

Various types of signals are used to jam GNSS signals, including pulse, continuous, wideband, or narrowband interference. The structure, type, and power of these jamming signals depend on the jammer employed. Simple generators can produce interference on a single frequency (e.g., L1) of a single satellite constellation (e.g., Global Positioning System). More complex devices can interfere with signals from several constellations (e.g., GPS, Galileo, GLONASS, BeiDou) across multiple frequencies (e.g., L1, L2, L5, E1, E5). Another factor is the structure of the jamming signal itself and how it changes during the jamming event (e.g., a simple chirp signal, a pulse signal, or “smart jamming”).
Unlike natural signal changes caused by tropospheric delays, multipath propagation, scintillations, solar storms, and cosmic radiation, jamming is a deliberate form of signal interference. It blocks GNSS signals by generating signals of usually higher power within their frequency band. This causes the end-user’s receiver to process the interference signal instead of the useful GNSS signal. As a harmful activity that hinders or prevents the use of GNSS and GNSS-based services, jamming is illegal and prosecuted by law in Poland and other countries. From a user’s perspective, jamming causes total or partial unavailability of GNSS services, preventing precise navigation, creating problems with the synchronization of power and telecommunications networks, and disrupting emergency services and crisis management coordination systems.
Press reports indicate a significant increase in jamming incidents in north-eastern Poland (especially in the Gdańsk Bay area), Lithuania, Latvia, Estonia, Finland, Sweden, Ukraine, and countries in the Mediterranean and Middle East regions. The impact of jamming can have serious consequences for the economy, industry, social life, and the daily functioning of individuals.


One effective method of protection against jamming is the use of specialized anti-jamming antennas. Jamming blocking devices are also becoming increasingly popular. Systemics – PAB, in collaboration with Safran, offers solutions that mitigate or eliminate jamming, which is crucial for end-users and their applications. The following solutions are noteworthy:
8230AJ GPS/GNSS Anti-Jam Antenna
This antenna eliminates interference with GNSS signals propagated at GPS L1, GLONASS L1, BeiDou B1, Galileo E1, and QZSS L1 frequencies.
Detailed information about the antenna can be found on the Safran website.
GPSdome Anti-Jamming Device
This device connects between the antenna and the GNSS receiver, providing protection and continuity of autonomous GPS navigation and operation even under GPS L1 (C/A code) signal jamming conditions.
Detailed information about the device can be found on the Safran website.
BroadShield Software
This software contains a number of patented algorithms designed to detect jamming and spoofing, enabling immediate reporting of interference to a GNSS-based system/application.
Detailed information about the software can be found on the Safran website
