• Journal of electromagnetic engineering and science
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• 제6권3호
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• pp.171-175
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• 2006

In this paper, a new semi-lumped low-pass filter with three finite attenuation poles at stopband is presented. The new structure is composed of a pair of symmetrical parallel coupled-line and a shunted capacitor. With this configuration, three finite attenuation poles can be available for 2nd, 3rd, and 4th harmonics suppression. The research method is based on transmission-line model for tuning the attenuation poles. In order to examine the feasibility of the proposed structure, a low-pass filter based on microstrip structure with harmonics suppression is designed, fabricated, and measured. The experimental results of the fabricated circuit agree well with the simulation and analytical ones.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.751-755
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• 2003

In this paper, We proposed compact multi-layer LTCC (Low Temperature Cofired Ceramic) bandpass filter for Bluetooth module. A ${\lambda}/4$ coupled stripline resonators are designed, which composed of coupled strip-line section and loading capacitance. This resonator with a loading capacitor has slow-wave characteristics. Due to the slow-wave effect of the proposed resonator, it is possible to design and fabricate a compact bandpass filter with a wide upper stop band. Attenuation poles in the lower stop band are achieved using controlling of electro-magnetic coupling between resonators. Using multi-layer LTCC technology, we designed and fabricated band pass filter with a finite attenuation pole and wide upper stopband. The overall size of the filter is $1.2{\times}2.0{\times}1.0mm^3$.

• 한국전자파학회논문지
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• 제16권4호
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• pp.438-446
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• 2005

본 논문에서 변형된 generalized Chebyshev 유리함수가 제시되었다. 이 함수를 이용한 회로망 합성으로 새로운 원형 저역 통과 필터의 소자값이 구해졌다. 이 제안된 필터는 기존의 generalized Chebyshev 필터와 마찬가지로 통과 대역에서 등리플을 갖지만 유한 주파수에서 오직 하나의 감쇠극을 갖는 기존의 필터와는 달리, 제안된 필터는 저지 대역에서 서로 다른 두 개의 감쇠극을 갖는다. 만약 고조파가 두 번째 감쇠극 주파수에 맞춰진다면, 고조파를 효과적으로 억제할 수 있다. 게다가, 두 번째 감쇠극의 위치는 임의로 조정될 수 있기 때문에 제안한 필터는 넓은 저지 대역 구현에 특히 유용하다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.628-631
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• 2003

In this paper, 2.4 GHz WLAN BPF(Band Pass Filter) using LTCC(Low temperature cofiring ceramic) multilayer technology was simulated and manufactured. A modified ${\lambda}/4$ Hair-pin resonator with shunt-to ground loaded capacitor is used to shorten resonator length and improve circuit Q factor. Proposed BPF has a combline structure. Electro-magnetic Coupling between coupled strip-line resonators is controlled to provide attenuation poles at finite frequencies. The overall size of the filter is $3.2{\times}1.6{\times}1.3mm^3$. The measured result shows good agreement with simulated data.