Methods of Creating Directional Electromagnetic Interference for Selective Influence on GPS/Glonass: A Review

Directional electromagnetic interference (DEMI) is an advanced method for selectively influencing Global Navigation Satellite Systems (GNSS), such as GPS and GLONASS, by generating controlled disruptions in targeted locations or frequency bands. The ability to precisely control electromagnetic interference is essential for applications in electronic warfare, cybersecurity, and controlled testing of GNSS vulnerabilities, where traditional wide-area jamming techniques may cause unnecessary collateral disruptions. The principle of directional EMI relies on advanced technologies, including beamforming, phased array antennas, and software-defined radio (SDR) systems, to focus interference on specific receivers or geographic areas while minimizing unintended effects. The effectiveness of DEMI is influenced by several key factors, including the power and directionality of the interference source, the receiver’s ability to mitigate signal disruptions, and environmental conditions such as multipath interference and ionospheric disturbances. Experimental studies demonstrate that adaptive interference generation using techniques such as beam- steering, null-steering, and frequency-hopping can enhance the precision of GNSS disruption. These methods allow for controlled denial of positioning services in a localized area without affecting broader satellite operations or civilian applications. The increasing reliance on GNSS for military, commercial, and civilian navigation underscores the importance of studying both interference and countermeasure techniques. Digital signal processing (DSP)-based mitigation strategies, including adaptive notch filtering, pulse blanking, and Karhunen-Loeve transforms, provide methods to reduce susceptibility to directional jamming. However, ethical and legal considerations must be addressed to ensure that DEMI technologies are used responsibly, particularly in environments where GNSS integrity is critical for aviation, maritime operations, and emergency response systems.