Measured and computed results of air-to-ground communication performance of 2 aircraft at VHF/UHF frequencies

摘要

The Method of Moments is often used to simulate the radiation patterns of aircraft antennas. The assessment of antenna performance in terms of radiation pattern information alone is difficult, because the overall effect of the pattern on communications performance during typical flight profiles is unclear. We present a numerical methodology to combine the three-dimensional radiation patterns with standard propagation models and evaluate the resulting communications over a realistic flight profile. Numerical grid models radiation patterns are first validated against scale model measured radiation patterns, and thereafter predicted received signal strength iscompared to measured signals during a flight trial. The mean difference in predicted and measured signal strength is 2.8 dB for the transport aircraft trial and 3.46 dB for the trainer aircraft trial using flight profiles with distances ranging between 0 to 70 nautical miles (nmi) and altitudes ranging from 300 ft to 10000 ft. The method allows antenna placement studies to be conducted with more useful results.