Real-time Radio Frequency Interference Detection and Mitigation with the Front-End GNSS Interference eXcisor (FENIX)

The number of applications based on Global Navigation Satellite Systems (GNSS) has been increasing in the last years. With its proliferation, Radio-Frequency Interference (RFI) has become one of the most concerning topics on GNSS-based devices for navigation, positioning and timing, but also for Earth Observation purposes such as GNSS-Reflectometry (GNSS-R) and GNSS-Radio Occultations (GNSS-RO) due to the corruption of the received signal and the corresponding geophysical measurements. The Front-End GNSS Interference eXcisor (FENIX) mitigates the problem of RFI by providing a plug-and-play solution which, placed between the antenna and the receiver, excises virtually any kind of interference signal, as its mitigation algorithm is agnostic on the particular type of RFI. The new version of FENIX is also capable of operating with large signal bandwidths ($\sim$50 MHz) and dual-band applications (e.g. L1 + L2 or L1/E1 + L5/E5). This paper shows the performance of the system for commercial GNSS receivers and GNSS-R applications. The use of FENIX in Microwave Radiometers is also possible, but it is out of the scope of this paper.