Global navigation satellite systems (GNSS) and, in particular, the global positioning system (GPS) have become ubiquitous in safety critical infrastructure. Vulnerability of GNSS to radio frequency interference (RFI) from either intentional (jamming) or unintentional sources is an ever growing concern. Hence, GNSS itself has become critical infrastructure which must be protected and its vulnerability to interference alleviated. As the RFI source is unknown a priori, passive localization systems are required; this adds an order of difficulty when compared with transmitter location systems with known and cooperative sources. The need for rapidly localizing the RFI leads to sensor network techniques which consist of spatially distributed sensor nodes (SNs). The localization systems typically use the received signal strength (RSS), source angle of arrival (AOA)/direction of arrival (DOA), time difference of arrival (TDOA) or a combination of AOA(DOA)/TDOA or frequency difference of arrival (FDOA) measurements to estimate the RFI position. This paper provides an overview of existing systems from the literature and a comparison of these different interference geo-localization techniques.
- Global navigation satellite systems (GNNS) vulnerability
- Radio frequency interference