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arXiv · 1903.00588

Statistical discrimination of RFI and astronomical transients in 2-bit digitized time domain signals

Gelu M. Nita·Aard Keimpema·Zsolt Paragi
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Abstract

We investigate the performance of the generalized Spectral Kurtosis (SK) estimator in detecting and discriminating natural and artificial very short duration transients in the 2-bit sampling time domain Very-Long-Baseline Interferometry (VLBI) data. We demonstrate that, while both types of transients may be efficiently detected, their natural or artificial nature cannot be distinguished if only a time domain SK analysis is performed. However, these two types of transients become distinguishable from each other in the spectral domain, after a 32-bit FFT operation is performed on the 2-bit time domain voltages. We discuss the implication of these findings on the ability of the Spectral Kurtosis estimator to automatically detect bright astronomical transient signals of interests -- such as pulsar or fast radio bursts (FRB) -- in VLBI data streams that have been severely contaminated by unwanted radio frequency interference.

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Gelu M. Nita, Aard Keimpema, Zsolt Paragi. 2019-03-02. Statistical discrimination of RFI and astronomical transients in 2-bit digitized time domain signals. https://doi.org/10.1142/s2251171719400087

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