Coordinated Resource Allocation Scheme for 5G Direct Air-to-Ground Communication

Abstract:
There is an increasing demand for in-flight broadband connectivity. Some airlines are already deployed satellite-based solutions, which have low data rate and high latency. In order to tackle these problems, direct air-to-ground communication (DA2GC), where a direct link between a ground station and an airplane is established, is a promising solution. The resource utilization in DA2GC systems can be enhanced with the introduction of multi-user beamforming techniques, where each airplane has its dedicated beam and exploits a larger portion of the spectrum available to DA2GC. Even with multiuser beamforming technique, some airplanes may experience low data rates due to interference caused by beams aimed at airplanes in the mutual vicinity. The probability that two or more beams will interfere is higher with longer inter-site distance or wider beamwidth, which is often the case for DA2GC systems. To address significant research problem, we propose a coordinated resource allocation scheme with beam selection and spectrum allocation. The proposed beam selection scheme coordinates the neighboring base stations such that the number of airplanes sharing the same beam is minimized. In addition, the proposed coordinated spectrum allocation scheme maximizes the minimum amount of spectrum dedicated for each airplane. According to our results, the proposed coordinated beam selection with efficient spectrum allocation improves average capacity available per airplane by 60% in comparison with the uncoordinated scheme.