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New Harmonic Suppressed Microstirp Ring Bandpass Filters

  • Park, Hyun-Joo;Kim, Jae-Hyuk;Park, Ji-Yong;Lee, Jong-Chu;Kim, Jong-Heon;Lee, Byung-Je;Kim, Nam-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.5
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    • pp.697-706
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    • 2000

  • In this paper, new bandpass filters that are composed of microstrip ring resonators with the center frequency of 5.775 GHz and the bandwidth of 100 MHz are presented. For the suppression of the unnecessary harmonics, lowpass filters are inserted into the feedlines and ring resonator itself, respectively These bandpass filters show good microwave characteristics with the harmonic suppression ratio of about 39 dB and 35 dB, respectively. Also, the varactor-tuned microstip ring bandpass filter with harmonic suppression is suggested and the tuning bandwidth of more than 450 MHz is obtained.

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Influence of gas mixture ratio on the secondary electron emission coefficient (${\gamma}$) of MgO single crystals and MgO protective layer in surface discharge AC-PDPs

  • Lim, J.Y.;Jung, J.M.;Kim, Y.G.;Ahn, J.C.;Cho, T.S.;Cho, D.S.;Kim, J.G.;Kim, T.Y.;Kim, S.S.;Jung, M.W.;Choi, S.H.;Ko, J.J.;Kim, D.I.;Lee, C.W.;Seo, Y.;Cho, G.S.;Kang, S.O.;Choi, E.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.117-118
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    • 2000

  • The secondary electron emission coefficient ${\gamma}$ of MgO single crystals according to the gas mixture ratio of Xe to Ne have been investigated by ${\gamma}-focused$ ion beam system. It is found that the MgO single crystals of (111) crystallinity has the highest ${\gamma}$ from 0.09(0.03) up to 0.16(0.04), while from 0.07(0.02) to 0.15(0.03) for (200) and from 0.06(0.01) to 0.13(0.02) for (220) crystallinity for operating Ne (Xe) ions ranging from 50eV to 200eV throughout this experiment. And it is found that the ${\gamma}$ ranged from 0.03 up to 0.06 for Ne-Xe mixtures are much smaller than those of 0.09 up to 0.16 for pure Ne ions under accelerating voltage ranged from 50V to 200V.

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