• Title/Summary/Keyword: Filter band

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LONG-SLIT SPECTROSCOPY FOR EXTENDED OBJECTS (면천체(EXTENDED OBJECTS)에 대한 긴 슬릿 분광관측 연구)

  • SUNG EON-CHANG
    • Publications of The Korean Astronomical Society
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    • v.15 no.spc1
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    • pp.39-60
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    • 2000
  • We will discuss two-dimmensional spectrophotometry including long-slit spectroscopy and narrow-band imaging. The basic principles, applications, and techniques of observations and data reduction of spectroscopy and spectrophotometry for extended objects are described. This discussion will focus on practical long-slit spectroscopy using a Cassegrain spectrograph attached with 2 or 4m class telescopes and on imaging spectrophotometry using narrow-band interference filter sets. We will discuss scientific applications.

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Novel Dual-Mode Microstrip BandPass Filters with Enhanced Coupling Structures (향상된 커플링 구조를 이용한 새로운 이중모드 마이크로스트립 대역통과 필터)

  • 정회성;강은균;이윤주;임춘섭;권성수
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.71-74
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    • 2000
  • 본 논문에서는 무선LAN용으로 사용할 수 있는 마이크로 스트립을 이용한 대역동과 필터를 설계하였다. 기존의 링이나 square loop의 구조를 이용한 공진기와는 다르게 cross loop 와 meander loop의 구조를 이용한 공진기를 혼합한 형태로써 크기가 상당히 줄어든 새로운 구조와 BandPass Filter를 설계하였다.

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Photonic Band Gap Characteristics by Shape of Lattice with Uniformity Area (동일한 면적을 가지는 격자의 모양에 따른 광자 밴드갭 특성에 관한 연구)

  • 김기욱;오범환;이승걸;박세근;이일항
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.07a
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    • pp.226-227
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    • 2003
  • 광자 크리스탈 (Photonic Crystals)은 서로 다른 유전체의 주기적인 구조로 이루어져 있으며, 전자기파가 특정한 주파수 범위에서 전파하지 못하고 차단되는 영역인 광자 밴드갭 (Photonic Band Gap)이 존재한다. 이러한 광자 밴드갭의 존재로 인하여 빛의 흐름을 조절할 수 있다는 점 때문에 반사거울, 휘어진 도파로(bent waveguide), 레이저, 채널 드롭핑 필터(channel dropping filter) 등 여러 가지 다양한 분야에 응용될 수 있다. (중략)

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2.5 GHZ SECOND-AND FOURTH-ORDER INDUCTORLESS RF BANDPASS FILTERS

  • Thanachayanont, Apinunt
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.86-89
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    • 2002
  • A new design approach for realising low-power low-voltage high-Q high-order RE bandpass filter is proposed. Based on the gyrator-C inductor topology, a 2$\^$nd/-order biquadratic bandpass filter can be realised by adding a series capacitor to the input port of the gyrator. High-Q 2$\^$nd/-order and 4$\^$th/-order fully differential RF bandpass filters operating in the 2.4-㎓ ISM (Industrial, scientific and medical) frequency band under a 2-V single power supply voltage with low power dissipation are reported.

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SAW MSK Matched Filler for Spread Spectrum Communications (스펙트럼 확산 통신용 SAW MSK 정합필터)

  • Park, E.C.;Park, Y.S.;Whang, K.C.
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.837-840
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    • 1987
  • In this paper, an MSK modulator and MSK matched Filter using SAW component which is small size and can process high Frequency and wide band signals are described. This modulator and matched Filter have been shown applicable to the transmitter and receiver of spread spectrum communication systems.

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New Fully-Differential CMOS Second-Generation Current Conveyer

  • Mahmoud, Soliman A.
    • ETRI Journal
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    • v.28 no.4
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    • pp.495-501
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    • 2006
  • This paper presents a new CMOS fully-differential second-generation current conveyor (FDCCII). The proposed FDCCII is based on a fully-differential difference transconductor as an input stage and two class AB output stages. Besides the proposed FDCCII circuit operating at a supply voltage of ${\pm}1.5\;V$, it has a total standby current of $380\;{\mu}A$. The applications of the FDCCII to realize a variable gain amplifier, fully-differential integrator, and fully-differential second-order bandpass filter are given. The proposed FDCII and its applications are simulated using CMOS $0.35\;{\mu}m$ technology.

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A design of a multi-layer filter/duplexer using stepped impedance resonator (SIR 공진기를 이용한 적층형 필터/듀플렉서 설계)

  • 이종훈;김영태;강병권;정명섭;박준석;임재봉
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2002.11a
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    • pp.169-172
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    • 2002
  • In this paper, the design formulas for bandpass filters using parallel coupled stepped impedance resonators(SIR) are derived. General content about basic feature of stepped impedance resonators(SIR) is represented. The filters and duplexer using stepped impedance resonators(SIR) have been designed and realized with the presented design method at IMT-2000 frequency band Simulations have used serenade circuit simulation and HFSS EM-simulation. We were showed excellent agreements between SIR design theory and simulation results on the multi-layer filter/duplexer.

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Design of digital filters using linear programming (선형 프로그래밍에 의한 디지탈 필터의 설계)

  • 조성현;임화영
    • 제어로봇시스템학회:학술대회논문집
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    • 1986.10a
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    • pp.137-141
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    • 1986
  • This paper presents optimal recursive digital filter design to meet simultaneous specifications of magnitude and linear phase characteristics. As is well known, the overshoot in the vicinity of discontinuity is hight. The technique using linear programming (the dual programming) is choosing more specification points in the vicinity of band limit frequency. The resulting filter can shown improved response and numerical accuracy with reduced nonuniform specification points in frequency domain.

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A study on Photolithography of band pass filter for communication devices (통신기기용 대역통과필터의 공정에 관한 연구)

  • Lee, Dong-Yoon;Shin, Yong-Deok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05c
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    • pp.247-250
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    • 2002
  • SAW filters were fabricated on $LiNbO_3$ substrates to evaluate frequency response and properties of photolithography. In the both of etch and lift-off methods, lift off method was superior to etch method in fabrication process. Frequency response property was measured by network analyzer. From measurement of acoustic property, SAW propagation velocity was 3574.9m/sec for $LiNbO_3$ SAW filter.

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