
    Williams, A.
    Williams, C.
    Date
    2015
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Neben, A. and Bradley, R. and Hewitt, J. and Bernardi, G. and Bowman, J. and Briggs, F. and Cappallo, R. et al. 2015. Measuring phased-array antenna beampatterns with high dynamic range for the Murchison Widefield Array using 137MHz ORBCOMM satellites. Radio Science. 50 (7): pp. 614-629.
    Source Title
    Radio Science
    DOI
    10.1002/2015RS005678
    ISSN
    0048-6604
    School
    Curtin Institute of Radio Astronomy (Physics)
    Remarks

    Copyright © 2015 American Geophysical Union. Reproduced by permission.

    URI
    http://hdl.handle.net/20.500.11937/47008
    Collection
    • Curtin Research Publications
    Abstract

    Detection of the fluctuations in a 21 cm line emission from neutral hydrogen during the Epoch of Reionization in thousand hour integrations poses stringent requirements on calibration and image quality, both of which necessitate accurate primary beam models. The Murchison Widefield Array (MWA) uses phased-array antenna elements which maximize collecting area at the cost of complexity. To quantify their performance, we have developed a novel beam measurement system using the 137 MHz ORBCOMM satellite constellation and a reference dipole antenna. Using power ratio measurements, we measure the in situ beampattern of the MWA antenna tile relative to that of the reference antenna, canceling the variation of satellite flux or polarization with time. We employ angular averaging to mitigate multipath effects (ground scattering) and assess environmental systematics with a null experiment in which the MWA tile is replaced with a second-reference dipole. We achieve beam measurements over 30 dB dynamic range in beam sensitivity over a large field of view (65% of the visible sky), far wider and deeper than drift scans through astronomical sources allow. We verify an analytic model of the MWA tile at this frequency within a few percent statistical scatter within the full width at half maximum. Toward the edges of the main lobe and in the sidelobes, we measure tens of percent systematic deviations. We compare these errors with those expected from known beamforming errors.

    Related items

    Showing items related by title, author, creator and subject.

    • System design for the square kilometre array : new views of the universe
      Colegate, Timothy Maarten (2012)
      The Square Kilometre Array (SKA) radio telescope is being designed as a premier scientific instrument of the 21st century, using novel technologies to maximise its scientific capability. The SKA has an aggressive project ...
    • Beam-forming errors in Murchison Widefield array phased array antennas and their effects on epoch of reionization science
      Neben, A.; Hewitt, J.; Bradley, R.; Dillon, J.; Bernardi, G.; Bowman, J.; Briggs, F.; Cappallo, R.; Corey, B.; Deshpande, A.; Goeke, R.; Greenhill, L.; Hazelton, B.; Johnston-Hollitt, M.; Kaplan, D.; Lonsdale, C.; McWhirter, S.; Mitchell, D.; Morales, M.; Morgan, E.; Oberoi, D.; Ord, S.; Prabu, T.; Shankar, N.; Srivani, K.; Subrahmanyan, R.; Tingay, Steven; Wayth, Randall; Webster, R.; Williams, A.; Williams, C. (2016)
      Accurate antenna beam models are critical for radio observations aiming to isolate the redshifted 21 cm spectral line emission from the Dark Ages and the Epoch of Reionization (EOR) and unlock the scientific potential of ...
    • Measuring phased-array antenna beampatterns with high dynamic range for the Murchison Widefield Array using 137MHz ORBCOMM satellites
      Neben, A.; Bradley, R.; Hewitt, J.; Bernardi, G.; Bowman, J.; Briggs, F.; Cappallo, R.; Deshpande, A.; Goeke, R.; Greenhill, L.; Hazelton, B.; Johnston-Hollitt, M.; Kaplan, D.; Lonsdale, C.; McWhirter, S.; Mitchell, D.; Morales, M.; Morgan, E.; Oberoi, D.; Ord, Stephen; Prabu, T.; Shankar, N.; Srivani, K.; Subrahmanyan, R.; Tingay, Steven; Wayth, Randall; Webster, R.; Williams, A.; Williams, C. (2015)
      Detection of the fluctuations in a 21cm line emission from neutral hydrogen during the Epoch of Reionization in thousand hour integrations poses stringent requirements on calibration and image quality, both of which ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.