• Title/Summary/Keyword: dielectric-rod

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The Microwave Measurement of the Dielectric Properties of Low-Loss Materials by the Dielectric Rod Resonator Method (마이크로파에서 Dielectric rod resonator method에 의한 저유전 손실 물질의 유전 특성 측정에 관한 연구)

  • 심화섭;이한영;김근영;김진헌
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1989.06a
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    • pp.21-25
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    • 1989
  • Theory and experimental results are presented to show the possibility of using a dielectric rod resonator method for characterizing dielectric materials at microwave frequency. The measuring structure is a resonator made up of a cylindrical dielectric rod placed between two parallel conducting plates. In this system, the TE$\_$011/ mode frequency was adapted to minimize the effect of the air-gap between the rod and the conducting plates. The dielectric properties are computed from the resonance frequencies, structure dimensions and 3-dB bandwidth.

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The Microwave Measurement of the Dielectric Properties of Low-Loss Materials by the Dielectric Rod Resonator Method (고주파 대역에서 Dielectric Rod Resonator 방법에 의한 저유전 손실 물질의 유전 특성 측정)

  • Kim, Geun-Young;Shim, Hwa-Sup;An, Chul;Chang, Ik-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.10
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    • pp.10-15
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    • 1990
  • Theory and experimental results of measuring the microwave dielectric characteristics of low-loss materials by using dielectric rod resonator method are presented. The $TE_{011}$ mode resonance frequency was adapted to minimize the effect of the air gap between the rod and the conducting plates. The dielectric properties were computed from the resonance frequency, sample geometry and 3 dB bandwidth. The error of measurements was within ${\pm}3{\%}$ for dielectric constant and was within ${\pm}12{\%}$ for dielectric loss.

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Leaky Dispersion Characteristics in Circular Dielectric Rod Using Davidenko's Method

  • Kim Ki Young;Tae Heung-Sik;Lee Jeong-Hae
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.72-79
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    • 2005
  • The leaky dispersion characteristics of a circular dielectric rod were investigated using Davidenko's method for several lower-order transverse magnetic(TM) modes. The normalized complex propagation constants were precisely determined and their tolerances below $10^{-10}$ compared with zero for both real and imaginary parts. It was also checked whether the normalized complex propagation constants obtained represented forward leaky waves. The leaky modes existing below the cutoff frequency of the guided mode were classified as a nonphysical mode, reactive mode, antenna mode, and spectral gap based on a precise determination of the complex propagation constants. Finally, the effects of the dielectric constant and radius of the dielectric rod on the leaky dispersion characteristics were also considered.

Analyzed of the Circular Dielectric Rod Antenna Having Sing1y Fed CP Microstrip Antenna (단일급전 마이크로스트립 안테나를 사용한 유전체 봉 안테나의 해석)

  • Chun, Young-Ho;Chung, Hawn-Yong;Chung, Dae-Sik;Ko, Ji-Hwan;Cho, Young-Ki
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2005.11a
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    • pp.367-370
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    • 2005
  • In this paper, we made a Singly Fed patch which is the fittest at the feeding part. And we found out return loss and radiation pattern about dielectric rod array antenna which has six's passive element to shape FTEP(Flat-topped element pattern) after we analyzed the characters of singly dielectric rod antenna. We show the conclusion that has the optimum return loss and more flat radiation pattern.

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EM WAVE PENETRATION INTO A CYLINDRICAL CAVITY WITH A CENTER DIELECTRIC-ROD (중심의 유전체 막대가 있는 원통형공동의 전자파흡수)

  • Cho, Chul;Rhee, Un-Dong
    • 전기의세계
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    • v.28 no.2
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    • pp.68-75
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    • 1979
  • The penetration of an electro-magnetic wave through an aperture in a cylindrical structure with a center dielectric-rod is investgated. By using a standard mode matching procedure, the electrical and magnetic fields in a cavity are determined as a function of position inside the cavity and frequency of the incident field. For the given parameters, computed data are obtained and the results exhibited in form of amplitude curves of the nor malized field and energy densities of functions of position and frequency. Depending on the increase of the relative dielectric constant of center dielectric-rod, the resonance frequecies of the cavity vary as the cavity size decrease. The stored electro-magnetic energy varies very rapidly as a function of position inside the cavity and of the source frequency. Its peak value can be two orders of magnitude greater than the incident energy density. The frequencies where the peaks occur can be identified approximately as the resonance frequencies of the cavity.

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A Resonant Mode Identification in Cylindrical Cavity Resonators with Concentric-rod using Non-decaying Mode Analysis (유전체 봉이 삽입된 원통형 공동 공진기에서의 non-decaying 모드 해석을 이용한 공진 모드 구분)

  • Lee, Won-Hui;Kim, Tai-Shin;Kang, Min-Woo;Koo, Kyung-Wan;Hur, Jung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.1069-1072
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    • 2001
  • We described a method resonant mode identification in dielectric-rod loaded cylindrical cavity resonators. Resonant frequency of dielectric loaded cavity is calculated by analyzing the characteristic equation. The characteristic equation is solved by using the ContourPlot graph of Mathematica. As the result of comparing calculation value and experimental value of resonant frequencies, we know that the field representation of non-decaying mode is exact. The contour graph method is not a method using approximated representation of electromagnetic field variation at the outer area of dielectric in the resonators but a method using exact representation.

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Analysis of Leaky Modes on Circular Dielectric Rods using Davidenkos Method

  • Kim, Ki-Young;Tae, Heung-Sik;Lee, Jeong-Hae
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.356-360
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    • 2002
  • Leaky modes on a circular dielectric rod are investigated from the precisely determined normalized complex propagation constants using Davidenko's complex root finding technique. Below the cutoff frequency of the guided mode, distinct frequency regions that have unique properties are observed, such as nonphysical region, antenna mode region, reactive mode region, and spectral gap region. The effects of tro design parameters, dielectric constants and the radius of the rod, to the leaky mode characteristics are also considered.

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A Study on the Phase Noise Improvement of Oscillator using Dielectric-rod loaded Cavity Resonators with HIS End-plates (고온초전도체와 유전체 삽입 공동 공진기를 이용한 발진기의 위상잡음 개선에 관한 연구)

  • Lee, Won-Hui
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.2
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    • pp.174-177
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    • 2009
  • In this paper, an oscillator using dielectric-rod loaded cavity resonators with HTS(High Temperature Superconductor) end-plates was presented. It was operated at X-band. A two port cavity resonator was incorporated into a basic feedback loop oscillator configuration. A rutile loaded cavity resonator with HTS thin film end-plates was used to provide the quality factor between $10^4$ and $10^6$. A parallel feedback oscillator was constructed with a dielectric loaded cavity resonator, an amplifier, and a directional coupler. At 300 K, the experimental results showed the phase noise of -108 dBc/Hz at a 100 kHz offset frequency. At 26 K, the results was -118.8 dBc/Hz at same offset frequency.

Design of Waveguide Dielectric Rod Antenna for Shaping, FTEP (Flat-topped Element Pattern) for HAPS

  • Kim Yang Su;Kang Byung Su;Ku Bon lun
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.880-882
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    • 2004
  • This paper presents the design and simulation results of 7 waveguide dielectric rod array antennas for 7 channel DBF(Digital beamformer) receivers for stratospheric system. A waveguide. dielectric antenna type, which has FTEP(Flat-toped element pattern) to manufacture easily. Also, the calculated element patterns according to the permittivity are compared. The designed antenna will be used for generating multibeam radiation pattern by means DBF.

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Dielectric Loaded Small Conical Horn Antennas for Portable LMDS Communication (LMDS 휴대통신용 유전체 장하 소형 원추형 혼 안테나)

  • 김재학;원충호;이태훈;이홍민
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.306-310
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    • 2002
  • 본 논문에서는 기존의 혼 안테나에 Dielectric rod를 삽입하는 구조를 사용하였다. 입력구조는 Rectangular Waveguide Feed에 Cone을 접목시키는 형태로 구현되었으며 기존의 E-Plane taper구조보다 특성이 양호하며 소형화를 구현해냈다. 제작된 안테나의 중심주파수는 37GHz이며 정재파비 특성 또한 양호하다. 여러 Feeding 구조 중 Bandwidth를 좀더 확장할 수 있는 구조에 초점을 맞추어 대역폭은 13%이상을 구현했으며 시뮬레이션 툴은 Ansoft HFSS V7.0으로 최적화한 후 제작 및 측정하였다. 또한 사용된 Dielectric rod의 제질은 Teflon(ETFE, $\varepsilon$$_{r}$=2.03)을 사용하였다.

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