• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.2
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• pp.505-513
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• 1996

In this paper the dual-mode bandpass filters with a Chebyshev response are designed and manufactured at Ku-band as well as K-band. Manufactured filters are resonated by two independent orthogonal $TE_{113}$ circular-cavity modes and characterized by 4-pole Chebyshev function. One is operating at a center frequency of 12.5GHz with a bandwidth of 100MHz and the other, a center frequency of 19.25GHz with 120MHz, respectively. The measureed experimental results of a 12.5GHZ dual-mode filter ahve a 1.2dB intertion loss in the passband and 65dB out-of-rejection, and a 19.25GHz filter has a 1.55dB insertion loss and 70dB out-of-rejection. These experimantal results shoults show good agreements with the design specifications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.4 s.95
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• pp.438-446
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• 2005

In this paper, the modified generalized Chebyshev rational function is presented. The new element values of prototype low pass filter are obtained by network synthesis using this rational function. This proposed filter has an equal ripple passband as same as conventional generalized Chebyshev filter, but unlike conventional filter which has only one attenuation pole at finite frequency, the proposed filter has two different from each other attenuation pole in stopband. If the harmonic frequency is set to the second attenuation pole frequency, this harmonic is suppressed efficiently. Furthermore, since the location of the second attenuation pole can be arbitrary adjusted. our filters are very available for the realization of wide stopband, particularly.

• Journal of IKEEE
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• v.15 no.1
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• pp.57-63
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• 2011

This paper presents a tunable band pass filter (BPF) for multi bio-signal detection. The bandwidth can be controlled by the bias current of transconductance (gm), while conventional BPF exploited switchable capacitor array for band selection. With this design technique, the die area of proposed BPF reduced to at least one tenth the area of conventional design. The simulation results show the high cut-off frequency tuning range of from 100Hz to 1Khz. The circuit was implemented with a 0.18um CMOS standard technology. Total current consumption is 1uA at the supply voltage of 1V with sub-threshold design technique.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.5 s.305
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• pp.43-50
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• 2005

This paper describes some IC(integrated circuits) design and implementation techniques of low power multi-band Gm-C bandpass filter for body composition analyzer. Proposed BPF(bandpass filter) can be selected from three bands(20 KHz, 50 KHz, 100 KHz) by control signal. To minimize die area, a simple center frequency tuning scheme is used. And to reduce power consumption, operational transconductance amplifier operated in the sub-threshold region is adopted. The proposed BPF is implemented with 0.35 um 2-poly 3-metal standard CMOS technology Chip area is $626.42um\;{\times}\;475.8um$ and power consumption is 700 nW@100 KHz.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.172-172
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• 2017

본 연구는 차량의 AW(AutoWiping) 기능을 위해 장착된 강우센서를 이용하여 강우정보를 생산하는 기술을 개발하고자 하였다. AW(AutoWiping) 기능이란 차량 앞창(Windshield)에 빗방울이 맺히게 되면 광신호의 산란으로 인해 수광부에 들어오는 감소되는 광신호의 정도에 따라 차량 와이퍼의 속도를 결정해 주는 기능이다. 빗방울이 많이 맺힐수록 광신호는 감소되며 와이퍼는 더 빠른 속도로 작동을 하게 된다. 여기서 강우센서가 강우량이 많으면 감소된 광신호 데이터를 표출하는 현상을 이용하여 강우정보를 생산한다. 강우센서는 총 8개의 채널로 이루어져있고, 초당 250개의 광신호 데이터를 수집하며, 10분이면 약 120만 개의 데이터가 생산되게 된다. 이 대량의 데이터에서 정확한 강우량을 산출하기 위해 강우센서의 초기값과 와이퍼 이동시 발생하는 순간 이상치를 제거해야 한다. 하지만 일일이 수백만 개 이상의 데이터에서 모든 이상치를 제거하는 작업은 불가능하다. 따라서 이상치를 포함한 회귀 분석 방법을 연구하였고, 인공강우 발생기를 이용하여 광신호를 강우량으로 환산하는 2가지 회귀식이 유도되었다. 이들은 각각 이상치를 모두 포함시켜 독립변수(광신호)에 따라 종속변수(강우량)의 값이 변화하는 관계를 나타내는 선형회귀분석(model 1), 임계치를 정하여 일정 이상치가 제거된 신호만 통과시키는 대역통과 필터링 분석(model 2)으로 유도된 회귀식을 실강우에 회귀식을 적용하여 정확도를 분석하였다.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.38-42
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• 2005

CMOS analog lowpass filters using speech signal bandwidth for a Asymmetrical Digital Subscriver Line(ADSL) modem are presented. Designed active lowpass filters are composed of the CMOS complementary high-swing cascode stage which can increase transconductance of an active element. As a result, their cutoff frequency are 138kHz and 1,100kHz respectively. A low-voltage high-swing cascode integrator which improved on a gain and unit gain frequency used to design the filters. The designed filters are verified by HSPICE simulation with the $0.251{\mu}m\;CMOS\;n-well$ Parameter and a single 2.5V power supply.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.2 no.4
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• pp.10-16
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• 1991

A microstrip bandpass filter using stepped impedance resonators and tapped input / output is realized with Teflon substrate, whose center frequency is 3.5 GHz and fractional bandwidth is 20%. In order to realize a wider bandwidth of 30%, the Crystal's design method and the input / output tapping scheme are used. Another microstrip filter designed as mentioned above is realized with Epsilam-10 substrate. This case shows good agreement between the theoretical responses and the measured ones.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.5
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• pp.369-375
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• 1996

This paper described the miniaturization of microstrip bandpss filter in UHF using S-plane Prototype. Modern microwave receiver system requires smaller size and better filter performance. The design of filters using bandpass S-plane prototype is made to satisfy these requirements. Bandpass S-plane prototypes are made by exact-synthesis technique using transmission zero locations at wanted frequency bandwidth, and the calculation of prototype values was performed by computer.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.2253_2254
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• 2009

무선 모바일 통신 시장의 성장에 따라 수동 소자로 구성된 모듈에 대한 관심이 높아지고 있다. 본 논문에서는 수동소자를 이용한 Wi-MAX용 트리플렉서를 설계하였다. 트리플렉서는 Wi-MAX의 RF Front-end단 앞부분에 연결되며, IEEE 802.16에 따른 2GHz, 3GHz, 5GHz 대역을 선택, 분리해주는 역할을 한다. 제안된 트리플렉서는 저역통과필터, 대역통과필터, 고역통과필터로 구성하였으며, 수동소자의 최소화로 인해 삽입손실 향상을 중점으로 설계하였다. 회로해석 결과, 각 대역별 (2/3/5GHz) 삽입손실은 각각 -0.5dB, -0.6dB, -0.4dB 였으며, 반사손실은 -20dB, -20dB, -12dB, 격리도는 -20dB, -24dB, -25dB의 특성을 보였다. 수동 소자의 최소화 설계로 인해 모듈 및 시스템의 저가화를 기대할 수 있다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.6
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• pp.533-539
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• 2004

In this work, in order to realize a band pass filter with wide-band characteristics for mobile communications, 2 GHz band pass filter was designed using ring resonator with stub. The three stage wide-band BPF was designed and fabricated. For broadband design, the ring circumference was divided by 4 sections with 1/8 wavelength and 2 sections with 1/4 wavelength which have different line impedances. The characteristics of the proposed BPF were highly improved by using three stage ring resonator. The characteristic impedance values of each sections were obtained by Powell's least square algorithm where differentiations are not needed. The measured results showed a good agreement with the theoretical results as well as ADS simulation.