[ Overview |
lucernhammer MT |
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Orion |
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Emerald ]
[ Benchmark Data |
FAQ |
Ordering Information ]
[ Overview |
lucernhammer MT |
Serenity |
Galaxy |
Orion |
Lyra |
Emerald ]
[ Benchmark Data |
FAQ |
Ordering Information ]
UT Austin Camera Box Benchmarks
On this page are presented simulated RCS for the "camera box" targets from the Austin Benchmark Suites for Computational Electromagnetics, a publicly available benchmark suite for RCS simulations. The suite is available on github via the following link:
http://github.com/UTAustinCEMGroup/AustinCEMBenchmarks.
According to the benchmark documentation, "the camera box is designed as a host structure to enable reproducible RCS measurements of ducts".
The construction and measurement of these camera boxes was also discussed in the following paper:
A. E. Yilmaz, E. Smith, S. Cox, B. MacKie-Mason, C. C. Courtney, and G. Burchuk, "Camera boxes: a set of complex scattering problems to test EM simulations and measurements," Proc. IEEE Antennas Propag. Soc. Int. Symp., July 2022.
There are four objects in this benchmark: The first two comprise a tetrahedral "camera box" which is completely closed (no duct), and a similar box with a large, curved duct (cobra duct) leading inside from the front face of the box. The next two comprise a larger version of the camera box. The first has a cylindrical duct, and the second adds to the first a straight-bladed fan to the rear wall of the cylindrical cavity.
Closed Duct
The dimensions and models for the closed camera box are illustrated below. This comprised a simple bounding curve and extrusion in Rhino 3D. The benchmark problem size in this case corresponds to L = 40 cm.
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| Camera Box (Closed Duct) Dimensions From Benchmark | Camera Box (Closed Duct) Rhinoceros 3D Model |
Cobra Duct
The dimensions and model for the camera box with the "cobra duct" are illustrated below. In the benchmark, an IGES (.igs) file comprising a curved surface model of the cobra duct was provided. This model was imported into Rhinoceros 3D and then scaled and rotated, however no other modifications were made. We note that an STL (.stl) mesh of the cobra duct was also provided, however this mesh was of poor quality and was not used for the simulation. Instead, the Rhinoceros 3D was exported and meshed ourselves using Altair Hypermesh.
The benchmark problem size in this case corresponds to L = 40 cm.
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| Camera Box (Cobra Duct) Dimensions (From Benchmark) | Cobra Duct Interior Dimensions (From Benchmark) |
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| Camera Box (Cobra Duct) Rhinoceros 3D Curved Surface Model (Imported Benchmark IGES file) |
Cylindrical Duct
The dimensions and model for the camera box with the "cylindrical duct" are illustrated below. The original camera box host structure used for the "closed duct" and "cobra duct" problem was modified by scaling by 3 in the y dimension and 2 in the z dimension. In the benchmark, an IGES (.igs) file comprising a curved surface model of the cylindrical duct was provided. This model was imported into Rhinoceros 3D and then scaled and rotated, however no other modifications were made. We note that an STL (.stl) mesh of the cylindrical duct was also provided, however as with the cobra duct, the mesh was of poor quality and was not used or the simulation. Instead, the Rhinoceros 3D was exported and meshed ourselves using Altair Hypermesh.
The benchmark problem size in this case corresponds to L = 40 cm.
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Camera Box (Cylindrical Duct) Dimensions From Benchmark |
Camera Box (Cylindrical Duct) Rhinoceros 3D Model (Imported Benchmark IGES file) |
Straight-Blade Fan-Loaded Duct
The dimensions and model for the camera box with the "straight-blade fan-loaded duct" are illustrated below. This target utilizes the cylindrical duct configuration, with the addition of a fan blade assembly attached to the back wall of the duct. In the benchmark, an IGES (.igs) file comprising a curved surface model of the straight-blade fan-loaded duct duct was provided. This model was imported into Rhinoceros 3D and then scaled and rotated, however no other modifications were made. High resolution meshes of varying densities were also provided, of which the mesh named "Straight-Blade_Fan-Loaded_Camerabox_model_meshBC" was selected. This model comprises 385176 nodes and 770348 facets, and is of sufficient density to yield at least 10 unknowns per wavelength at the highest working frequency of 10.24 GHz.
The benchmark problem size in this case corresponds to L = 40 cm.
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Camera Box (Straight Blade Fan Duct) Dimensions From Benchmark |
Camera Box (Straight Blade Fan Duct) Rhinoceros 3D Model (Imported Benchmark IGES file) |
Rhinoceros 3D models are provided below for each object, however these may contain just the bounding curve, or a portion of the 3d surface, etc. If you want to construct a mesh from these models, additional work may be needed, such as revolution around an axis, as well as exporting into a meshing tool of choice. All IGES models converted from the benchmark have been rotated and scaled to units of centimeters.
All calculations below were performed using our code Serenity on a Dell Precision T7900 workstation running Ubuntu Linux, with dual twelve-core Intel Xeon CPUs (E5-2690 v3) at 2.6 GHz with 256 GB of RAM, and dual NVIDIA GTX 1080Ti GPUs, each with 12GB of onboard RAM. Serenity utilizes both GPUs.
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| Closed Duct Camera Box VV RCS, 2.56 GHz | Closed Duct Camera Box HH RCS, 2.56 GHz |
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| Closed Duct Camera Box VV RCS, 5.12 GHz | Closed Duct Camera Box HH RCS, 5.12 GHz |
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| Closed Duct Camera Box VV RCS, 7.0 GHz | Closed Duct Camera Box HH RCS, 7.0 GHz |
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| Closed Duct Camera Box VV RCS, 10.24 GHz | Closed Duct Camera Box HH RCS, 10.24 GHz |
Compared here is the RCS of the UT Austin Closed Duct Camera Box at 2.56, 5.12, 7.0 and 10.24 GHz. We note in the 10.24 GHz data the fairly large discrepancy in the side specular at 90 degrees incident angle. It was stated in the benchmark that "the instrumentation radar used in the measurements were saturated by the high return at 90 degrees for the 10.24 GHz measurement. Thus, the measured RCS values near that look angle are inaccurate."
2.56 GHz Data:
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| Cobra Duct Camera Box VV RCS, 2.56 GHz | Cobra Duct Camera Box HH RCS, 2.56 GHz |
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| Cobra Duct Camera Box VV RCS, 5.12 GHz | Cobra Duct Camera Box HH RCS, 5.12 GHz |
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| Cobra Duct Camera Box VV RCS, 7.0 GHz | Cobra Duct Camera Box HH RCS, 7.0 GHz |
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| Cobra Duct Camera Box VV RCS, 10.24 GHz | Cobra Duct Camera Box HH RCS, 10.24 GHz |
Compared here is the RCS of the UT Austin Cobra Duct Camera Box at 2.56, 5.12, 7.0 and 10.24 GHz. Again we note in the 10.24 GHz data the fairly large discrepancy in the side specular at 90 degrees incident angle.
2.56 GHz Data:
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| Cylindrical Duct Camera Box VV RCS, 2.56 GHz | Cylindrical Duct Camera Box HH RCS, 2.56 GHz |
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| Cylindrical Duct Camera Box VV RCS, 5.12 GHz | Cylindrical Duct Camera Box HH RCS, 5.12 GHz |
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| Cylindrical Duct Camera Box VV RCS, 7.0 GHz | Cylindrical Duct Camera Box HH RCS, 7.0 GHz |
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| Cylindrical Duct Camera Box VV RCS, 10.24 GHz | Cylindrical Duct Camera Box HH RCS, 10.24 GHz |
Compared here is the RCS of the UT Austin Cylindrical Duct Camera Box at 2.56, 5.12, 7.0 and 10.24 GHz. The comparisons are very good.
2.56 GHz Data:
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| Straight Blade Fan Duct Camera Box VV RCS, 2.56 GHz | Straight Blade Fan Duct Camera Box HH RCS, 2.56 GHz |
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| Straight Blade Fan Duct Camera Box VV RCS, 5.12 GHz | Straight Blade Fan Duct Camera Box HH RCS, 5.12 GHz |
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| Straight Blade Fan Duct Camera Box VV RCS, 7.0 GHz | Straight Blade Fan Duct Camera Box HH RCS, 7.0 GHz |
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| Straight Blade Fan Duct Camera Box VV RCS, 10.24 GHz | Straight Blade Fan Duct Camera Box HH RCS, 10.24 GHz |
Compared here is the RCS of the UT Austin Straight Blade Fan Duct Camera Box at 2.56, 5.12, 7.0 and 10.24 GHz. The comparisons are very good. There is a small disagreement between the measured and simulated VV-polarized RCS data at 2.56 GHz around roughtly 20 degrees. A similar disagreement was also noted in the benchmark results.
2.56 GHz Data: