GNSS Signal Jamming as Observed From Radio Occultation

• Published in: IEEE journal of selected topics in applied earth observations and remote sensing Vol. 17; pp. 8642 - 8645
• Main Author: Wu, Dong L.
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Amplitude; Amplitudes; Atmospheric measurements; Electronic warfare; Global navigation satellite system; Global navigation satellite system (GNSS); Global Positioning System; Global positioning systems; GPS; Jamming; Long-term changes; Navigation; Navigational satellites; Noise levels; Radio; Radio occultation; radio occultation (RO); Receivers; Satellite observation; Sea measurements; Signal to noise ratio; time series
• ISSN: 1939-1404; 2151-1535
• DOI: 10.1109/JSTARS.2024.3385738

The jamming is found to increase significantly in recent years, and its impact is evident in Global Navigation Satellite System (GNSS) radio occultation (RO) measurements, such as those from COSMIC-2. This article presents an algorithm that applies the RO radiometry to detect and monitor long-term variations of GNSS jamming power from a deeply occulted height (H SL = −140 km). At these heights, the RO signal amplitude is at its noise level because the GNSS transmitter is far behind the Earth shadow. Thus, any enhanced RO amplitudes from these heights are considered as a jamming signal. The algorithm was successfully applied to two conflict zones: Mediterranean Sea and Middle East and Central Africa, where the Global Position System (GPS) jamming was frequently used by state-sponsored electronic warfare. The time series of normalized RO amplitude in these regions show a steady increase of the GPS jamming power since 2017, but a sharp decrease since the start of Russo-Ukrainian War.