Scientists are experimenting with a solution to replace the Global Positioning System (GPS), using mobile signals as an emergency backup in case the aircraft’s GPS signal is jammed or interrupted.
The project is being carried out by researchers at Sandia National Laboratories and Ohio State University (USA), aiming to create a secure network for airborne navigation systems.
According to LiveScience on November 26, the research team is using airborne receivers to detect radio waves from communication satellites and mobile towers related to the aircraft. They then use this information to provide navigation data for pilots.
The new system can capture signals from mobile towers at an altitude of 24,300m – (Photo: Sandia National Laboratories).
The research team has attached antenna systems to weather balloons and positioned them in the stratosphere (at altitudes of 6-50 km above the ground) between satellites and mobile towers to detect their individual signals.
Theoretically, this antenna system could function as an emergency beacon if pilots lose GPS signal.
Although GPS is highly accurate, it is not without its issues. GPS signals can be deliberately jammed in and around conflict zones. Hackers can also “spoof” GPS signals to send false information about location or flight direction to pilots.
Additionally, the GPS system can malfunction or stop entirely. People could be in danger if a commercial aircraft loses its GPS signal. Therefore, the team believes that a backup system is essential.
Currently, the research team still has to manually determine which satellites are sending which signals based on available reference data. In the future, they plan to develop an algorithm that allows the antenna systems to automatically identify satellites and use satellite and mobile tower data to determine a person’s location and speed in real-time.
Previous tests of this technology have only reached altitudes of 1,500 – 2,000m. However, the new project has elevated the antenna system to 24,300m. If the system can reliably transmit navigation data from this altitude, it could provide practical benefits for air travel.
While the system hovers at an altitude of 24,300m to receive better signals from both overhead communication satellites and mobile towers on the ground, it is not a perfect method. Satellites focus radio waves down to the Earth for optimal signals on the ground, so strong signals may not always be received at the altitude of the weather balloon.
Therefore, the research team needs to improve detection capabilities and speeds to account for potential errors in the future.
