• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.7B
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• pp.895-900
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• 2001

본 논문에서는 하나의 급전선을 갖는 원형 섹터 마이크로스트립 안테나를 사용하여 서로 수직한 편파 특성을 갖는 이중주파수 안테나를 설계하였다. 여기되는 모드 및 주파수를 공진기 모델을 사용하여 계산하였으며, 반경과 섹터 각도를 파라미터로 하여 여기되는 두 주파수를 설계할 수 있었다. 약 2GHz 대역에서 동작하는 안테나를 제작하여 안테나의 특성을 측정하였다. 안테나의 반경을 고정하고 섹터 각도를 75$^{\circ}$에서 120$^{\circ}$까지 변화시켜, 여기되는 두 주파수의 비가 1.08에서 1.518까지 변하는 것을 볼 수 있었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2816-2822
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• 2014

In this paper, a wideband loop antenna for UWB applications is studied. The structure of the proposed wideband loop antenna is a circular loop antenna with appended circular sectors to obtain an ultra-wideband characteristic. The circular sectors are used instead of conventional triangular sectors to match with the 50 ohm feed line. Optimal design parameters are obtained by analyzing the effects of the gap between the circular sectors and the radius of the circular loop on the input reflection coefficient and gain characteristics. The optimized wideband loop antenna is fabricated on an FR4 substrate with a dimension of 41 mm by 41 mm. Experiment results show that the proposed antenna has a frequency band of 3.1-11.0 GHz for a VSWR < 2.25, which assures the operation in the UWB band. Measured gain ranges 1.3-5.3 dBi 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.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.812-816
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• 2001

In this paper we designed a dual-frequency circular sector microstrip antenna fed microstrip line with orthogonal polarization. The operating frequencies and polarization characteristics of the proposed antenna is calculated by using a cavity model. The antenna operating at about 1.87 GHz and 2.42 GHz is fabricated and its S-parameters and radiation patterns are measured.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.10
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• pp.1845-1851
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• 2016

In this paper, a design method for a wideband square loop antenna for Digital TV applications is studied. The proposed loop antenna is a square loop antenna combined with circular sectors to connect with central feed points. The square loop is used instead of the circular loop in order to miniaturize the antenna size. The input reflection coefficient and gain characteristics of the proposed antenna are analyzed to match with the 75 ohm port impedance for DTV applications. The effects of the gap between the circular sectors and the length of the square loop on the input reflection coefficient and gain characteristics are examined to obtain the optimal design parameters. The optimized antenna is fabricated on an FR4 substrate, and the experiment results show that it operates in the frequency band of 470-1,300 MHz for a VSWR < 2, which assures the operation in the DTV band.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.807-811
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• 2001

In this paper we proposed a dual-frequency circular sector microstrip antenna with orthogonal polarized modes and high isolation between the two feeding ports. And then we designed a transceiver operating at 5.6 GHz for transmitting and at 5.5 GHz for receiving. The good isolation provided by the proposed antenna is used as the basis for the transmit-receive filtering of transceiver. The operating frequencies and polarization characteristics of the proposed antenna is calculated by using a cavity model. The 5-parameters and radiation patterns of the antenna are measured. A power amplifier and a low noise amplifier are designed and integrated with antenna to make a transceiver, which has about 13dB transmitting gain and about 8㏈ receiving gain.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.187-190
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• 2001

In this paper we designed a dual-frequency circular sector microstrip antenna fed microstrip line with orthogonal polarization. The operating frequencies and polarization characteristics of the proposed antenna is calculated by using a cavity model. The antenna operating at about 1.87 GHz and 2.42 GHz is fabricated and its S-parameters and radiation patterns are measured.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.49-50
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• 2014

In this paper, a wideband loop antenna for UWB applications is studied. The proposed wideband loop antenna consists of a circular loop and circular sectors. Circular sectors with a ultra-wideband characteristic are used to connect the circular loop and the center feed points. Optimal design parameters are obtained by analyzing the effects of the gap between the circular sectors and the radius of the circular loop on the input reflection coefficient and gain characteristics. The optimized wideband loop antenna is fabricated on an FR4 substrate with a dimension of $41mm{\times}41mm$. Experimental results show that the antenna has a desired UWB characteristic with a frequency band of 3.1-11.0 GHz for a VSWR < 2.25.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.8
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• pp.1492-1497
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• 2017

In this paper, a design method for a CPW-fed wideband loop antenna for indoor digital TV applications is studied. The proposed loop antenna consists of a square loop and two circular sectors which connect the loop with central feed points, and the CPW feed line is inserted in the lower circular sector. The CPW feed line is designed to match with the 75 ohm port impedance for DTV applications, and the ground slots are etched in order to improve the impedance matching in the middle frequency region. The effects of the gap between the circular sectors and the location and dimension of the ground slots on the input reflection coefficient and gain characteristics are examined to obtain the optimal design parameters. The optimized antenna is fabricated on FR4 substrate, and the experiment results show that it operates in the frequency band of 463-1,280 MHz for a VSWR < 2, which assures the operation in the DTV band.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.4
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• pp.386-392
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• 2002

This paper presents a basic characteristics of 4-element circular array dipole antennas for 4-sector beam steering. The coupled integral equations for the unknown current distributions on dipole elements are derived and solved by applying Galerkin's method of moments. The parasitic elements have been used to increase the directional gain and the beam is steered electronically either by sswitching between the parasitic elements or switching the position of the active element. The parasitic elements are switched short-circuited or open-circuited as required to steer a directional beam. In order to verify the theoretical analysis, the radiation pattern was compared with experiments.