• Journal of Korea Society of Industrial Information Systems
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• v.4 no.4
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• pp.111-116
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• 1999

In this paper, the electromagnetically coupled microstrip dipole antenna by adapting one parasitic metal-strip(dipole) between the microstrip transmission line open end and the radiating microstrip dipole antenna is presented for the bandwidth improvement The microstrip dipole antenna is simulated using Ensemble 51 simulation package The effects of varying several physical parameters, such as the lengths of radiating dipole and parasitic dipole and the width of parasitic dipole are investigated The bandwidth behavior of the 3-layer optimum antenna is compared with that of 2-layer antenna without the parasitic dipole. Experimental result for the obtained broadband performance is presented and discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.81-82
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• 2016

In this paper, a design method for a compact log-periodic half-bow-tie dipole array antenna for an operation in UWB band is studied. The proposed antenna is miniaturized by using half-bow-tie shaped dipole elements instead of strip-type dipole elements, which are commonly used in general log-periodic dipole array antenna, and by reducing the element spacing. The effects of the flare angle of the half-bow-tie elements and the element spacing on input reflection coefficient and realized gain characteristics of the proposed log-periodic antenna are analyzed. The optimized antenna is designed on FR4 substrate, and it operates in the frequency band of 3.05-13.96 GHz for a VSWR < 2, which assures the operation in the UWB band.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.115-118
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• 2000

본 논문에서는 4 개의 다이폴 소자로 구성한 4 섹터 지향성 절환 원형 배열 다이폴 안테나의 기본 특성을 검토하고 있다. 안테나의 방사 지향성이 순차적으로 4 섹터 절환이 가능하도록 하기 위해 급전 및 무급전 소자를 적절히 이용하고 있으며, 무급전 소자의 유도 전류에 의한 원형 배열 안테나의 특성 개선을 위해 급전 소자를 제외한 나머지 소자들을 단락 또는 개방시켜 방사 지향성 및 이득 특성 등을 계산하고 있다.

• Proceedings of the KAIS Fall Conference
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• 2005.05a
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• pp.140-142
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• 2005

본 논문에서는 900MHz대역에서 전방향성 특성을 갖는 RFID tag용 다이폴 안테나를 설계하였다. 전방향성 특성을 얻기 위해 두 개의 다이폴 안테나를 대각으로 위치하고 $90^{\circ}$의 위상차를 주어 급전하였다. 시뮬레이션 툴을 이용한 결과 안테나의 이득은 1.78dB이었으며, E-plane 과 H-plane 모두 전방향성 특성을 보였다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.1
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• pp.23-32
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• 2008

In the VHF range, active antennas are widely used for wideband applications due to their small size. Active antenna consists of antenna elements and amplifiers, which are directly connected to each other. Gain and noise-figure characteristics are very important for good sensitivity performance, because it is located at the front end of a receiving system. In this study, we developed an active dipole antenna with 5:1 bandwidth(100${\sim}$500 MHz), which consists of a dipole antenna and a P-HEMT amplifier. To obtain required performances, the antenna and the amplifier should be designed simultaneously. In order for that, we introduced an equivalent port concept to model the 1-port dipole antenna as an equivalent 2-port system. Using the proposed equivalent port, the performance of the active dipole antenna was simulated by the ADS. In order to measure the gain and noise-figure characteristics of the antenna, we utilized the same concept of the two-port equivalent impedance model. The measurement results for typical gain, NF and VSWR in the required frequency band were 8dBi, 9dB and 1.7:1, respectively. The radiation patterns at the principal planes were same as the typical radiation pattern of a dipole antenna. By comparing the simulation results with measured ones, it is confirmed that the proposed methods works well.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.4
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• pp.805-810
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• 2014

In this paper, the characteristics of a series-fed dipole pair antenna with an end-aligned strip pair director are studied. In the proposed SDP antenna, two strip dipole antennas with different lengths and a ground reflector are connected trough a coplanar stripline. The strip pair director placed above the second dipole element are two rectangular-shaped strips and is aligned at the ends of the two arms of the second dipole. The variations on the antenna performance for different lengths and widths of the director are analyzed, and optimal design parameters for the enhancement of the bandwidth are obtained. The optimized SDP antenna is fabricated on an FR4 substrate, and the experimental results show that the antenna has a frequency band of 1.65-2.95 GHz for a VSWR < 2, which shows enhanced bandwidth compared to the conventional SDP antenna.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.3
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• pp.497-502
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• 2014

In this paper, a design method for a broadband planar dipole antenna for terrestrial digital television (DTV) reception is studied. The dipole is modified to half bow-tie type for size reduction. The balun between feeding microstrip line and coplanar strip (CPS) line is implemented with a rectangular patch inserted along the center of the CPS line. The proposed antenna is the structure of dual resonances, one is due to the dipole and the other is due to the CPS line attached by the balun. The effects of various geometrical parameters on the antenna performance are examined, and the antenna is designed for terrestrial DTV band (470-806 MHz). The prototype antenna is fabricated on an FR4 substrate with a size of $95mm{\times}178mm$, and tested experimentally to verify the results of this study.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.11
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• pp.1207-1215
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• 2003

In this paper Log-Periodic Bent Dipole Antenna(LPBDA), which is composed of bent dipole elements instead of dipole elements, is proposed to reduce the size of Log-Periodic Dipole Antenna(LPDA). LPBDA for the operating frequency band of 1 ㎓∼3 ㎓ is designed and its radiation characteristics are analyzed by the moment method, and compared with radiation characteristics of LPDA. It is shown that although LPBDA decreases in size by about 20 %, radiation characteristics of LPBDA are similar to radiation characteristics of LPDA. Calculated results show good agreement with measured results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.7A
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• pp.678-682
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• 2011

In this paper, a compact log periodic dipole array (LPDA) antenna operating from 1 to 6 GHz is studied. Inverted-L shaped dipole elements are used to miniaturize the lateral size of an LPDA antenna and the spacing factor is also decreased to reduce the total length of the LPDA antenna. As the top-loading length of the inverted-L shaped dipole elements is increased, the width of the LPDA antenna is decreased but the bandwidth and the gain of the antenna are decreased. The fabricated compact LPDA antenna is printed on FR4 substrate With a dielectric constant of 4.4 and a thickness of 1.6 mm, and its size is reduced to 32% in width and 49% in length compared to a standard LPDA antenna.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.155-160
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• 2021

In this paper, we investigated the aptness of embroidered textile dipole antenna as a wearable antenna. We designed an 2.45GHz ISM band embroidered textile dipole antenna on polyester textile. We investigated its characteristics depends on 3 variables, thickness of textile(ttextile), distance between textile and surface of body(gbody) and conductance of surface of body(𝜎body). Thickness of textile(ttextile) was affecting on the antenna resonance frequency(fo). As the conductance of surface of body(𝜎body) was increased the antenna resonance frequency(fo) and the antenna gain were increased slightly. The increment of the distance between textile and surface of body(gbody) caused relatively large increment of the antenna resonance frequency(fo) and the antenna gain. From the results, in the case of designing an embroidered textile dipole antenna as a wearable antenna we should consider carefully the two variables, distance between textile and surface of body(gbody) and thickness of textile(ttextile). Due to its large variation, the distance between textile and surface of body(gbody) may be a technical barrier in designing embroidered textile dipole antenna.