Aviation Multicarrier Communication System Performance in Several 5 GHz Band Air-Ground Channels - Invited Paper

Aviation traffic is on the rise, in part due to a large increase in the number of unmanned aerial systems (UAS), also known as unmanned aerial vehicles (UAVs). With the rise in vehicle traffic will come increased communication traffic, and for the air-ground communications to/from all these air vehicles, new communication systems are required. In this paper we evaluate via simulations the performance of two new candidate systems over empirical air-ground channel models. These channel models - here for the 5 GHz band - are based on an extensive measurement campaign sponsored by NASA, with ground sites in multiple local environments. The two new multicarrier candidate schemes are 5 MHz bandwidth systems: a cyclic-prefix OFDM scheme similar to the previously proposed L-DACS1 scheme, and a new filterbank multicarrier (FBMC) scheme related to a prior L-band FBMC design of the authors. By taking advantage of the more compact FBMC spectrum, we can improve spectral efficiency via replacement of band-edge guard subcarriers with data-bearing subcarriers. Our design increases throughput by approximately 23%. The (uncoded) bit error ratio performance of the two schemes is evaluated for several modulations over three specific air-ground channels, and performance results are very similar between the two schemes: even in the worst-case channels and with highest modulation order, the FBMC bit error ratio is only marginally larger than that of the CP-OFDM scheme. Hence with nearly identical performance and significantly better throughput, the FBMC design is an attractive candidate for future air-ground communications in these settings.