• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.2
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• pp.105-116
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• 1996

The design and analysis of the transversely fed EMC(electromagnetically coupled) microstrip dipole have been accomplished by using the integral equation and MOM(method of moment)in frequency domain in order to find the current distribution of the dipole. In this study, we proposed the possibilities for design and analysis of EMC micro-strip dipole array antenna by means of calculating the current distribution of each dipole directly using the FDTD(finite difference time domain) method. In this case, we applied the formulation which is the finite difference expression of the Maxwell's integral equation. From the current distribution of each dipole, we calculated the far field electric component and showed that the calculation process and running time was reduced with respect to the method which calculates the radiation field with surface electric and magnetic current density.

• Journal of the Korean Society for Railway
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• v.5 no.1
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• pp.26-31
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• 2002

The more sophisticated patterns of propagation model is presented in this paper, which includes three different source characteristics (spherical, cosine and dipole). The spherical, cosine and dipole radiation characteristics compared, and sound event level and the maximum sound level are calculated by experiment and calculation. It is shown that patterns of propagation have dipole characteristics for low speed range (below about 150Km/h) at electric multiple system. We know that push-pull high speed system has cosine characteristics of noise propagation at low speed range (below about 200Km/h).

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.204-209
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• 2001

The more sophisticated patterns of propagation model is presented in this paper, which includes three different source characteristics (spherical, cosine and dipole). The spherical, cosine and dipole radiation characteristics compared, and sound event level and the maximum sound level are calculated by experiment and calculation. It is shown that patterns of propagation have dipole characteristics for low speed range (below about 150Km/h) at electric multiple system. We know that push-pull high speed system has cosine characteristics of noise propagation at low speed range (below about 200Km/h).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.3 s.118
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• pp.273-281
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• 2007

This paper presented design for a dipole antenna operated at 900 MHz band RFID tag, and antenna performance varied by the sticked material was experimentally evaluated. When dipole antenna was sticked by the material having a difffrent electric characteristic such as dielectric material, fero-magnetic material and conductor, variations of antenna return loss and radiation pattern according to the sticked material kinds, size, and height between antenna and the sticked plate were experimentally observed and evaluated. When antenna was sticked by dielectric surface, the measured return loss and radiation pattern by affection of different dielectric permittivity ratio showed resonant frequency shift of about 40 MHz and relative attenuation of 1 dB to 3 dB. Even though frequency shift by size variation of the sticked plate was observed, the measured radiation pattern of dipole antenna located on the sticked plate was similar with one without backside plate. In the case of conductor or fero-magnetic material as the sticked ground plate, because of frequency shift and phase difference by distance between dipole antenna and the sticked ground plate, amplitude decrease of radiation pattern at 910 MHz was observed about 5 dB above.

• Journal of electromagnetic engineering and science
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• v.10 no.3
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• pp.79-85
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• 2010

In this paper, a directive antenna design with a combination of electric-magnetic radiators for an radio frequency identification(RFID) system is presented. To generate a directive antenna radiation pattern, a structure combining a dipole and loop antenna is presented. A reader antenna and tag antenna are proposed for the RFID system. For the reader antenna, the frequency bandwidth defined by $S_{11}$<-10 dB is approximately from 820~990 MHz. The forward and backward gain differences are 1.5~2 dBi. For the tag antenna, the frequency bandwidth is approximately from 860~920 MHz with a maximum gain of 3.58 dBi at 910 MHz. In both cases, directive radiation characteristics are observed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.4
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• pp.531-536
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• 2003

In order to control the railway noise. we should know the radiation characteristic of the noise during the train passage Generally, the railway noise sources for conventional trains are classified by the rolling noise and power unit noise in tangent track. In this Paper. we describe on a train model that is considered to be a row of point sources to calculate the radiation characteristic The calculation results are compared with short distance measurement of three kinds of trains (EMU, Mookungwha, Saemaul). It is shown that the radiation characteristic of the rolling noise that is major noise source of electric multiple unit is dipole type. We know that characteristic of the engine noise is radiated as the cosine type.

• Geophysics and Geophysical Exploration
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• v.4 no.2
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• pp.45-54
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• 2001

A three-dimensional finite difference time-domain modeling algorithm based on staggered grid and considering transmitting and receiving antennas has been developed to simulate Ground Penetrating Radar (GPR) survey. This algorithm adopted the subcellular method to simulate the dipole antennas being used in GPR system and added resistors to reduce ringing caused by the reflections at the ends of an antenna. Comparison of the output voltages in the presence of the resistors for half-space said that the ringing and the amplitude of output voltage decreased as the number of resistors increased, and the antenna was designed based upon this result. Radiation patterns were derived to understand the distribution of electric field energy in the planes including or normal to the antenna. The electric field energy concentrated on vertical direction in the plane including antenna more than in normal plane.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.1
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• pp.9-16
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• 2009

In this paper, a method is proposed for the analysis of radiowave receiving characteristics of an ammunition with electric detonator. In this method, an ammunition with electric detonator is modelled as a receiving antenna with its gain obtained by computer simulation or measurement. The induced radiowave power is obtained by inserting the gain of the electric detonator in the antenna coupling formula. Radiowave receiving characteristics at very close distances are obtained by Treasuring the transmission coefficient between a half-wave dipole and the electric detonator model. Radiowave receiving characteristics of the electric detonator in a 105mm tank ammunition are obtained using the proposed method and the safety of the 900 MHz RFID reader on the detonator is assessed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3107-3113
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• 2014

We present a quantitative analysis of a dipole antenna and its characteristics from the viewpoint of quantum mechanics. The method makes use of a Maxwell equation used in an existing antenna propagation formula. This includes radiation resistance, input reactance, and antenna efficiency as functions of frequency and antenna length. Particular attention is paid to the Schr$\ddot{o}$odinger equation. We accomplish E-field and H-field analyses of a dipole antenna by combining the Maxwell and Schr$\ddot{o}$odinger wave equations. When comparing the existing Maxwell wave equation with the Schr$\ddot{o}$odinger wave equation, quantum-electric movement is more accurate than using the Maxwell wave equation alone.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.191-194
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• 2002

We analyzed radiation characteristics of dipole antenna in a lossy 9round with conducting object located above ground. Electric field integral equation is used to solve the problem. In this integral equation, GPOF(Generalized Pencil of Function) method is applied to derive the closed form of the electric field due to a current source. Surface current on a conductor is expanded with a well-known vector triangle basis function. The singular integration of a triangle patch is transformed to the non-singular integration by Duffy's method. This transformed non-singular integration is easily calculated by using one-dimensional Gaussian quadrature rule, instead of usual closed form evaluation.