GNSS Interference Detection and Localisation

GPS has become ubiquitous in daily life, to an extent that the position, and often more importantly, the time delivered by GPS has become embedded in an increasing number of critical systems. However, given their low received power levels, GPS signals are very susceptible to Radio Frequency Interference (RFI) from either intentional or unintentional sources. In addition to RFI, Spoofing attacks, where fake GPS signals are broadcast to trick the operation of a GNSS receiver, present a serious threat to GNSS reliability and security. This vulnerability is aggravated as satellite navigation becomes more central to the operation of airports, ports railways, and communications systems.

During 2015 a research associate was identified and appointed to work on the follow on Australian Research Council (ARC) sponsored Linkage project partnering with ACSER, the University of Adelaide and GPSat
Systems. This project aims to further extend the capability of GEMS, which was developed as part of the earlier ARC Linkage project with the same partners, to pinpoint attempts to jam or fake GPS signals (spoofers), before either has serious consequences.

Research work to date concentrated on formulating the 3D Angle of Arrival (AOA) based geo-localization of interference sources, and deriving the dilution of precision and Cramer Rao Lower Bound (CRLB) expressions which characterises the accuracy of the proposed approach. Furthermore, an estimator whose performance approaches the CRLB is also developed. Another strand of work is concentrating on the joint AOA and Time Difference of Arrival (TDOA) based geo-localisation. 

2015 also saw the Capability and Technology Demonstrator (CTD) project successfully completing the design review process and manufacture of the multichannel processing platform with extensive tests planned
for 2016.