On the Application of Beamforming in LDACS

Currently, aeronautical communications is undergoing a modernization process from analog to digital technology. The L-band Digital Aeronautical Communications System (LDACS) is the upcoming digital data link for air-ground communications and is being standardized within ICAO as well as EUROCAE at the moment. A wireless communication system can be interrupted by intended or unintended jamming signals. Therefore, the robustness of wireless systems is crucial. In this paper, we investigate the use of beamforming in LDACS to improve its performance and robustness. We analyze different antenna array designs and assess their performance to find the most suitable configuration for LDACS. Accordingly, the chosen antenna array design is evaluated for different flight scenarios considering a realistic LDACS link budget. We show that the chosen phased antenna array design improves the signal-to-noise-ratio of the LDACS reverse link by over 10 dB. Hence, using beamforming, the robustness of LDACS can be enhanced and higher data rates can be achieved by applying the built-in LDACS adaptive coding and modulation capabilities.