• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.6
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• pp.698-705
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• 2010

A vehicle antenna for AM, FM, TDMB, GPS systems was designed and implemented. Omnidirectional AM antenna was designed by ferrite turn style antenna. For the FM and TDMB antenna, folded monopole antenna which helical is folded was applied. GPS antenna for the bandwidth achievement was designed by trapezoidal microstrip patch that has air substrate. Receiving signal strengths by the measurement were presented for the AM, FM and TDMB antenna. AM signal strength was -65.7 dBm, this strength is almost as same conventional pole antenna as -63.4 dBm. It can be replaced conventional pole or glass antenna by the studied antenna. Signal strengths for FM and TDMB were -55.66 and -43.50 dBm at center frequency, they are 5~10 dB higher than conventional antenna. Measurements of bandwidth and gain for the GPS antenna showed 135 MHz under VSWR 2 : 1 and 4.31 dBi, gains over GPS band were 3~5 dB higher than ceramic patch antenna.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.105-113
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• 2009

In this paper, a vehicle antenna for AM, FM, TDMB, GPS systems was designed and implemented. AM antenna loaded into small space of shark shape was designed by ferrite turn style antenna. For the FM and TDMB antenna, folded monopole antenna which helical is folded was applied. GPS antenna for achieving characteristics both bandwidth and gain improvement was designed microstrip patch that has air substrate and fractal structure. Receiving signal strengths by the measurement were presented for the AM, FM and TDMB antenna. AM signal strength was -65.7dBm, this strength is almost as same conventional pole antenna as -63.4dBm. It can be replaced conventional pole or glass antenna by the studied antenna. Signal strengths for FM and TDMB were -55.66 and -43.50dBm at center frequency, they are 5~10dB higher than conventional antenna. Measurements of bandwidth and gain for the GPS antenna showed 135 MHz under VSWR 2 : 1 and 4.31dBi, gains over GPS band were 3~5dB higher than ceramic patch antenna.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.1
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• pp.155-161
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• 2007

This paper presents the design simulation, implementation, and measurement of a miniaturized PCS / Satellite DMB dual-band stacked mompole antenna with a parasitic patch for mobile communication terminals. A stacked helix is realized by using a via hole with height of 0.4 mm and a diameter of 0.35 mm to connect upper- and lower-layer helix sections for a reduction of the dimensions of the antenna. In addition the stacked helix chip antenna is interleaved with a parasitic patch to achieve two different radiation modes. The ratio of the first frequency and the second frequency vary with the geometrical parameter of the parasitic patch. The fabricated antenna uses FR-4 substrate with a relative permittivity of 4.2. Its dimensions are $15.5{\times}7.6{\times}0.4 mm^3$. The measured impedance bandwidths (VSWR<2) are 240 and 250 MHz at the operating frequencies, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.3
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• pp.409-426
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• 2001

Absorbed power of the human head radiated from a 900 MHz portable phone and temperature rise are computed using FDTD(Finite-Difference Time-Domain) method. For this computation the 5 layered media for the human head modeling and the monopole antenna attached to metallic box for the portable phone are used. To reflect the real circumstances typical sizes of human heads and portable phones are considered in the calculation. The length of monopole antenna is 8.15 cm, and the output power of a phone is 600 mW. Under the predetermined model the distribution of 1 g, 10 g averaged SAR and temperature rise rate over the human head are calculated, from which it was found that the position of maximum SAR is near at the head skin surface, not deep places far into the head. The position of the highest temperature is located far from the head skin more than that of the maximum SAR occured. The averaged SAR and temperature along the distance between the head and phone are calculated according to seperation distance between the head and phone.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2070-2072
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• 2004

극 초단의 임펄스를 사용하여 지중 매설물을 탐색하기 위한 지반탐사 영상 레이더를 개발하였다. 개발된 지반 탐사 레이더는 Gaussian 임펄스, 임펄스 송수신을 위한 초 광대역 소형 모노폴 안테나, 수신 신호 저장을 위한 고속 A/D로 구성된다. 탐지 깊이와 시스템의 크기를 고려하여 임펄스 발생기 및 초광대역 안테나가 설계되었다. 지중 매설물의 영상화를 위해 여러 가지 이미지 기법이 사용되었다. 발표에서는 구현된 시스템의 시제품을 소개하고, 개발된 시제품을 사용하여 가상의 모래 시험장에서 측정된 결과를 보일 것이다.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2022-2024
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• 2004

본 논문에서는 초광대역 기술을 이용한 고정밀 위치 추적용 센서를 위한 소형, 저가의 안테나를 제안한다. 안테나는 Fat monopole 과 유사하지만, Fat monopole의 상대적인 협대역 특성을 개선하기 위해 탭을 부가하여 고주파에서의 특성을 향상시켰다. 또한 급전은 제작이 용이한 Coplanar 도파관 구조를 사용하였다. 검증을 위해 3.1GHz${\sim}$5.1GHz 대역에서의 고 정밀 위치 추적용 센서를 위한 안테나를 설계하였다. 상용 EM 프로그램을 사용하여 안테나의 치수들에 대한 최적화 작업이 이루어 졌다. 실제 제작 결과와 시뮬레이션 결과가 비교되었고 상당히 일치함을 확인 할 수 있었다. 제작된 안테나는 2.5GHz${\sim}$7GHz대역내에서 10dB이상의 Return loss를 가졌다.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.3
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• pp.149-152
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• 2012

In this paper, a wideband monopole antenna with ring loop by modified ground plane is presented. The proposed antenna consist of monopole antenna, ring loop by ground plane. This antenna is fed CPW-fed and wide slot antenna of a novel structure for broadband characteristics is proposed. To enhance the impedance bandwidth of the wide slot antenna, we proposed the wide slot structure with CPW-fed which is combined with four ${\lambda}/2$ rectangular radiation modified monopole and inductively coupled. The measured impedance bandwidth is about 2.5 GHz(3.65~6.15 GHz) then less -10 dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.193-197
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• 2006

Radiation properties of flush mounted circular patch antennas are investigated. The patch is fed axis-symmetrically by a coaxial cable. Rigorous analysis iscarried out using integral transform and mode matching techniques. The presented method can accommodate a radiating patch, integrated matching section and band pass filter.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.307-312
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• 2005

In this paper, the broadband FCMA(Folded Cross Monopole Antenna), which is the cross monopole antenna with the folded element, is presented. To investigate the broadband characteristics of FCMA the VSWR, the gain, and the radiation pattern are calculated in frequency between 1.75 GHz and 2.655 GHz. From the calculated result, it is shown that the presented folded cross monopole antenna has a excellent band characteristics than the existing cross monopole antenna. The presented antenna is conformed as a broadband antenna which can be used for the indoor antenna of PCS, WCDMA, Wibro, and satellite DMB band.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1638-1639
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• 2011

본 논문에서는 초소형 무선 USB 동글 장치를 위한 광대역 접힌(folded) 모노폴 안테나를 제안하였다. 제안된 안테나는 CPW 급전으로부터 삼지창 형상의 선로를 적용하여 광대역 특성을 구현하였다. 최종 설계된 안테나의 크기는 $16{\times}44.8{\times}3.5\;mm^3$이며, low-profile의 무선 USB 동글용 안테나에 적합하다. 제안된 안테나는 $S_{11}$ < -10 dB 기준으로 2.28~10.8 GHz의 공진 주파수 대역을 가지므로 WiBro (2.3~2.4 GHz), Bluetooth (2.4~2.484 GHz), WiMAX (2.5~2.7 GHz, 3.4~3.6 GHz), satellite DMB (2.605~2.655 GHz), 802.11b/g/a WLAN (2.4~2.485 GHz, 5.15~5.825 GHz), UWB(3.1~10.6 GHz)의 무선 대역을 지원 할 수 있다. 측정된 평균 이득의 범위는 -3.41 dBi 에서 -0.84 dBi 이다.