Radio frequency interference detection and mitigation are becoming of paramount importance due to the increasing number of services and applications based on the position obtained by means of Global Navigation Satellite Systems. A way to cope with such threats is the implementation in the receiver of advanced signal processing algorithm able to raise proper warning or improve the receiver performance. In this paper, we propose a method based on the Wavelet Transform able to split the useful signal from the interfering component in a transformed domain. The wavelet packet decomposition and proper statistical thresholds allow the algorithm to show very good performance in case of multiple pulse interference as well as in the case of narrowband interference, two scenarios in which traditional countermeasures might not be effective. 1. Introduction Reliable positioning and navigation are becoming imperative in a growing number of applications that are being developed for public services and safety critical purposes. As a consequence, satellite and radio navigation is evolving in an accelerating pace and it is becoming a pervasive technology in a large number of consumer and professional devices. For such a reason, parallel to the development of techniques able to improve the positioning accuracy, the research is becoming of paramount importance to improve the robustness of the positioning methodologies in order to make sure that the navigation is trustworthy and the risks and threats are properly accounted for. As far as Global Navigation Satellite Systems (GNSS) based techniques, intentional or unintentional interference represents one of the main threats to be considered. GNSS receiver operation can be easily disrupted by interfering signal due to the extreme weakness of the GNSS signals reaching the GNSS user antenna. In fact, the presence of undesired RFI and other channel impairments can result in degraded navigation accuracy or complete loss of receiver tracking [1]. Furthermore, due to the lack of frequency allocations, the majority of the interference issues come from the presence of other communication systems which broadcast strong signals on frequencies within or located near the GNSS frequency bands. As an example, the terrestrial Digital Video Broadcasting (DVB-T) system may represent a real threat for the GNSS receiver operation. In fact, nonlinearity distortion generated in the DVB-T transmitter amplifier may lead to the generation of harmonics in the GPS L1 (and thus Galileo E1) frequency band. In [2] a set of on-field experiments aiming at
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