GNSS Airport Interference Monitoring System including Localization Capabilities (GAIMS 2)
The goal of the GAIMS 2 project is on the one hand the detection and localization of interfering signals, with respect
to GNSS signals, based on a software defined radio architecture, and on the other hand the assessment and raising of
the awareness of the vulnerability of GNSS.
In the last decade, Global Navigation Satellite Systems (GNSS) have gained an important position within our daily life,
often hidden from plain sight. The fact that GNSS is not only used for positioning but also for timing, synchronisation
of GSM networks, electricity management or bank transfers is not commonly known. Furthermore, a combination of GNSS and
Satellite Based Augmentation Systems (SBAS), like EGNOS, are already used for GNSS-based approach procedures at various
European airports, e.g. in Austria, Graz and Linz. These approaches will be increased in the future in Austria and all
over the world.
While a technology gets more important to our society, the interest of malicious subjects also increases, in harming this
technology. Recent examples are the airport Newark, where the ground based augmentation system (GBAS) used for precise
approaches had to shut down because of a jamming device passing by on the highway surrounding the airport. Furthermore,
at Kaohsiung airport in Taiwan, 117 interfering events per day have been detected during a study. The threat is real.
The "GNSS airport interference monitoring system 2" (GAIMS 2) project relies on the results and algorithms
developed during the GAIMS project. While GAIMS focused on the detection and classification of interfering sources from
an algorithmic point of view, the GAIMS 2 project puts its main focus on the localization of these sources and addresses
the problem of the user awareness. To accomplish these goals, the algorithms developed during GAIMS will be reviewed,
and enhanced if necessary. Furthermore, a difference in received signal strength (DRSS) technique will be used for the
localization of the interfering source. Therefore, at least three interference monitoring modules will be necessary. A
demonstrator hardware will be developed and tested, including a digital signal processor (DSP), which will be able to
process the received data and include the algorithms for interference detection and classification in a software defined
radio (SDR) receiver architecture. This SDR architecture leads to increased flexibility and adaptation of the solutions.
By utilizing a centralised data centre, which gathers information from the interference monitoring modules, it will be
possible to localise the interference source, enabling the prosecution of operators of jamming devices. This is an
important step, since the operation of jamming devices in Austria is illegal.
In parallel to the technological development, the awareness situation regarding unintentional and intentional
interferences and thus the vulnerability of GNSS/SBAS will be analyzed. Currently, most of the users do not recognise
and consider the potential threats adequately, thus leading to potentially huge impacts in our society. The role of the
authorities is currently unclear and no countermeasures exist so far. During the GAIMS 2 project, the awareness will be
raised and a powerful tool provided to the competent authorities which significantly improves the safety and reliability
of GNSS solutions.
TeleConsult Austria GmbH (Lead)
Brimatech Services GmbH
Austrian Research Promotion Agency (FFG)
Successfully completed in 2015