• 한국정보통신학회논문지
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• 제4권4호
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• pp.825-834
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• 2000

본 논문에서는 비아-홀 접지를 고려한 K-대역 인터디지트 대역통과필터를 설계하였다. 중심 주파수가 19.6GHz에서 25~30%대역만을 통과시키기 위해 6차 인터디지트 대역통과 필터를 마이크로 스트립라인으로 구성하였으며 비아-흘의 수에 따른 필터의 특성을 분석하였다. 비아-흘 접지와 인터디지트 대역통과필터는 설계 최적화 과정을 통하여 통과대역에서 중심주파수와 대역폭관계를 만족시킬 수 있었으며 실제 제작후 측정결과 중심주파수는 19.150Hz 삽입손실은 -4.IdB, 반사계수는 -16.7dB로 비아-홀 접지의 영향을 고려한 설계가 이루어짐을 증명하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.191-194
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• 1999

Recently, with the rapid development and demand for compactness of portable communications, the requirement for compact and low-cost filter is increasing. One of the methods for reducing size and cost is to use high dielectric constant and low loss dielectric material in filter. The other is new monoblock dielectric band-pass filter (BPF) which has holes in a single dielectric body without additional coupling elements. This structure effectively reduces the size and cost of the filters. For previous conventional coaxial type dielectric BPF, dielectric substrates were used for coupling between adjacent resonators and additional input and output ports were needed. Coupling between adjacent resonators of monoblock BPF can be otained via electrode pairs. Capacitances of electrode pair structure for coupling are intensively investigated by 3-D FEM. The BPF for PCS has been designed to have a 30 MHz pass-bandwidth with center frequency of 1855 MHz and an attenuation pole at below the passband using a commercial 3-D structure simulator.

• 전자공학회논문지S
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• 제34S권10호
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• pp.80-88
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• 1997

This paper describes a design of a Wavelet Adaptive Filter(WAF) for the removal of the baseline wandering and the minimization of the signal distortion using by wavelet transform and adaptive filter in the ECG signal. WAF consists of two parts. The first part is wavelet transform that decomposes the ECG signal into seven frequency bands using Vaidyanathan and Hoang wavelet. The second part is adaptive filter that uses the signal of seventh low frequency band among the wavelet transformed signals as primary input and a unit impulse sequence as reference input. For the evaluation of the performance of WAF, we used several baseline wandering elimination filters such as commerical standard filter with cutoff frequency of 0.5Hz and general adaptive filter. We made use of MIT/BIH database and real patient data for the evaluation. In conclusion, WAF showed a lower ST segement distortion than standard filter and adaptive filter and has a higher eliminated noise power than standard filter and adaptive filter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1922-1924
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• 1999

The purpose of this study is to establish the design theory of a DR ceramic bandpass filter used for basestations and to research on the design theory of bandpass filter. The design procedure is circuit parameters and structural parameters will be derived. It was observed that the filter characteristics at the simulations.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권7호
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• pp.332-334
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• 2006

In this paper, we present an equalization scheme for 8-VSB signals for the ATSC DTV system. We propose a complex feedback filter and complex feedback sample generator for DFE to equalize 8-VSB signals in order to efficiently remove multipath distortions causing leakages from the qudrature component. We show that the proposed structure outperforms the conventional DFE used for the digital VSB which uses a real-valued feedback filter with real-valued decisions.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.827-830
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• 2003

This paper proposes an area-efficient FIR filter architecture for sampling rate conversion of hi-fi audio data. Sampling rate conversion(SRC) block converts audio data sampled at 96KHz down to 48KHz sampled data and vice versa. 63-tap FIR filter coefficients have been synthesized that gives 100dB stop band attenuation and 5.2KHz transition bandwidth. Time-shared filter architecture requires only one multiplier and accumulator for 63-tap filter operation. This results in huge hardware saving of up to 10~19 times smaller compared with traditional FIR structure.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권3호
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• pp.172-177
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• 2009

In this paper, a new morphology-based homomorphic filtering technique is presented to enhance features in medical images. The homomorphic filtering is performed based on the morphological sub-bands, in which an image is morphologically decomposed. An evolutionary design is carried to find an optimal gain and structuring element of each sub-band. As a search algorithm, Differential Evolution scheme is utilized. Simulations show that the proposed filter improves the contrast of the interest feature in medical images.

• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2000년도 하계종합학술대회논문집
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• pp.357-360
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• 2000

In this paper, we want to implement a noise canceller by using FIR filter on DSP(Digital Signal Processor). The FIR filter was designed by Blackman window together with desired band width and center frequency. We adopt Motorola DSP56002 and Crystal CS4215 (A/D and D/A converter) for our purpose. we generate input sinusoidal signals and noises by differential equations and pseudo random sequences on DSP also. The input signal including sinusoidal and noise passes through the FIR filter. The FIR filer output is a sinusoidal signal with noise reduced.

• 한국정보통신학회논문지
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• 제4권5호
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• pp.997-1003
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• 2000

유한길이 신호가 M-대역 직교 웨이브렛 필터로 구성된 QMF 뱅크의 입력인 경우, 이의 재생신호의 경계영역들은 완전히 재생되지 않는다. 따라서 경계영역신호를 완전히 재생하기 위해서는 경계영역에는 새로운 형태의 필터를 적용하여한다. 본 논문에서는 M-대역으로 분해된 신호가 입력신호와 같은 차원을 가지는 경우 경계영역 을 완전히 재생할 수 있는 경계필터의 설계방법을 제안하였다. 제안된 경계필터는 파라유니터리 행렬의 완전재생조건을 이용하여 설계되었다. 제안된 경계 필터를 부대역 부호화에 적용하여 모의실험한 결과 반사기법을 이용한 경우에 비하여 약 5%의 성능이 개선됨을 알 수 있었다.

• 대한전자공학회논문지TC
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• 제48권3호
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• pp.68-73
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• 2011

본 논문은 평행 결합 선로와 FLCLM(Frquency Locked Controlled Length Method)을 이용하여 저주파의 기생 신호 와 2차 고조파가 억압된 소형 협대역 개방형 스터브 대역통과 필터에 대하여 새롭게 제안 하였다. 평행 결합 선로의 특징은 저파주대역의 기생 신호와 2차 고조파를 억압 할 수가 있다. 최종 설계한 필터의 실험 결과에서 사용되는 대역의 중심 주파수는 5.8 GHz 이고 대역폭 10 % 이며 삽입 및 반사 손실은 각각 1.2 dB 및 14.8 dB 이다. 추가적으로 저주파 및 고조파 억제는 각각 28.9 dB 및 28.8 dB 이다.