• ETRI Journal
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• 제31권5호
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• pp.506-509
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• 2009

A novel design of a compact square-ring slot microstrip antenna for achieving circular polarization (CP) operation is proposed and experimentally studied. By using an arrow-shaped slot structure as a radiating element, the resonant frequency of the proposed antenna is significantly lowered, which can lead to a large size reduction for fixed frequency operation. The CP radiation characteristics are achieved by loading with proper asymmetry, which can be placed diagonally. A prototype of the proposed design is implemented and its performance is measured. Measured results show that radiation patterns with good CP characteristics are obtained at the resonant frequency.

• Journal of electromagnetic engineering and science
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• 제9권4호
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• pp.223-228
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• 2009

In this paper, a quadrafilar antenna is designed to have a lower profile as an essential part of the size reduction technique and lower back radiation(i.e. higher forward radiation) for the S-band telemetry/telecommand(TM/TC) function of a communication satellite. Particularly, to meet the challenging requirements on the higher isolation between the TM/TC antennas and simultaneously a smaller size, the lowest back radiation and lowest cross-polarization, the optimal physical dimensions of the quadrafilar antenna are found by using the Genetic Algorithm(GA). To prove the validity of the proposed antenna design, its 3D electromagnetic analysis and measured results are compared, showing good agreement.

• 한국IT서비스학회지
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• 제12권3호
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• pp.323-330
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• 2013

In this paper, miniaturized patch antenna operating at ISM band has been designed by applying the fractal technique. Various type of antenna structure, microstrip patch antenna and koch curve microstrip patch antenna has been proposed and simulated using Ansoft HFSS (High Frequency Structure Simulator). The area of microstrip patch antenna and koch microstrip patch antenna is 1,058 $mm^2$, and 891 $mm^2$ respectively, showing the size reduction ratio of 16%. The finally made koch curve microstrip patch antenna resonates at 2.45GHz with return loss of 22.69dB, VSWR of 1.2142, and antenna radiation gain of 3.26dBi.

• 한국ITS학회 논문지
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• 제8권4호
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• pp.39-45
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• 2009

본 논문은 기생면을 이용한 마이크로 스트립안테나 형태로 소형화 된 방사체와 증폭단를 결합하여 AM/FM 대역, DMB 대역 및 GPS 대역을 수신할 수 있는 차량용 통합 안테나를 설계 및 제작 하였다. 제작한 능동형 안테나는 AM/FM 대역에서 기존의 평면형 안테나에 비해 15% 이상의 크기 축소 효과를 나타내었다. 또한 상용 헬리컬 안테나와 동등한 수신 성능 특성을 나타내었며 DMB 및 GPS 대역에서도 만족할만한 수신 성능 특성을 나타내었다. 제작된 능동형 안테나의 크기는 $133{\times}31{\times}1.2mm$이고, 단일 입력 단자와 2개의 출력 단자를 갖는다.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.397-400
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• 2005

본 논문에서는, PIFA 끝 부분을 접은 DMB 차량용 폴디드 PIFA를 제안한다. PIFA의 단락스트립 반대편 끝 부분을 접음으로써 1/4 파장이 아닌 1/10 파장에서 공진 주파수가 형성된다. 이는 PIFA에 비해 60 % 정도의 안테나 크기 축소 효과를 가진다. 또한 기생패치를 사용했을 때 폴디드 PIFA는 대역폭이 늘어난다. 따라서 제안된 안테나는 차량용 지상파 Digital Multimedia Broadcasting (DMB) 안테나로 응용이 가능하다.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1777-1782
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• 2016

A compact and broadband balun is designed using a conventional right-handed transmission line (RHTL) and a left-handed transmission line (LHTL) with lumped elements only. The proposed balun maintains a phase difference of $180^{\circ}{\pm}12^{\circ}$ at the output ports for the frequency range of 1.27 GHz-2.69 GHz. Nevertheless, the circuit size is merely $9.5mm{\times}12.7mm$. To verify the performance of the proposed balun, we attached it to a dipole-type antenna and observed that the return loss is greater than 10 dB for the frequency range between 1.86 GHz and GHz. The radiation pattern and peak gain are similar to those of the dipole antenna with a conventional balun.

• 반도체디스플레이기술학회지
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• 제21권3호
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• pp.125-129
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• 2022

The current display technology tends to be highly integrated with high resolution, the element size is gradually downsized, and the structure becomes complicated. Inductively coupled plasma (ICP) dry etcher of various types of etching equipment is a structure that places a large multi-divisional antenna source on the top lid, passes current to the Antenna, and generates plasma using the induced magnetic field generated at this time. However, in the case of a device of a large area size, a support that can withstand a load structurally is necessary, and when these support portions are applied, arrangement of antenna becomes difficult, which causes reduction in uniformity. As described above, the development of antenna source of a large area having a uniform plasma density on the whole surface is difficult to restrict hardware (H/W). As a solution to this problem, we confirmed the change in uniformity of plasma by applying two kinds of specific shape faraday shield(FICP) to the lower part of the large area upper lid antenna of 6 and 8th more than that generation size. In this thesis, we verify the faraday shield effect which can improve plasma uniformity control of ICP dry etcher equipment applied to medium and large displays.

• 전자공학회논문지A
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• 제33A권6호
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• pp.99-107
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• 1996

When GPS (global positioning system) is used as synchronous signal in CDMA digital cellular base station system and high speed digital synchronous communication network, antenna cable length is increased, comparing with other GPS application such as positioning or car navigation. In this paper, it is proposed that a type of new GPS antenna system including RF stage for reduction of cable loss in case of long cable.The antenna system with TMPA(truncated-corners microstrip patch antenna) is designed and fabricated because GPS signal has RHCP (right-hand circular polarization), consequently antenna size can be made small size. LNA (low noise amplifier) is designed by using HEMT(high electron mobility transistor)which has lower noise figurae and better AGC characteristics at low voltage than GaAs FET, and we equiped mixer, in GPS antenna unit, which converts from 1575.42MHz to 75.42MHz. As result of comparing between typical system and proposed system when cable length is 60m, 63dB, 55dB and 25dB gain are obtained for RG-316/U, RG-58C/U and RG-213/U, and better characteristics are achieved than typical system as far as cable length is longer.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.564-566
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• 2012

본 논문에서는 코프래너 도파관으로 급전되는 소형 광대역 평면 모노폴 안테나의 설계방법에 대해 연구하였다. 제안된 구조의 광대역 모노폴을 지상파 디지털방송 수신용으로 최적화 설계하였다. 광대역 모노폴은 특성 임피던스 75옴의 코프래너 도파관으로 급전되고 $100mm{\times}200mm$ 크기의 FR4 기판에 설계하였다. 모노폴을 소형화 하기 위해 슬릿을 부가하고 급전선과 모노폴의 임피던스 정합을 위해 유도성 스터브를 장하하였다. 디지털 방송 주파수 대역인 470-806 MHz 대역에서 동작하도록 설계된 안테나를 FR4 기판 상에 제작 후 실험을 통하여 연구결과의 타당성을 검증하였다.

• Journal of electromagnetic engineering and science
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• 제7권2호
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• pp.96-101
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• 2007

A design of circular polarized(CP) microstrip antenna with a fenced ground is proposed and the equivalent circuit is derived. The antenna consists of a square radiating patch with a pair of truncated comers, a bottom ground and a fenced ground. From conducted experiments, a patch size reduction using the metal fence as large as 25% from the conventional patch structure, has been obtained. The input admittance of the extracted equivalent circuit is shown to agree with that of the measurement. And the design parameters and performance of the proposed antenna are examined by analyzing the fields and circuit behaviors.