• Journal of the Korea Society of Computer and Information
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• v.19 no.10
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• pp.71-79
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• 2014

In this paper, the microstrip array antenna is studied to replace the parabolic antenna in the direct satellite reception. A microstrip array antenna has been used in extremely limited area, but if it is applied to practical life like a direct satellite reception antenna, we expect that it will be used in various way. First of all, if we use a microstrip array antenna for a direct satellite reception antenna, it should be guaranteed characteristics of broadband frequency. Therefore, the goal of this paper is designing technique an antenna which guarantees broadband frequency band for a direct satellite reception. In this paper, the proposed microstrip antenna is fed by orthogonal two feed lines to a rectangular patch and a sequentially rotated feeding technique is designed proposed for a good axial ratio in broadband frequency band. The rectangular patch is designed to satellite reception band, and the width and length are W=L=8.9 mm ($0.352{\lambda}o$) respectively. The antenna's ground plane has dimensions of $250{\times}250mm$. The experimental results verify that the proposed antenna had the axial ratio of above 1dB broader than that of the conventional feeding antenna. In order to verify the performance, a $8{\times}8$ array having two pairs was fabricated and tested. The maximum gain is 20.8 dB, the sidelobe level confirm less than -10 dB. It is verified by link budget calculation that C/N=6.7 dB can be obtained for domestic use if this proposed antenna is used in Koreasat reception system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.70-73
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• 2012

In this paper, we introduce a design method for a quasi-Yagi antenna (QYA) with broadband characteristics of an impedance bandwidth ratio of > 2 : 1 and a gain of > 4 dBi. The QYA is fed by a microstrip line fabricated on a coplanar strip line and it consists of 3 elements; a planar dipole, a nearby director close to the dipole, and a ground plane reflector. By placing a rectangular patch-type director with large width near to the dipole driver, broadband characteristics are achieved. An optimized 3-element QYA for operation over 1.6-3.5 GHz (bandwidth ratio 2.2 : 1) is fabricated on an FR4 substrate with a size of $90mm{\times}90mm$ and tested experimentally. The results show an impedance bandwidth of 1.56-3.74 GHz (bandwidth ratio 2.4 : 1) for VSWR < 2, a peak gain of 4.41-6.53 dBi, and a front-to-back ratio (FBR) > 13.6 dB within the bandwidth.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1189-1196
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• 2015

In this paper, a microstrip-fed multiband monopole antenna for GPS(Global positioning system)/WiMAX(:Worldwide interoperability for microwave access)/WLAN(Wireless Local Area Networks) for applications was designed, fabricated and measured. The proposed antenna is based on a microstrip-fed structure, and composed of two rectangular double rings and L strips pair and then designed in order to get triple band characteristics. To obtain the optimized parameters, we used the simulator, Ansoft's High Frequency Structure Simulator(HFSS). The proposed antenna is made of $27.0{\times}54.0{\times}1.0mm3$ and is fabricated on the permittivity 4.4 FR-4 substrate. The experiment results shown that the proposed antenna obtained the -10 dB impedance bandwidth 300 MHz (1.325~1.625 GHz), 400 MHz (2.275~2.675 GHz), and 600 MHz (3.15~3.75 GHz) covering the GPS/WiMAX/WLAN bands. Also, the proposed antenna measured gain and radiation patterns characteristics for required operating bands.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.9
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• pp.841-848
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• 2016

In this paper, a microstrip-fed dual-band monopole antenna with DGS(: Defected Ground System) for WLAN(: Wireless Local Area Networks) applications was designed, fabricated and measured. The proposed antenna is based on a microstrip-fed structure, and composed of two strip lines and DGS structure and then designed in order to get dual band characteristics. We used the simulator, Ansoft's High Frequency Structure Simulator(: HFSS) and carried out simulation about parameters W2, L10, W3, and DGS to get the optimized parameters. The proposed antenna is made of $21.0{\times}36.0{\times}1.6mm3$ and is fabricated on the permittivity 4.4 FR-4 substrate. The experiment results are shown that the proposed antenna obtained the -10 dB impedance bandwidth 700 MHz(2.10~2.80 GHz) and 1,780 MHz(5.02~6.80 GHz) covering the WLAN bands. Also, the measured gain and radiation patterns characteristics of the proposed antenna are presented at required dual-band(2.4GHz band/5.0GHz band), respectively.

• Journal of Advanced Navigation Technology
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• v.17 no.2
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• pp.171-176
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• 2013

A microstrip-fed miniaturized folded-slot antenna that is cut at the finite ground plane edge for the size reduction is proposed as a ZigBee module operating in the 2.4 GHz frequency band, as specified by the IEEE standard 802.15.4. The antenna is fabricated within space limited to $35mm{\times}9mm$ on a $35mm{\times}35mm$ substrate, which is about the PCB size of a typical wireless ZigBee module. The measured impedance bandwidth and antenna gain are 2.37~2.49 GHz and 2.4 dBi respectively. The measured radiation patterns are similar to conventional folded-slot antennas and are also stable across the pass band. These properties and its compact structure help in making the antenna suitable for ZigBee module.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.2 s.117
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• pp.143-150
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• 2007

A meander slot antenna with open-end fed by a microstrip line which can be used at 400 MHz ISM band is newly proposed. The main difference between the proposed slot antenna and the previous slot antenna is the introduction of the open-end to miniaturize the previous meander slot antenna in the space restricted within narrow limit. In order to check the validity of the proposed antenna, the resonant frequency and radiation pattern of the proposed antenna have been simulated and examined. Good agreements between simulated results and measured results have been observed.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1049-1056
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• 2017

In this paper, a microstrip-fed dual-band monopole antenna with two arc-shaped lines for WLAN(: Wireless Local Area Networks) applications was designed, fabricated and measured. The proposed antenna is based on a microstrip-fed structure, and composed of two arc-shaped lines and then designed in order to get dual band characteristics. We used the simulator, Ansoft's High Frequency Structure Simulator(: HFSS) and carried out simulation about parameters L2, L5, and with/without slit to get the optimized parameters. The proposed antenna is made of $13.0{\times}34.0{\times}1.0 mm^3$ and is fabricated on the permittivity 4.4 FR-4 substrate($12.0{\times}34.0{\times}1.0mm^3$). The experiment results are shown that the proposed antenna obtained the -10 dB impedance bandwidth 360 MHz (2.29~2.65 GHz) and 1,245 MHz (4.705~5.95 GHz) covering the WLAN bands. Also, the measured gain and radiation patterns characteristics of the proposed antenna are presented at required dual-band(2.4 GHz band/5.0 GHz band), respectively.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.5
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• pp.163-168
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• 2019

In this paper, We investigated the effects of the transparency variations from 0% to 90.7% on meshed SF-MPAA(Series Fed Microstrip Patch Array Antenna). For this, we designed SF-MPAA in 3 cases that is meshed radiation patches, meshed GND, and meshed radiation patches plus GND. And we investigated the characteristics of SF-MPAA depend on the variations of transparency in each case. In the case of meshed radiation patches, the gain decreased by 18.8% and the operating frequency is lower by 5.5%. In the case of meshed GND, the gain decreased by 15.4% and the operating frequency is lower by 5.56%. In the case of meshed radiation patches plus GND, the gain decreased by 31.94% and the operating frequency is lower by 7.6%. However, the bandwidth and the SLL(Side Lobe Level) did not show apparent tendency on the the variations of transparency.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.10
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• pp.1338-1343
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• 2018

MIMO(Multiple Input Multiple Output) slot antenna that operates on the dual WiFi band(2.401~2.495GHz, 5.18~5.825GHz), in this paper, was studied. The basic theory for the slot design is based on the coupling between adjacent slot, and slots are fed by the each microstrip lines. Two slot antennas for the MIMO operation are located on the left and the right side of top of the metal notebook, and grounds between a notebook and two microstrip feeding lines are connected. Measurement of return loss showed under -6dB on entire design band, and isolation was below than -30dB. Radiation efficiency, average gain and peak gain for the left and the right slot were measured in the anechoic chamber, and showed good performances as 57.25%, -2.42dBi, 5.64dBi and 55.35%, -2.61dBi, 6.42dBi for the 2.4GHz band and 55.89%, -2.58dBi, 7.3dBi and 53.79%, -2.8dBi, 7.54dBi for the 5GHz band.

• The Journal of the Acoustical Society of Korea
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• v.18 no.4
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• pp.11-16
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• 1999

In this paper, we designed and fabricated QMSA(Quarter-Wavelength Microstrip Antenna) for 850MHz band on the CGP-500 PTFE substrate(by CHUKOH company) with ε/sub r/=2.6, H=1.6mm(±0.08), where width of the radiation patch is .identical with that of the ground plane. A well matched feed point was obtained by experiments and this QMSA was fed by using prove feed method. The resonant frequencies and the return losses were mcasured by cutting the gap L₃ between the radiation patch and the ground plane, with a 5mm cutting length, step by step. As a result, we found that the measured return losses were decreased and the resonant frequencies were increased when the gap L₃ was shorter, especially under 10mm, unlike we had expected.