• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.622-628
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• 1998

The SONAR(SOund NAvigation and Ranging) is the system that detects objects and finds their locations in water by using the echo ranging technique. In this paper, the scattering phenomena for a rigid spherical scatterer will be analyzed using closed form solution, Boundary Element Method and Finite Element Method. Scattering analysis for an elastic spherical scatterer will be analyzed, later. In oder to analyzing the sound wave scattering phenomena for an elastic scatterer in water coupled problem between acoustic and vibration must be considered.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.5
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• pp.323-331
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• 1986

By solving the current distribution, natual frequencies, and the amplitude of natural modes about the perfect conducting scatterer of revolution are presented. Singularity expansion method is applied to slove the time-domain response based on the simplified E-field integral equation by the application of the extended boundary conditin for the perfect conductin scatterer of revolution.

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.32-35
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• 2008

We fabricated surface pattern on a light guide panel (LGP) using $CO_2$ laser to improve the luminescence performance of inner-scatterer LGP, which is made of PMMA sample with exploiting Q-switched $2^{nd}$ harmonic Nd:YAG laser engraving system, and the effect of surface pattern in the brightness distribution of LGP was analysed. To prove the feasibility of proposed method in the enhancement of LGP performance, we designed three different surface patterns on the inner-scatterer LGP. The experimental results has proved the potential in the application of surface pattern to increasing the brightness of inner-scatterer LGP.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.3
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• pp.163-170
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• 2010

Both scatterer method and transfer matrix method are compared to analyze their characteristics, which are wave propagation models due to topographic change based on plane wave approximation. Results from the scatterer method are closer to the results obtained by the more accurate existing models and it is appraised that the scatterer method gives the clearer explanation about physical process involved in the wave transformation. Since both methods have analytical solutions, in the computational point of view they are very fast and easy to be implemented. Both methods give a good prediction for wave scattering by relatively simple bedform.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.5
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• pp.439-451
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• 2008

Based on reflected and transmitted waves by a single step bottom, a new model of scatterer method is constructed which can be used to calculate wave transformation over a multi-step topography. The approximate results are tested by comparison with the more accurate results obtained from EFEM presented by Kirby and Dalrymple(1983). In the case of plane-wave approximation, solutions of the scatterer method and the EFEM are the same. Results obtained by the scatterer method with non-propagating modes are much better, in terms of phase for the calculated reflection and transmission coefficients, than those by plane-wave approximation. As the effect of non-propagating modes decreases, solutions of the scatterer method become closer to those of the EFEM.

• Journal of the Korea Society for Simulation
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• v.30 no.4
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• pp.21-29
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• 2021

Inverse synthetic aperture radar (ISAR) image is a powerful tool to show the major scattering regions (scatterer points) on the target. It is normally used to identify and classify targets. Finding information for the scatter points of ISAR image plays an important role in modeling the features of targets. In this paper, we propose a modeling method to extract some information about the scatterer points by minimizing approximating error. Here, the extracted information include not only the location of scatterer points but also some statistical data about the error of the their location. These extracted data can be used to implement the randomness of the location of the scatterer points. Furthermore, we reconstruct an image from the extracted data for scatterer points obtained by our proposed method. And we show that the reconstructed ISAR image is well approximated to the original ISAR image in order to justify our proposed modeling method.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.13-17
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• 1987

Electromagnetic wave scattering from the two-dimensional scatterer was calculated by the Boundary Element Method (BEM). For the circular cylindrical scatterer, the BEM solutions agreed very well with the analytic solutions. The rectangular dielectric cylinder was also treated in the case of the lossy scatterer and the lossy medium.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.138-141
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• 2007

The permanent scatterer SAR interferometry (PSInSAR) technique has been developed more recently and has been applied to monitor slow but consistent ground subsidence. Since PSInSAR has the advantages in terms of baseline and temporal decorrelation, PSInSAR technique using X-band may also provide useful information about a ground deformation in detail. We developed our codes for a persistent scatterer analysis, and then apply to ERS-1/2 C-band data over Las Vegas in order to validate our new developed algorithm. Based on this test, PS technique using X-band observation such as TerraSAR-X or KOMSAT 5 will be developed.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2001.11a
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• pp.20-24
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• 2001

Two types of radiative coupling in the 2-dimensional aperture to scatterer coupling problems are described with an emphasis on the main difference between the two types. In particular, detailed comparison is made from the viewpoint of the Quality factor between two types.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.43-48
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• 2018

Offset parabolic antenna have been widely used for satellite communication system. To locate feedhorn on antenna system, it requires arbitrary structure which forces to fix on system. However, arbitrary scatterer increases sidelobe level of elevation axis. To solve this problem, we need to predict which angle level is increased by arbitrary scatterer simply. Because conventional simulation method takes a long time to simulate parabolic antenna system and needs exclusive software. In this paper we can calculate sidelobe angle simply by using raytracing method, check coincidence between calculated and simulated result and show how arbitrary scatterer affects sidelobe lavel of elevation axis of offset parabolic antenna depending on angle and location of arbitrary structure.