Special Issue — Digital Signal Processing in Radio Astronomy; Guest Editors: Danny C. Price, Jonathon Kocz, Matthew Bailes and Lincoln J. GreenhillNo Access

Towards Real-Time Impulsive RFI Mitigation for Radio Telescopes

Kaushal D. Buch

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

E-mail Address: kdbuch@gmrt.ncra.tifr.res.in

Corresponding author.

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Shruti Bhatporia

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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Yashwant Gupta

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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Swapnil Nalawade

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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Aditya Chowdhury

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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Kishor Naik

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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Kshitij Aggarwal

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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, and

B. Ajithkumar

Giant Metrewave Radio Telescope, National Centre for Radio Astrophysics, TIFR, Pune, Maharashtra 411007, India

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https://doi.org/10.1142/S225117171641018XCited by:11 (Source: Crossref)

Abstract

Radio Frequency Interference (RFI) is a growing concern for contemporary radio telescopes. This paper describes techniques for real-time threshold-based detection and filtering of broadband and narrowband RFI for the correlator and beamformer chains of a telescope back-end, with specific applications to the upgraded Giant Meterwave Radio Telescope (uGMRT). The Median Absolute Deviation (MAD) estimator is used for robust estimation of dispersion of the received signal in temporal and spectral domains. Results from the tests carried out for the GMRT wide-band backend (GWB) using this technique show 10 dB improvement in the signal-to-noise ratio. MAD-based estimation and filtering was also found to be useful for filtering beamformer data. The RFI filtering technique demonstrated in this paper will find applications in other radio telescopes as well as receivers for digital communication and passive radiometry.

Keywords:

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