• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.4
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• pp.653-660
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• 1998

The purpose of this paper is to analyze the electromagnetic field characteristics of microstrip array antenna with the FDTD(finite difference-time domain method). Finite difference equations of Maxwell's equations are defined in rectangular coordinate systems. To simulate the unbounded problem like a free space, the Mur's absorbing boundary condition is also used. After modeling the microstrip array antenna with the grid structure, the transient response of the field distribution is depicted in the time domain.

• Journal of Digital Contents Society
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• v.10 no.3
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• pp.389-393
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• 2009

In this paper, the single patch microstrip antenna and gap coupled broadband microstrip patch antenna using FDTD(Finite Difference Time Domain method) are analyzed. Mur's 2nd absorbing boundary condition to minimize reflected wave is applied. Return loss, voltage standing wave ratio, and input impedance by the length and width of driving patch, the length and width of parasitic patch, and the distance between driving patch and parasitic patch have been analyzed. Design parameters and radiation patterns of broadband antenna have been also shown.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.3
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• pp.533-540
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• 1999

In this paper, a microstrip antenna is designed using a rectangular patch. To find characteristics of the antenna, computer simulations of the rectangular single microstrip patch antenna are performed with changing width and feed line. And we found characteristics of RHCP using axial ratio. Through the results, we found that the Finite Difference Time Domain(FDTD) method is an effective method for designing microstrip patch antenna. According to simulation the resonant point has been found it in the frequency received from GPS satellite. And these results were in relatively good accordance with the measured values.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.8
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• pp.1740-1746
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• 1997

In this paper, a waveguide-fed slot-coupled microstrip antenna is proposed as enhanced feeding structure of microstrip antenna and an analysis is presented. The presence of dielectric substrate between a stripand a slot is explicitly taken into account in this analysis. The evaluation of the antenna characteristics is carried out using the method of mements and the spectral domain approach in terms of the electric current distribution on the strip and the magnetic current distribution on the slot. From the results, we can conclude that the proposed structure is adequate for array antennas, due to ease of mass porduction and enhanced anteena performance.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.3
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• pp.173-173
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• 2004

In this paper, a wideband two-layer H-shaped microstrip antenna for WLAN is designed. To increase the bandwidth of microstrip patch antenna a configuration of stacked type using parastic element is used. Furthermore, to reduce the size of microstrip patch antenna, two techniques are employed . the first one is H-shaped patch type and the second one is that the main radiator and parastic patch are shorted to the ground plane using ten shorting posts. The antenna bandwidth and radiation characteristics are calculated by ENSEMBLE ver. 5.0 simulation software, and compared with the experimental results. Experiment results show that the bandwidth of antenna in 740㎒ centered at 5.46㎓(13.5%), which is close agreement with the calculations, 770㎒(13%). Also, the antenna size can be reduced by 71.5% compared with the half wavelength rectangular microstrip antenna using the same substrate at the same frequency.

• Journal of Korea Society of Industrial Information Systems
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• v.9 no.2
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• pp.74-80
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• 2004

This paper presents analysis and design for Microstrip antennas using FEM (Finite Element Method). For the miniaturization of the antennas, dielectric substrate (ε/sub r/=4.6) and rectangular patch structure are used. The proposed Microstrip antennas are simulated using commercial simulator (HFSS). The results of the simulation are presented and compared with characteristics of each array type. Especial, the proposed antennas can be applied to the design of various communication systems for 2.4 GHz band.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.8 s.338
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• pp.41-46
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• 2005

Microstrip open-end and linear resonator are analyzed by method of moment (MoM) taking the entire-domain current distribution, found in literature, along the transverse direction of microstrip line. A transverse correlation function which incorporates permittivity, thickness and width of the line is derived. Numerical examples are investigated and compared with the available other data and methods in order to give the validity of the proposed method. It is found that the proposed method can generate more accurate results than the conventional methods.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.948-957
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• 2001

We proposed a novel feed structure for a broadband circular slot antenna. The proposed antenna has a circular slot, a radiating element, and a novel microstrip feed structure which is composed of a 50 Ω microstrip feedline and a circular-shaped microstrip patch. This antenna is analyzed and optimized by using the finite difference time domain (FDTD) method. The impedance bandwidth of optimized antenna is 1.94 octave that is much broader than the conventional microstrip slot antennas.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.345-351
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• 2000

In this paper, we design and analyze a Ka-band microstrip line to rectangular waveguide transition using the expanding-cell FDTD method. The transition under investigation consists of a ridged waveguide, microstrip line, and $\lambda$/4 Chebyshev impedance transformer. To improve the accuracyand efficiency, the expanding-cell FDTD method is applied to analyze the characteristics of a ridged waveguide impedance transformer. To verify the accuracy of the expanding-cell FDTD method, S parameters of the analyzed transition are compared with those of experimental data. The efficiency of the present approach is verified by comparing the computational time for expanding-cell and that for fine cell. The relation between the number of step and operation bandwidth is analyzed by comparing the characteristics of four and three step Chebyshev waveguide impedance transformer.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.1
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• pp.10-16
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• 1995

The E-polarized scattering problems by a perfect conductor strip grating are analyzed by the method of moments. For an E-polarization the induced surface current density is expected to blow up at the strip both edges. Then the induced surface current density on the strip is expanded in a series of multiplication of Ultraspherical ploynomials with zeroth order and functions with appropriate edge boundary condition. The numerical results for current density and reflection cofficient are compared with other functions, it is shown that numerical results better improves the convergence of the moment method soulutions with general incident angles than the existing several other functions. The sharp variation points in the magnitude of geometric-optical reflection coefficient can be moved by varying the incident angle, strip width, and strip spacing.