Detection, countermeasures and demonstration of GNSS spoofing (DECODE)
Due to the immense increased usage of GNSS-based applications, these applications are also increasingly
jeopardised by sources of intentional interference (i.e. jamming, spoofing). The goal of the DECODE project
is to implement and test state-of-the-art algorithms in a software-defined radio framework as well as to develop
new enhanced algorithms for detection and mitigation of GNSS spoofing attacks. An important part of the project
will be the tests of the impact that spoofers have on a GNSS receiver. The final result will be algorithms and
strategies for GNSS spoofer mitigation.
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 (European GNSS
Overlay Service), are already used for different GNSS applications.
While a technology gets more important to our society, the interest of malicious subjects in harming this
technology also increases. Spoofing attacks, where real GNSS signals are imitated in order to specifically
manipulate the computed position and time of the GNSS receiver, are especially dangerous in this case.
Researchers from the University of Texas in Austin have quite impressively demonstrated the threat of spoofing.
For demonstration purposes they manipulated the position solution of a UAVs GNSS receiver in a way that it landed
although it was programmed to stay at the same place in the air. They also distracted a yacht a few miles away
from its original course, without being noticed by the crew.
The "Detection, Countermeasures and Demonstration of GNSS Spoofing" (DECODE) project has the goal to
develop algorithms for detection and mitigation of spoofing attacks. Therefore current state-of-the-art algorithms
will be implemented in a software-defined GNSS receiver as a first step. The reliability of these algorithms will
be tested and the detailed impacts of spoofing on a GNSS receiver will be analysed using simulations. The
implementation of the algorithms will be conducted in the framework of a software-defined radio GNSS receiver,
which has the necessary flexibility to easily integrate different algorithms. After the first tests, promising
algorithms will be further evolved and new algorithms for detection will be developed based on the acquired
knowledge on spoofers. Detection of spoofers is the first necessary step to eliminate the negative impacts of these
interferers and finally increase the reliability of GNSS applications. To keep up normal operation also in case of
a directed spoofing attack requires advanced algorithms, which can exactly distinguish between real and spoofed
GNSS signals. At the end of this project, the developed algorithms will be investigated and evaluated, which is a
first step from the pure detection to the mitigation of GNSS interference attacks. Further result of the project
will be the design and recommendations for a future system reliably detecting GNSS spoofers.
The DECODE project will increase the Austrian research and development activities and the know-how in the field of
spoofing detection and mitigation, as well as increase the knowledge of the detailed impact of a directed spoofing
attack on all parts of a GNSS receiver. In parallel the project will raise the awareness regarding GNSS threats.
TeleConsult Austria GmbH (project lead)
FH Joanneum Graz (Institute Electronic Engineering)
Austrian Research Promotion Agency (FFG) – ASAP 12