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arXiv · 2605.08479

Wideband RFI Monitor Requirements, Design, and Commissioning at DRAO

Nicholas Bruce·Charl Baard·Stephen Harrison·Mohammad Islam·Abraham J. Otto·Dustin Lagoy·Robert Messing·Benoit Robert·Timothy Robishaw·Peter F. Driessen
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Abstract

In this paper, we introduce the radio frequency interference monitor deployed at the Dominion Radio Astrophysical Observatory. It provides 2 GHz of instantaneous bandwidth, supporting channel bandwidths as fine as ~100 Hz for 1 s integrations, or integration times as low as ~50 ms for the standard 3.33 kHz channel bandwidth. After operating as a prototype instrument for several years, the monitor was commissioned to improve the calibration method, analog section temperature, and gain stability. It now operates both as a transient detector and as a long-term radio environment characterization tool. We introduce novel applications for the monitor and derive a new method for calculating the effect of gain drift on integrated data.

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Nicholas Bruce, Charl Baard, Stephen Harrison, Mohammad Islam, Abraham J. Otto, Dustin Lagoy, Robert Messing, Benoit Robert, Timothy Robishaw, Peter F. Driessen. 2026-05-08. Wideband RFI Monitor Requirements, Design, and Commissioning at DRAO. https://doi.org/10.1088/1538-3873%2Fae6978

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