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    Modelling of effects of nose radomes on radar antenna performance
    (IEEE, 2016) Lansink Rotgerink, J.H.G.J. ; Ven, H. van der ; Voigt, T. ; Jehamy, E. ; Schick, M. ; Schippers, H.
    This paper describes two computational models for the assessment of effects of nose radomes on the performance of radar antennas. The first model is an improved Physical Optics approach that takes into account the wall thickness and multiple layers of the radome. The second model follows from the accelerated numerical solution of Electric Field and Magnetic Field Integral equations. The models are applied to predict the radiation patterns of a radar antenna behind a generic nose radome and behind a radome of a fighter aircraft. The applicability of the two models is discussed.
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    Shielded Aircraft Windows to Protect Radio Altimeters in the Presence of Wireless Avionics Intra-Communication
    (IEEE, 2023) Konter, Y.E.J. ; Blaauw, K. ; Lansink Rotgerink, J.H.G.J.
    Wireless Avionics Intra-Communications in the frequency range of 4.2 to 4.4 GHz is an upcoming solution to replace the cabling of part of the data network in aircraft with a wireless alternative. This solution shares its frequency band with the radio altimeter and is therefore subject to limitations on the transmitted power to ensure compatibility with flight critical equipment of the aircraft. This paper presents simulation results on the effectiveness of shielded aircraft windows to protect radio altimeters in the presence of wireless avionics intra-communication. A propagation model is developed to simulate how shielded cabin windows affect the EIRP of WAIC transmitters within the cabin of an aircraft. Simulation with this model show that a reduction in EIRP of roughly 15 dB can be expected when electromagnetic coating is applied to the passenger windows. These results can be used in the design of robust WAIC network solutions that are compatible with legacy aircraft equipment.
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    Multiconductor Transmission Line Modeling of Crosstalk Between Cables in the Presence of Composite Ground Planes
    (IEEE, 2021) Lansink Rotgerink, J.H.G.J. ; Serra, R. ; Leferink, F.
    Modern transportation systems, such as aircraft, are increasingly replacing metal body parts for composite materials, such as carbon-fiber reinforced plastics. Despite the multiple advantages in terms of weight, size, and fuel consumption, this trend is posing a challenge for protection of cables against electromagnetic interference. Early risk assessment and optimization of cable design in modern aircraft require reliable methods that can quickly and accurately estimate crosstalk behavior in the presence of lossy ground planes. This article presents two novel methods to incorporate such lossy ground planes into the crosstalk modeling of cable bundles. The first method considers the ground plane as a discrete collection of cylindrical conductors. In the second method a ground impedance matrix is derived for lossy ground planes with a finite thickness. Results of both methods are compared to full-wave simulations and measurements, yielding excellent results in terms of accuracy and computation times. The discretized ground plane method is also applied to the case of wire pairs that are enclosed by two ground planes, both aluminum and carbon–fiber reinforced plastic, as a first step towards investigation of wiring that is embedded in thermoplastic material. Once more simulations and measurements are in good agreement.
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    Power Line Communications for Avionics Systems: Robustness Against Electromagnetic Compatibility
    (IEEE, 2023) Lansink Rotgerink, J.H.G.J. ; Dominiak, S. ; Dietrich, G. ; Reznícek, Z.
    Electrification of numerous aircraft systems over the course of the past decades has caused a significant increase in weight and complexity of onboard power and data networks, and this trend is expected to continue on the road towards sustainable aviation. Hybrid data networks that combine conventional cabling with wireless technologies and power line communication have the potential to yield data networks with reduced weight. However, in doing so, safety should not be compromised. Therefore, this paper presents the results of a measurement campaign that was carried out to investigate the robustness of Power Line Communications with respect to Electromagnetic Compatibility. The tests include conducted susceptibility, as well as conducted and radiated emissions. Three different wiring configurations were tested, being a single wire and bifilar wire with structure as return, complemented by a wire pair with dedicated return wire. Overall, except for the single wire case, Power Line Communications performed well on all tests, with the bifilar wiring case slightly outperforming the wire pair case. Resonance phenomena observed in conducted emission results are explained by additional simulations.
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    Simulation of radiated emission by shielded power feeders for electric propulsion of aircraft
    (IEEE, 0023) Lansink Rotgerink, J.H.G.J.
    Hybrid electric propulsion as one of the solutions towards sustainable aviation brings on-board a powertrain with high power levels, voltages and currents. In terms of electromagnetic compatibility this will inevitably raise conducted and radiated emission challenges. Power feeders may become a maj or source of electromagnetic radiation. This paper uses combined multiconductor transmission line and Hertzian Dipole methods to predict such radiated emissions of three-phase power feeders that include shielding. Results of simulated radiated emissions of a shielded trefoil cable are compared to full-wave simulations, models from literature, as well as measured results. Finally, the method is combined with simulated currents in a Simulink model of an electric powertrain, to obtain predicted in-situ radiated emissions of a shielded AC power feeder.