• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1669-1676
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• 1993

In this paper, a thin-straight monopole antenna attached to a conducting box is analyzed using a moment method with the pocklington integral expression for the exact Green's function. A modeling of a conducting box is based on a Wire-Grid method for an efficient calculation procedure. A system of linear equation is obtained using the piecewise sinusoidal basis function. And a Junction basis function is enforcing to represent the physical current on the edge of the conducting box. Especially, the junction basis functions are overlapped for the current continuity preserving on the vertexes. Numerical results are obtained for the current distribution on the unified antenna/conducting box system, input impedance and radiation pattern. The results are compared with the known data.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.9
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• pp.912-918
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• 2003

In this paper, we designed and implemented the dual band monopole antenna for cellular CDMA(Code Division Multiple Access) and IMT-2000(International Mobile Telecommunication 2000) repeater. The antenna was designed by using 3D simulations program, HFSS(High Frequency Structure Simulator). Electrical characteristics were measured by using HP 8720C network analyzer and measured maximum S$\_$11/ was -10.9 dB for all frequency bands of interests in Cellular CDMA and IMT-2000. Simulation results for antenna gain at 859 MHz and 2027.5 MHz were 2.38 dBi and 4.02 dBi respectively with omni directional radiation pattern. The size of implemented antenna is compact and the antenna can be produced in low cost enough for commercialization.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.3 s.94
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• pp.260-269
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• 2005

In this paper, we propose a microstrip line fed printed monopole antenna which has an ultra-wideband characteristic. Proposed antenna can improve the bandwidth characteristic with the taper structure formed by modified ground plane and radiating element. Measured impedance bandwidth ratio of the antenna is more than 30:1; from the lower frequency of 0.89 GHz to the upper frequency of more than 30 GHz for VSRW$\leq$2. The antenna has conical radiation pattern that has low radiation gain to $\theta$=0$^{\circ}$ direction and higher radiation gains as $\theta$ increases.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.7
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• pp.763-768
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• 2015

In this paper, a microstrip patch antenna with arrow and ribbon shape for WLAN was designed and manufactured. The antenna was designed on a FR-4 substrate that has a thickness of 0.8mm and a dielectric constant of 4.4. The substrate size is $50{\times}40mm^2$. A commercially available tool was used for simulation to get the optimized parameters and the optimized values were obtained by finding the parameters that act sensitively to the performance of the antenna. The proposed antenna was produced using the optimized values, and characteristics of return loss, gain and radiation pattern in WLAN bands were measured.

• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.189-196
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• 2011

In order to subsitute for the normal mode helical wire antenna, bent monopole antenna combined with a helical structure is proposed as a kind of printed antenna. The antenna which can be operated at 418MHz has been simulated and designed by use of a commercial EM simulator Microwave Studio(MWS). It has been observed that the proposed antenna has good agreements between simulated results and measured results such as the return loss and the radiation pattern. The proposed antenna has been applied practically to the wireless remote controller operationg at 418MHz. It has been observed that the use of the proposed antenna result in similar antenna performance from view point of radiation power when compared with the use of the previous normal mode helical antenna.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.55-62
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• 2000

In this paper, cellularphone antenna was designed to be capable of being mounted on the circuit-board with co-planar feeding method. The designed antenna is fabricated by the following procedure : make the multi-layered dielectric ceramic($\varepsilon_{\tau}$=23) hexahedron($7.5mm\times4.5mm\times0.4mm$) and then produce λ/4 monopole radiation element with helical structure on the surface of the hexahedron. The results are as followings : Returnloss 27.36 dB, -10 dB bandwidth 76 MHz(3.97 %), H-plane average gain -9.43 dBd.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.165-169
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• 2011

In recent years mobile phone handset terminal has tended to have additional various functions and slim and light weight, and its internal space is getting smaller and narrower. According to complex parts, small and narrow inner space is caused not sufficient bandwidth and lower impedance. Moreover, additional polarization loss by the surrounding parts produces is lower effectiveness and increases difficulties for getting the antenna gain. For IFA is low profile structure based on the ILA(Inverted L Antenna) which is transformed from the monopole antenna. While this antenna has lots of advantages in internal antenna of mobile phone, it has some disadvantage of reduced bandwidth and gains compared with monopole antenna. In this paper, propose vlade hybrid antenna use for the coupling structure.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.8
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• pp.1322-1328
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• 2000

This paper presents the characteristics of complex antenna factors of monopole antenna for the measuring time-domain fields above the ground plane. The method of moments with Galerkin's procedure is used to determine the current distribution of the antenna. The monopole antenna with chip resistor is discussed to reduce the reflection at low frequencies. Numerical results show that the magnitude of the complex antenna factor for the monopole with chip resistor is 5.6 dB as large as that of the conventional monopole antenna. The characteristics of the modified complex antenna factor to use the antenna factor are also treated at low frequencies. To verify the theoretical analysis, experimental results are compared with theoretical ones.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.70-72
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• 2011

In this paper, Dual-band monopole antenna for MIMO system is proposed. At this time the FR-4 substrate was used as a dielectric is 4.4, the size of 83mm * 50mm * 1.6mm size 3mm, the width of the proposed antenna by a $50{\Omega}$ microstrip line feed, and, LTE in the frequency 746-787MHz, 1710-1755MHz has been designed to operate at the resonant frequency less than-10dB and showed a good return loss in the operation.

• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.925-930
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• 2018

In this paper, we present a low profile dual-microstripline-fed double 4-arrayed meander monopole antenna with a cross-type element back by separated four-segments mesh-type reflector. The cross-type element and separated four-segments mesh-type reflector leads to enhance radiation patterns and antenna gain characteristics. The measurement value of the proposed antenna show that it has dipole-like radiation pattern characteristics. The experimental peak gain of fabricated antenna is about 2.89 dBi, which presents relatively high gain characteristics for a low profile(small-size) one. This antenna can be applied mobile RFID(radio frequency identification) readers, small medical instruments, broadcasting and home-networking operations, and other low profile high-gain systems.