• Journal of electromagnetic engineering and science
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• 제15권4호
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• pp.206-212
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• 2015

This paper introduces new wideband antenna-filter-antenna (AFA) uniform arrays that can be utilized as frequency selective surfaces (FSS) with low loss and sharp roll-off response, which are highly desirable characteristics for millimeter wave applications. The design adopts a simple 3-layer single polarization structure consisting of two patch antennas and a resonator. Both simulations and measurements are used to characterize the performances of the proposed design. Overall results show 18.5% 10-dB bandwidth. For the targeted band the insertion loss is less than 0.2 dB. Possible applications include quasi-optical amps, grid mixers and radomes for aircraft radar antennas.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 춘계종합학술대회
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• pp.39-42
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• 1999

어댑티브 어레이 안테나를 이동체에 적용하는 경우 가중계수벡터를 전파 환경의 변화에 고속 적응시킬 필요가 생긴다. 4소자 등간격 선형 어레이 안테나 시스템에 대하여 일정 진폭의 포락선을 갖는 BPSK와 FSK신호에 LMS와 Kalman filter 알고리즘을 적용한 컴퓨터 시뮬레이션 결과 LMS에 비하여 Kalman filter 알고리즘이 수렴성이 빠르고 신호의 추종성이 매우 뛰어남을 확인 할 수 있었다.

• Journal of electromagnetic engineering and science
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• 제16권2호
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• pp.100-105
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• 2016

We have designed a three-channel output multiplexer (OMUX) using a band-pass filter and an ultra-wideband (UWB) antenna. The proposed band-pass filter is composed of an inner rectangular loop, an outer open stub, and a defected ground structure. The outer open stub can be used to control the pass band, and the inner rectangular loop can improve the insertion loss characteristics of the band-pass filter. The proposed band-pass filter, UWB antenna, and OMUX are fabricated and measured. The designed OMUX can cover the band group 1 (3,168-4,752 MHz) of WiX system. The measured radiation patterns are close to those of a conventional dipole antenna and the measured antenna gain varies from 1.8 dBi to 3 dBi over the operating frequency range.

• 한국항행학회논문지
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• 제14권1호
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• pp.11-19
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• 2010

본 논문에서는 밀리미터파대역에서 동작하는 H면 여파기 결합 안테나를 제안하였다. 여파기 결합 안테나는 여파기가 안테나에 삽입된 형태이며 안테나의 반사손실을 줄이고 지향성을 높이기 위하여 다층의 유전체 렌즈가 결합되었다. 도파관 형태의 여파기와 안테나는 가상의 도체벽을 형성하는 via의 배열을 PCB기판에 구현함으로서 크기의 감소를 꾀하였으며 안테나와 여파기를 일반적인 도파관에서 설계한 후 PCB 기판에 축소하여 구현한 후 결합을 시도하였다. 유전체 렌즈의 두께를 조절하기위해 단층 및 다층의 유전체 기판을 사용하였으며 그 결과로 41.5 GHz의 중심주파수에서 8, 13.5 dBi의 시뮬레이션 이득을 각각 얻을 수 있었다.

• 대한전자공학회논문지
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• 제11권4호
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• pp.9-16
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• 1974

The low channels with frequency range of 54~88MHz and the high channels with frequency range if 174~216 MHz are in use for TV broadcasting in Korea. Since the ratio of the highest frequency to the lowest frequency is 4 to 1, only a logarithmic periodic antenna cou1d cover such an wide frequency range. But, this log-periodic antenna should be big in size. Studies have been done on an antenna of small size with reasonable gain which combines through a channel filter a LPD antenna if low channel with boom length of 2m and a LPD antenna of high channel with boom length of 1.8m. The whole antenna is connected to feeder line through a talun. Experiment shows that the gain of low and high channels is 7 dB and 9 dB respectively, which are lower than theoretical values br nomore than ldB. The difference seemed to come from slight impedance mismatches between antennas and feeder lines, loss in the filter and measurement errors.

• 한국전자통신학회논문지
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• 제11권11호
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• pp.1039-1046
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• 2016

논문에서는 야생동물의 생활 패턴과 습성을 연구하기 위해 Yagi-Antenna, Low Pass Filter, Angle 추적기술 등을 이용한 야생동물 위치추적 시스템을 연구하였다. 현재 일반적으로 VHF 라디오식 위치측위 기술을 사용하여 야생동물 위치추적 시스템에 사용되고 있다. 기존 Yagi-Antenna는 이동성을 고려하여 4-element가 사용되며, 휴대성에 대한 장점이 있지만 이득이 낮고 지향성이 약하다. 제안된 기술은 이득을 높이기 위해 6-element를 채택하여 Narrow Space Yagi-Antenna 기술을 구현 하였다. 또한 수신 신호의 정밀한 방향 검출 기술과 3대의 수신기를 이용한 AOA(:Angle Of Arrival) 위치측위 기술을 적용하였다. 이를 바탕으로 본 연구에서는 공간적으로 특정한 서식영역에서 활동하는 야생동물 생활패턴과 습성을 파악하기 위한 위치추적 기술을 개발하여 검증 하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.101-104
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• 1996

A new detecting system for moving objects of coastal region has been designed by directional antenna and driving circuits. The designed system has been investigated by CAD for linear and planar antenna arrays of various radiating elements for antenna simulations and by P-spice of device simulations. For detecting the displacement of moving objects, we constructed four wideband dipole antenna, diode switching circuit, mixer, filter and amplifier. The results of antenna receiver were shown a possibility of distance measuring system through phase difference of radiation patterns in antenna simulation

• 한국ITS학회:학술대회논문집
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• 한국ITS학회 2004년도 제3회 정기총회 및 추계학술대회
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• pp.81-84
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• 2004

• 전기학회논문지
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• 제56권4호
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• pp.768-772
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• 2007

Integration of RF front end module(FEM) into the antenna has been investigated in USPCS band (1.88GHz-1.99GHz). The FEM consists of input filter, power amplifier, coupler, power detector, bias switch and duplexer. The antenna was designed in planar inverted F antenna(PIFA) structure to implement it inside the handset. In order to avoid strong coupling between the antenna and FEM, a shielding ground layer was placed between them. The antenna size is 19mm by 10mm by 6mm under which FEM whose size is 8mm by 5mm by 1.5m locates. The antenna impedance was selected to match to FEM having better efficiency rather than gain since FEM has enough gain whose system spec is minimum of 20dB. The antenna patterns are shown with and without FEM.

• Journal of electromagnetic engineering and science
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• 제16권1호
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• pp.35-43
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• 2016

A compact ultra-wide band antenna with a quadruple band-notched characteristic is proposed. The proposed antenna consists of a slotted trapezoid patch radiator, an inverted U-shaped band stop filter, a pair of C-shaped band stop filters, and a rectangular ground plane. To realize the quadruple notch-band characteristic, a U-shaped slot, a complementary split ring resonator, an inverted U-shaped band stop filter, and two C-shaped band stop filters are utilized in this antenna. The antenna satisfies the -10 dB reflection coefficient bandwidth requirement in the frequency band of 2.88-12.67 GHz, with a band-rejection characteristic in the WiMAX (3.43-3.85 GHz), WLAN (5.26-6.01 GHz), X-band satellite communication (7.05-7.68 GHz), and ITU 8 GHz (8.08-8.87 GHz) signal bands. In addition, the proposed antenna has a compact volume of $30mm{\times}33.5mm{\times}0.8mm$ while maintaining omnidirectional patterns in the H-plane. The experimental and simulated results of the proposed antenna are shown to be in good agreement.