Propagation and system dimensions in extremely high frequency broadband aeronautical SatCom systems
The potentialities of using EHF frequencies on a satellite for aeronautical broadband communication provision have been discussed in this chapter. Currently used Ka band frequencies will soon not be able to cope with the increased Internet demands from aircraft passengers. There do not appear to be any major regulatory barriers to adopting Q/V and W bands, except perhaps around airports. It has been shown that the propagation impairments in the troposphere that are preventing for now the use of those bands for satellite user links are not a major issue for aeronautical applications as the magnitude of those impairments is significantly decreasing with altitude. They are almost negligible at cruise level. The various tools available to size the propagation margins have been detailed. An outcome of the analysis is that the margins required to ensure more than 99.9% of availability could be lower than 10 dB for most of the flight configurations at Q/V and W band. In order to get an idea of the improvement of the performances brought by the use of those higher frequency bands, current aeronautical terminals and satellites characteristics' have been extrapolated to EHF. It has been shown that the capacities provided can be enhanced by use of conformal antennas and provide from 4 to 10 times increases over current Ka band systems. These would appear to accommodate the predicted requirements of around 200Mbps per aircraft made for 2020 and beyond. This demonstrates the feasibility of EHF satellite systems to meet future Aero passenger requirements, letting bandwidth for ground-based applications at lower frequency bands.
Propagation and system dimensions in extremely high frequency broadband aeronautical SatCom systems, Page 1 of 2
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