Beam Maps of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Measured With a Drone
We present beam measurements of the CHIME telescope using a radio calibration source deployed on a drone payload. During test flights, the pulsing calibration source and the telescope were synchronized to GPS time, enabling in-situ background subtraction for the full <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$N^{2}$ </tex-math></inline-formula> visibility matrix for one CHIME cylindrical reflector. We use the autocorrelation products to estimate the primary beam width and centroid location, and compare these quantities to solar transit measurements and holographic measurements where they overlap on the sky. We find that the drone, solar, and holography data have similar beam parameter evolution across frequency and both spatial coordinates. This paper presents the first drone-based beam measurement of a large cylindrical radio interferometer. Furthermore, the unique analysis and instrumentation described in this paper lays the foundation for near-field measurements of experiments like CHIME.
Authors
- Dallas Wulf (ORCID: https://orcid.org/0000-0001-7314-9496)
- Anna Rose Polish
- M. Halpern (ORCID: https://orcid.org/0000-0002-1760-0868)
- Alex Reda (ORCID: https://orcid.org/0000-0001-6967-7253)
- Emily Kuhn
- Tristan Pinsonneault-Marotte (ORCID: https://orcid.org/0000-0002-9516-3245)
- Anna Ordog (ORCID: https://orcid.org/0000-0002-2465-8937)
- Pranav Sanghavi (ORCID: https://orcid.org/0000-0001-5504-229X)
- Maile Harris
- Will Tyndall
- B. R. Saliwanchik
- Laura Newburgh (ORCID: https://orcid.org/0000-0002-7333-5552)
- Seth R. Siegel (ORCID: https://orcid.org/0000-0003-2631-6217)
- J. Richard Shaw (ORCID: https://orcid.org/0000-0002-4543-4588)
- Joshua MacEachern (ORCID: https://orcid.org/0000-0001-8064-6116)
- Kevin Bandura (ORCID: https://orcid.org/0000-0003-3772-2798)
- Audrey Whitmer
- Arnab Chakraborty (ORCID: https://orcid.org/0000-0001-6257-0269)
- Juan Mena-Parra
Institutions
- West Virginia University (US)
- University of British Columbia (CA)
- University of Toronto (CA)
- Brookhaven National Laboratory (US)
- Johns Hopkins University Applied Physics Laboratory (US)
- Yale University (US)
- Canadian Institute for Theoretical Astrophysics (CA)
- Center for Astrophysics Harvard & Smithsonian (US)
- McGill University (CA)
- Okanagan University College (CA)
Publication Details
- Journal
- IEEE Open Journal of Antennas and Propagation
- Published
- 2025-03-24
- DOI
- https://doi.org/10.1109/ojap.2025.3554457
- Citations
- 2
- Primary Topic
- Atmospheric and Environmental Gas Dynamics
- Type
- article
- Field-Weighted Citation Impact
- 2.21
Funders
- National Science Foundation
- Canadian Institute for Advanced Research
- McGill University
- Western Canada Research Grid
- Government of Canada
- Canada Research Chairs
- Industry Canada
- University of Toronto
- Alliance de recherche numérique du Canada
- Institut Périmètre de physique théorique
- Smithsonian Astrophysical Observatory
- Natural Sciences and Engineering Research Council of Canada
- National Research Council Canada
- Fonds de recherche du Québec – Nature et technologies