• 디지털산업정보학회논문지
• /
• 제10권2호
• /
• pp.21-27
• /
• 2014

In this paper, a planar sleeve monopole antenna for indoor digital TV reception is presented. The antenna has broadband property with the planar monopole and ground of sleeve. Sleeve monopole and ground conductors of the antenna are on the same plane, and exited through CPW feeding. Sleeve monopole and ground of proposed antenna exist on coplanar plane, and excite as CPW. It used FR4 epoxy dielectric substrate of ${\varepsilon}r=4.4$, and the size is $20[mm]{\times}170[mm]{\times}1.6[mm]$ dimension. So the internal antenna is suitable. The measurement results of the fabricated antenna, return loss is larger than -10 [dB] in 470~806 [MHz]. Maximum gain is 0.59 [dBi] on E-plane at 810 MHz and 1.70 [dBi] on H-plane at 640 [MHz]. Radiation pattern is about the same that of dipole antenna at all frequency.

• 한국전기전자재료학회논문지
• /
• 제25권9호
• /
• pp.727-731
• /
• 2012

This paper dealt with the measurement and analysis of electromagnetic waves radiated from a partial discharge (PD) source in insulation oil to apply condition monitoring of oil-immersed transformers. Two types of narrow-band monopole antennas with the resonant frequency of a 500 MHz and a 1 GHz were designed and fabricated. Also, a needle-plane electrode system was manufactured to simulate PDs and the curvature radius of the needle is 10 ${\mu}m$ and the diameter of the plane is 60 mm. Electromagnetic wave was measured by the PD measurement system with the monopole antennas. Detection sensitivity of the fabricated antenna was compared for the same PD magnitude; 620 $mV_{peak}$ for the 500 MHz antenna and 960 $mV_{peak}$ for the 1 GHz antenna to the PD magnitude of 74 pC. Consequently, the 1 GHz monopole antenna is more effective to detect PDs in oil-immersed transformers.

• 전기학회논문지P
• /
• 제65권1호
• /
• pp.72-75
• /
• 2016

In this paper, we proposes a internal antenna for wireless DVI dongle device using the folded monopole structure. The proposed antenna uses a basic structure of spiral and monopole. The antenna optimized for parameters length, gap, width, and rectangle of folded monopole antenna using the spiral structure. To confirm the characteristics of the antenna parameters, HFSS from ANSYS Inc. was used for the analysis. We used an FR4 dielectric substrate with a dielectric constant of 4.4. The DVI dongle size of the proposed antenna is $50{\times}40{\times}1.6mm$, and the size of the antenna area is $10{\times}40mm$. There is a value of return loss less then -10dB in 2.4GHz and 5.8GHz, band and the maximum antenna gain is -4.13dBi. The utilization possibility of the wireless DVI Dongle antenna have a folded monopole with spiral shape could be confirmed according to compare and analyze the simulation and measurement data.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
• /
• pp.300-304
• /
• 2002

We fabricated thick film monopole antennas using Mo-doped $BiNbO_{4}$ ceramics and investigated their electrical properties as a function of the Mo-doping concentration. Compared with undoped $BiNbO_{4}$ ceramics, 10 at.% Mo-doping improved microwave dielectric properties of ceramics by increased sintered density as well as decreased space charge density. Further increase in the Mo-doping concentration caused formation of $Bi_{2}MoO_{6}$ phases, resulting in deterioration of the microwave characteristics. The gain and bandwidth of the ceramic monopole antenna were also greatly affected by the Mo-doping concentration. When Mo-doping concentration was 10 at%, highest gain of ~0.7dBi with lowest bandwidth of 30% at 2.3GHz was obtained.

• 디지털산업정보학회논문지
• /
• 제9권4호
• /
• pp.43-49
• /
• 2013

In this paper, it is designed inverted triangle structural planar monopole antenna with edge and rectangle slot for UWB(Ultra Wide Band) communication (3.1~10.6 GHz) and researched in about 5.8 GHz notch structure to prevent interference between UWB systems and existing wireless systems for using Wi-Fi service. The antenna have broadband property structurally through inverted triangle structural planar monopole which have edge. and rectangle form addition planned notch slot of 1 mm and height 0.1 mm. Monopole and ground of proposed antenna exist on coplanar plane, and excite as CPW. It used FR4 epoxy dielectric substrate of ${\varepsilon}r$=4.4, and the size is $20{\times}20{\times}1.6$ mm dimension. The measured results that are obtained return loss under -10 dB through 3.1~10.6 GHz(7.5 GHz) without Wi-Fi bandwidth and maximum gain of 8.44 dBi at E-plane. Radiation pattern is about the same that of dipole antenna at all frequency. And using notch slot and it will be able to confirm the quality which becomes notch from 5.8 GHz which are a radio LAN frequency range.

• 한국자동차공학회논문집
• /
• 제16권1호
• /
• pp.45-51
• /
• 2008

This paper presents theoretical and experimental analysis on the characteristics of the power spectrum of electormagnetic waves radiating from the spark plug and their cables of a distributorless ignition system. The theoretical study was conducted applying the microwave transmission line theory and the antenna theory. The experimental works were carried out to measure the standing wave ratio(SWR) and the radiation power spectrum of this system. As a result, it has been found that a spark plug and its cable is working as a monopole antenna radiating elelctromagnetic waves. Because of its similar structure to a monopole antenna, the envelope of radiation power spectrum distribution has a bell shape which can be obtained from a monopole antenna operating as a series resonant circuit. The frequency characteristics from the SWR measurements show a similar frequency characteristics of power spectrum of the system studied. Also, it has been found that the density of the power spectrum of the system fitting a long time used spark plug is higher than that of fitting a new spark plug.

• 한국전자파학회논문지
• /
• 제25권1호
• /
• pp.114-122
• /
• 2014

RF 및 마이크로파 대역에서 동축 프로브 급전구조에 대한 효율적인 유한 차분 시간 영역(FDTD: Finite-Difference Time-Domain) 해석을 위한 등가 전원 모델링 기법들의 상호 관계를 연구하였다. 기존에는 델타 갭(delta-gap) 또는 자기 프릴(magnetic-frill) 개념을 FDTD에 도입한 등가 전원 모델들이 여러 연구진에 의해서 개발되었다. 이러한 등가 전원 모델들의 FDTD 구현 방법과 모의 계산의 정확성은 서로 조금 다르다는 정도로만 잘 알려져 있었다. 본 논문에서는 준정적 근사(quasi-static approximation)하에서 동축-프로브 급전 구조에 대한 FDTD 등가 전원 모델들의 상호 관계를 제시하였다. FDTD 등가 전원 모델들의 적용방법에 따라 동축 급전된 원추형 모노폴 안테나의 시간영역과 주파수영역 응답을 수치계산하였다. 또한, FDTD 모의계산의 정확성과 효율성에 대한 비교 결과를 제시하였다.

• 한국전자파학회논문지
• /
• 제17권4호
• /
• pp.335-340
• /
• 2006

본 논문에서는 국내 PCS 대역인 1,762.5 MHz의 세포실험용 전자파 노출 장치를 설계 및 제작하였다. 노출 장치는 도파관의 ${\lambda}_g/4$ 지점에 위치한 ${\lambda}_g/8$ 모노폴 안테나에 의해 $TE_{102}$ 모드로 동작되며, 노출 장치 내부에 내부 직경이 8.5 cm인 petri dish 1개를 노출시킬 수 있다. 세포실험용 전자파 노출 장치는 구형 공진기형으로 수치 해석 기법 중 하나인 FDTD 방법을 사용하여 SAR을 해석하였고 온도 프로브(model 790, Luxtron Corp)를 이용해 측정하였다.