An Update on the External Calibrator for Hydrogen Observatories (ECHO)

Yifan Zhao; Daniel C. Jacobs; Titu Samson; Mrudula Gopal Krishna; Michael Horn; Marc-Olivier R. Lalonde; Raven Braithwaite; Logan Skabelund

arXiv · 2407.03462

An Update on the External Calibrator for Hydrogen Observatories (ECHO)

Yifan Zhao·Daniel C. Jacobs·Titu Samson·Mrudula Gopal Krishna·Michael Horn·Marc-Olivier R. Lalonde·Raven Braithwaite·Logan Skabelund

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Abstract

Precision measurements of the beam pattern response are needed to predict the response of a radio telescope. Mapping the beam of a low frequency radio array presents a unique challenge and science cases such as the observation of the 21\,cm line at high redshift have demanding requirements. Drone-based systems offer the unique potential for a measurement which is entirely under experimenter control, but progress has been paced by practical implementation challenges. Previously, a prototype drone system, called the External Calibrator for Hydrogen Observatories (ECHO), demonstrated good performance in making a complete hemispherical beam measurement. This paper reports updates to the system focusing on performance of a new drone platform, minimizing interference from the drone, and a new transmitter.

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BibTeX RIS

Yifan Zhao, Daniel C. Jacobs, Titu Samson, Mrudula Gopal Krishna, Michael Horn, Marc-Olivier R. Lalonde, Raven Braithwaite, Logan Skabelund. 2024-07-03. An Update on the External Calibrator for Hydrogen Observatories (ECHO). https://arxiv.org/abs/2407.03462

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