• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.250-254
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• 2002

In this paper, we design an optimized planar array structure with triangular lattice for side-lobe reduction using a genetic algorithm. A constraint optimization is implemented by optimally removing some outer array elements far from the array center. It is shown that only the proper array shape without optimizing the magnitudes and phases of each array antenna can give low side-lobe level with a slight main beam broadening.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.542-545
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• 2003

An microstrip array antenna is designed based on the Sierpinski equilateral triangular patch. The Sierpinski geometry is composed of 3 equilateral triangular patch and is easy to generate a circular polarization by sequential rotation array techniques. This 1${\times}$3 Sierpinski equilateral triangular patch antenna is extended to 8${\times}$8 array antenna for satellite broadcasting receptions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.2
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• pp.415-421
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• 2005

The radiating or receiving characteristics of array elements (i.e., antennas) are changed from those of isolated elements due to mutual coupling effects and the array performance becomes different from those originally designed by assuming isolated elements. The effects of mutual coupling on the performance of a rectangular array with triangular grid geometry of dipoles above a ground plane are discussed with respect to element pattern. The concept of element gain function is used to examine the effects of mutual coupling on the array performance in terms of sidelobe level in the uniformly spaced and space-tapered rectangular arrays with triangular grid geometry of dipoles. It was shown that the sidelobe performance improved in the space-tapered array compared to the uniformly spaced array in the presence of mutual coupling effects. Computer simulation results are presented.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1598-1603
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• 2003

A microstrip array antenna is designed and tested for satellite broadcasting receptions. The Sierpinski equilateral triangular patch and SSFIP(slot­strip­foam­inverted patch) structures are used. The Sierpinski geometry is composed of 3 equilateral triangular patch and is easy to generate a circular polarization by sequential rotation array techniques. This 1${\times}$3 Sierpinski equilateral triangular patch antenna is extended to 8${\times}$2 array antenna for satellite broadcasting receptions. The measurement results of the reflection coefficients and the radiation patterns of the manufactured array antenna show good agreements with the simulation results.

• Journal of IKEEE
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• v.24 no.2
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• pp.372-377
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• 2020

This paper is based on the triangular inset patch antenna as the basic structure, and the array structure is the twin tree form to improve the antenna's main lobe gain and reduce the side lobe gain. A twin tree structure was implemented by placing two identical trees of 2-4-6 arrays of triangular inset patches side by side. The parametric analysis confirmed that the gap between tree structures arranged side by side is most effective for impedance matching. The fabricated antenna has a gain of 16.74 dBi at 24.15 GHz, and the beam width of the main lobe is 22° in the E-plane and 6° in the H-plane. The antenna size was 125 mm × 50 mm, and a Taconic TLC substrate with a dielectric constant of 3.2 was used. Although the main lobe gain is improved over the twin tree structure, The directivity in the beam pattern due to the mutual interference of the two tree array structure can be improved.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.49-52
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• 2003

A microstrip array antenna is designed and tested for satellite broadcasting receptions. The Sierpinski equilateral triangular patch and SSFIP(slot-strip-foam-inverted patch) structures are used. This 1$\times$3 Sierpinski equilateral triangular patch antenna is extended to 8$\times$2 array antenna for satellite broadcasting receptions. The measurement results of the reflection coefficients and the radiation patterns of the manufactured array antenna show good agreements with the simulation results.

• Bulletin of the Korean Mathematical Society
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• v.36 no.2
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• pp.273-285
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• 1999

In this paper we establish the weak law of large numbers for randomly weighted partial sums of random variables and study conditions imposed on the triangular array of random weights {$W_{nj}{\;}:{\;}1{\leq}j{\leq}n,{\;}n{\geq}1$} and on the triangular array of random variables {$X_{nj}{\;}:{\;}1{\leq}j{\leq}n,{\;}{\geq}1$} which ensure that $\sum_{j=1}^{n}{\;}W_{nj}{\mid}X_{nj}{\;}-{\;}B_{nj}{\mid}$ converges In probability to 0, where {$B_{nj}{\;}:{\;}1{\;}{\leq}{\;}j{\;}{\leq}{\;}n,{\;}n{\;}{\geq}{\;}1$} is a centering array of constants or random variables.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.7
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• pp.709-720
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• 2014

In this paper, we studied miniaturization of LPDA(Log-Periodic Dipole Array) antenna used for VHF and UHF bands. To miniaturize the LPDA antenna, in this study, the radiation elements in a low frequency were changed into a triangular meander structure which has small current cancelation effect at feed part. For the triangular meander structure, an isosceles triangular and right triangular meander structures were proposed and the LPDA antennas were miniaturized by using the two meander structures. Also, the simulated and measured results were compared for the two miniaturized LPDA antennas. As a result, the isosceles triangular meander and right angle triangular meander structure applied LPDA antennas were reduced up to 60.5 % and 72.4 % compared a basic LPDA antenna, respectively. Consequently, we confirmed that the triangular meander structure is suitable for miniaturization of a LPDA antenna.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.389-393
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• 2000

마이크로스트립 안테나는 다양한 장점에 의해 배열 안테나로서 각광을 받고 있다. 하지만 표면 전파에 의한 음영각 발생 및 이에 따른 조향각이 제한된다는 단점을 가지고 있다. 본 논문은 이러한 문제점들을 해결하기 위하여 radome이 올려진 cavity-backed 단일 방사 소자들을 showed array 구조론 통해 해결하는데 초점을 두었으며, 알고리즘에 대한 설명과 본 구조를 이용하여 실제 성능의 개선을 가져 올 수 있음을 보이고자 한다.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.824-828
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• 2000

Prior to the downloading of the NC codes to a machining center, the NC tool-path can be verified in a computer. The Z-map is one of the tools for the verification of NC tool-path. The Z-map is a two dimensional array in which the height values of the Z-axis direction vectors are stored. The Z-axis direction vectors are arranged in a rectangular grid pattern on the XY plane. The accuracy of the simulation comes from the grid interval. In the rectangular Z-map, the distances between the grid points are different. The distance in diagonal direction is larger than those in X or Y axis directions. For the rendering of the Z-map, a rectangular grid is divided into two triangular facets. Depending on the selection of a diagonal, there are two different cases. In this paper, triangular Z-map, in which the Z-axis direction vectors are arranged in a triangular grid pattern on XY plane, is proposed. In the triangular Z-map, the distances between grid points are equal. There is no ambiguity to make triangular facets for the rendering.