Munich Airport, an A380 is approaching, 100 meters above the ground the giant bird suddenly aborts the landing and gains altitude again with its turbines spinning. What has happened? In the tower, air traffic controllers detected GNSS interference, i.e. a disruption of the navigation signal. The aircraft was lucky because the interference signal was detected in real time by GIDAS®, a device developed by OHB Digital Solutions GmbH in Graz. The information reached the pilots in the cockpit just in time. GIDAS monitors the GNSS frequency bands and detects any intended or unintended interference. Andreas Lesch, managing director of OHB Digital Solutions GmbH, tells us in an interview how this works and why the scenario described above is still a dream.
Interference – what does this mean and why is it dangerous?
Andreas Lesch: GNSS interference makes proper reception of positioning and time information difficult or impossible. The jammer superimposes all or part of the original signals, thus making them unusable for the receiver. The signals generated by the global navigation satellite system GNSS are susceptible to interference because a navigation signal is relatively weak on the ground – roughly comparable to the power of a 60-watt light bulb. These weak signals can be disrupted by stronger local radio signals or even by fake navigation signals so called “spoofing”. Interference can thus cause considerable economic loss as well as damage to aviation assets. In recent years, GNSS applications have increasingly become the target of interference attacks. One example is the shutdown of navigation equipment at Newark Airport, while US drones have also been forced to land as a result of interference attacks.
So GIDAS provides a shield against criminal intent?
Yes, among other things. Interference may be intentional or unintentional. The unintentional signals are caused by simple (illegal) devices, i.e. small jammers, which private individuals can buy on the Internet for a few hundred euros. They are sold as “privacy protection” devices, but usually have a much higher range than specified and may thus unintentionally cause interference. One example is truck drivers who use jammers to manipulate the systems for monitoring their rest periods. If the driver then approaches an airport with the device accidentally switched on, this may cause considerable interference in the systems. So, these jammers are a major headache. We assume that about three to four sources of interference can be measured along a motorway in Europe. Of course, interference may also be intentional, something which would be tantamount to sabotage. Thus, North Korea has launched GNSS attacks against South Korea or against US drones. Consequently, our device has many interesting uses.
Pretty impressive! What other possible applications are conceivable?
Because GIDAS can detect potential interference in real time, it can also be used in the field of autonomous driving. By integrating GIDAS in the infrastructure, vehicles can receive real-time notification, warning of interference to their navigation systems. The vehicle would then automatically reduce speed and switch to manual operation. But that’s still only a dream.
Sounds great. Can you go into more detail about how GIDAS works?
GIDAS monitors the navigation signals on all frequency bands (depending on the configuration selected) and reliably detects and classifies intentional and unintentional sources of interference. The system is made up of one or more monitoring stations as well as a monitoring center. The monitoring station processes the signals received via antenna with a high-frequency front-end, a high-performance data processing unit and a sophisticated software solution. The monitoring center processes the data received from the monitoring stations, provides the user interface and handles alarm management. All components are designed for installation in 19-inch racks.
Why was OHB Digital Solutions specifically selected for the project?
At OHB Digital Solutions, we have been working with GNSS-based applications for almost 20 years. So, in a nutshell, we are the navigation experts. We were also able to win over ESA with this expertise. GIDAS is a joint project conducted in conjunction with the Joanneum University of Applied Sciences in Graz and was funded by ESA’s Navigation Innovation and Support Program (NAVISP). It ran for a period of around 24 months.
Where do things go from here for GIDAS?
Our sales people are currently working on GIDAS and have already had some promising discussions with potential customers, with more planned for the future. GNSS-based applications have already reached large parts of our everyday life. GIDAS plays a crucial role in ensuring the secure operation of all critical private or public infrastructures.
GIDAS was carried out under a program of and funded by the European Space Agency. The view expressed herein can in no way be taken to reflect the official opinion of the European Space Agency.