The persistent growth in demand for broadband communication services has lead to the widespread deployment of high-frequency Ka-Band satellite communication systems. This phenomenon however, presents a scenario whereby aircraft in mid-flight are evermore subjected to a diversity of external high frequency signals. The latter can potentially generate Electromagnetic Interference (EMI) with the communications and control avionic systems onboard the aircraft. These drastic effects are becoming increasingly noteworthy, and the aircraft industry is progressively seeking more thorough electromagnetic compatibility assessments prior to aircraft manufacture. To this end, this paper proposes a novel study that computationally models the electromagnetic effects incident on aircraft fuselage from external high frequency sources. An accurate ray-tracing framework was employed for the assessment of the power incident from a terrestrially based Ka-band antenna onto a small sized aircraft whilst flying. Subsequent to the determination of an illumination cone technique, to increase simulation efficiency and accuracy, a customized 3D ray-tracing technique based on Geometric Optics (GO) was used to simulate the propagation characteristics. This asymptotic area-oriented methodology was able to reliably assess the EM field incident on the entire fuselage structure. In addition, the peculiar characteristics of EM waves at the 30 GHz frequency range demanded the inclusion of atmospheric fade phenomena that imposed significant contributions to the attenuation of the EM field. Thus, the performed simulation accounted for signal losses due to rain, fog, cloud, gaseous and also tropospheric scintillation. A large number of rays impeding via an array of diverse propagation paths and techniques were comprehensively considered and the 3D vectorial summation of the resultant EMI field incident on each location was conclusively executed. The paper illustrates the developed theoretical model by presenting computed results for an Evektor EV-55 business aircraft under the typical atmospheric conditions of Geneve, Switzerland for an availability rate of 99percent. This was done because of the extensive atmospheric data available for this location that could be compared with the results obtained from the model. Moreover, the versatility of the developed framework lends itself perfectly to the EMI verification of aircraft models, whereby manufacturers can avoid expensive measurement campaigns at the design stage.
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