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Numerous 3D modeling tools are being used
in engineering. Despite the obstacles of proprietary file formats and
limited support for open formats, the interoperability of different
modeling tools becomes increasingly important due to overall
optimization of design and production processes. WIPL-D Pro CAD
introduces wide support for transferring various models created in
third-party tools into WIPL-D Pro 3D EM Solver.
The Airbus A320 model, shown in Fig. 1 was imported from an IGES file.
The airplane length is 37.6 m, wing span is 34.1 m. The models contains
details such as windows and jet engine parts. No model repair was needed
after import. Using an adaptive meshing algorithm, an all-quad mesh was
created (Fig. 2) that adequately represented all the details and yet
created larger quads on the fuselage and wings to use the speed of
higher order MoM to full extent.
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Fig 1. Imported model of Airbus
A320 |

Fig 2. Mesh of Airbus A320 – Full
model, no defeaturing |
Using the cropping and defeaturing
techniques in WIPL-D Pro CAD, the model was split in half and simplified
by removing all windows (Fig. 3). A quarter wavelength monopole was then
placed on the fuselage and the gain of the system was calculated at 833
MHz, with the airplane being 104 λ long at this frequency.
Rigorous higher order MoM in combination with adaptive expansion order
reduction and the out-of-core solver results in:
|
Frequency |
No. of unknowns |
Disk space used |
Simulation time |
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833 MHz |
66,279 |
32.8 GB |
6.1 hours |
The resulting radiation pattern in the symmetry plane is shown in Fig.
4.
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Fig 3. Mesh of Airbus A320 – Half
model, windows removed |

Fig 4. Gain in the symmetry plane
at 833 MHz of a monopole placed on top of the fuselage, close to
the nose |
Placement of a small antenna on three
different positions on the aircraft was investigated next in order to
establish the influence of the wings and the tail on the radiation
pattern. A half-wavelength dipole was placed above the airplane fuselage
at midpoint between the wings and the nose, at wings, and at midpoint
between the wings and the tail (Fig. 5). The simulation frequency was
1.53 GHz which meant the airplane was about 190 λ long.
Rigorous higher order MoM in combination with adaptive expansion order
reduction and the out-of-core solver results in:
|
Frequency |
No. of unknowns |
Disk space used |
Simulation time |
|
1.53 GHz |
105,400 |
88.2 GB |
31.5 hours |
The simulations were done on a desktop computer with a Core 2 Quad CPU
running at 2.83 GHz clock rate.
The radiation patterns in the symmetry
plane for three different positions of the dipole are shown in Fig. 6.
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Fig 5. Three positions for
placing a dipole |

Fig 6. Radiation patterns for
three positions of the dipole |
The influence of the tail is clearly
visible in case when the dipole is placed at the back (the encircled
disturbances in Fig. 6).
A comparison of the three radiation patterns with a radiation pattern of
a dipole above infinite PEC plane is given in Fig. 7. This can give us a
hint as to how large of a difference is between the airplane fuselage
and a infinite flat PEC plate at the frequency of interest. The diagram
shows that the position of the placed antenna does not make a
significant influence to the overall radiation pattern and that
hemispherical coverage of the space above the airplane is possible even
from a position near the tail (Fig. 8 gives the radiation pattern in
dB).
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Fig 7. Comparison of radiation
pattern for three dipole positions with the radiation pattern of
a dipole above infinite PEC plane |

Fig 8. Comparison of radiation
pattern for three dipole positions with the radiation pattern of
a dipole above infinite PEC plane – in dB. |
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