Effects of Interference Mitigation Methods on Scintillation Detection

The use of Global Navigation Satellite Systems (GNSS) signals as signal of opportunity for ionospheric sounding is becoming quite popular. In particular, for scintillation monitoring, it is essential that the affected GNSS signal is not distorted by any other artificial interference. As a matter of fact, the Ionospheric Scintillation Monitoring Receivers (ISMR) used to observe scintillation activities could operate in scenarios where communication systems or even jammers are present. Such sources can provide scintillation-like performance in the signal processing stage, leading to misconceptions about the behavior of actual scintillation phenomena. This paper investigates the estimation of the S4 index, generally used to detect the presence of a scintillation event, under five types of anthropogenic interference, including continuous wave, narrow band, wide band, chirp and pulsed interference. Furthermore, the study also addresses the use of notch filtering and wavelet packet decomposition to mitigate the anthropogenic interference from a scenario in which both scintillation and artificial interference are present, and the S4 is estimated on the mitigated data.