Researchers at King Abdullah University of Science and Technology (KAUST) developed a new mathematical approach to protect aircraft from interference caused by mobile communication signals, reported the Saudi Press Agency on Wednesday.
The solution was published in the scientific journal IEEE Transactions on Wireless Communications, where the team described the concept of an “ideal exclusion zone” that protects critical aircraft systems while simultaneously enhancing the performance of fifth-generation (5G) networks.
The results are expected to assist aviation and telecommunications regulators in formulating policies for network deployment near air traffic routes.
This marks the first time stochastic geometry - a mathematical method used to model randomly placed network elements - has been applied to predict how 5G signals interact with aircraft radio altimeters.
Data is transmitted as electromagnetic waves across specific frequency bandwidths. The wider the frequency bandwidth, the faster data is shared. 5G operates at the widest frequency bandwidth, allowing the transmission of more data at faster rates. However, some bandwidths become problematic with other systems.
The study’s lead researcher at KAUST, Professor Mohamed-Slim Alouini, explained that 5G operates near the same bandwidth as aircraft radio altimeters, which may cause signal interference. This, he noted, highlights the need to establish exclusion zones to reduce interference levels.
Although 5G networks have already caused numerous flight cancellations worldwide due to interference, Alouini’s team proposed a solution based on establishing exclusion zones where 5G towers operate only at lower frequency bands, relying on previously available spectrum instead of the newer, higher-frequency bands.
Stochastic geometry is used to analyze different shapes of exclusion zones, with triangular areas around runways shown to preserve radio altimeter signals while minimizing the loss of 5G network performance. The team applied this method to predict interference patterns and assess the impact of various exclusion zone designs on safety and performance.
The results indicated that 5G performance drops by 20% with just one tower inside the zone, and by up to 50% with three towers.
The implications of this study extend beyond the Kingdom, as many countries have already imposed restrictions on 5G networks near airports due to concerns over aircraft radio altimeters.
Conducted with support from Saudi Arabia’s Communications, Space & Technology Commission (CST), the study is expected to help shape global policies that enable the coexistence of 5G networks and radio altimeters.
