• 한국통신학회:학술대회논문집
• /
• 한국통신학회 1991년도 추계종합학술발표회논문집
• /
• pp.119-122
• /
• 1991

In this paper, a new adaptive IIR notch filter employing all pass filter is proposed. Proposed all pass filter is composed of all pole and all zero sections, each of which utilizes modulation lattice filter [11]. And, adaption algorithm for proposed notch filter is also derived. In addition, the error surface for proposed IIR adaptive notch filter is analyzed. Computer simulation results reveal that the proposed adaptation algorithm works well for low SNR(signal to noise ratio) single and multiple sinusoids. And it is shown that for estimation time varying frequency, the parameter which is related to notch bandwidth is important than any other parameters.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
• /
• pp.710-713
• /
• 2004

The design, simulation, modeling and measurement of a low temperature co-fired ceramic (LTCC) RF switch module for GSM applications is presented in this paper. RF switch module is constructed using a Rx/Tx switching circuit and integrated low pass filter. The low pass filter function was designed to operate in th GSM band. Insertion and return loss of the low pass filter were designed less than 0.3 dB and better than 12.7 dB at 900 MHz. The RF switch module contained 10 embedded passives and 3 surface mount components integrated on $4.6{\times}4.8{\times}1.2$ nm, 6-layer multi-layer integrated circuit. The insertion loss of switch module was measured at 900 MHz was 11 dB.

• 전자공학회논문지
• /
• 제50권11호
• /
• pp.36-40
• /
• 2013

본 논문에서는 덤벨형 결함 접지면 구조를 갖는 복합 좌-우향(CRLH) 전송선로를 이용하여 초광대역 대역통과 여파기를 설계하였다. 결함 접지면 구조와 마이크로스트립 인터디지털 캐패시터를 이용하여 CRLH 전송선로를 구현하고 이것을 이용하여 필터를 설계하였다. CRLH 전송선로는 저역통과와 고역통과 필터의 복합적인 특성을 나타내는데, 그것들의 차단주파수를 잘 조절함으로써 초광대역의 대역통과 필터의 특성을 얻을 수 있다. UWB 필터 특성을 얻기 위해 1, 2, 4, 8 셀을 갖는 CRLH 전송선로에 대해 시물레이션하였고, 본 논문에서는 결과를 검증하기 위해 4 셀 구조의 UWB 필터를 설계 제작하였다. 측정된 결과는 시뮬레이션 결과와 일치하며 5GHz 중심주파수에서 88%의 넓은 대역폭을 갖는다.

• 대한전자공학회논문지
• /
• 제23권6호
• /
• pp.950-956
• /
• 1986

In this paper, a direct addressing mode of a microprocessor is introduced to save memory capacity, and also a dedicated digital filter is constructed to speed up the filter processing and to enable an easy selection of the impulse response types. A theoretical analysis has been conducted on the errors caused by the finite word klength, rounding-off and multiplication procedures. The digital filter designed by the proposed method is made into a module which can function as a 7th-order recursive or a 14-order nonrecursive type with a simples witch operation. The proposed filter is implemented on a printed-circuit board. The frequency characteristics of this filter can be controlled by the multiplication values stored in ROMs. A low-pass, a high-pass and a band-pass filter have been designed and their frequency characteristics are verified by actual measurements. For a order higher filer, two filter modules have been cascaded into an integrated filter of 23rd-order non-recursive low-pass type and a 12th-order recursive multiband type. Their frequency characteirstics have been found to agree with the theory.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.1345-1347
• /
• 2008

This paper described a method of determining whether arcing is present in a low-voltage wiring system. We simulated the series arcing that generated in electrical loads and fabricated a arc detection module which can discriminate between normal and arcing state. The module consists of a high-pass filter with a low cut-off frequency of 3 kHz to attenuate power frequency voltage and an active band-pass filter with a frequency of 4 kHz ${\sim}$ 8 kHz to detect series arc signals only. We tested an Incandescent lamp that was controlled by a dimmer and analysed. The module consists of a high-pass filter with a low cut-off frequency of 3 kHz to attenuate power frequency voltage by 80 dB and an active band-pass filter with a frequency of 4 kHz to detect series arc signals only. From the experimental results, we could detect series arc signals without an influence of non-linear loads.

• 한국통신학회논문지
• /
• 제22권7호
• /
• pp.1385-1393
• /
• 1997

In this paper, a systematic design method of brjoadband tunable bandpass filter is presented by using user defined varactor diode method. The tunable bandpass filter is constructed as the cascade connection of low pass filter and high pass filter. The designed filter shows the characteristeristics of 2.7.+-.0.2dB insertion loss and 37.1.+-.5.0dB insertion loss and 32.1.+-.2.2dB image rejection. The results of the research can be used fodr the broadband tunable filter of DBS tuner and communication instruments.

• 대한전자공학회논문지
• /
• 제25권2호
• /
• pp.227-232
• /
• 1988

A semicustom VLSI design fo digital filters used in TDM/FDM transmultiplexer is described. A filter bank composed of only all-pass digital filter sections are implemented with the polyphase network. The use of all-pass filters as basic building blocks is shown to provide a trans-multiplexer structure that has low computational requirements, low quantization noise, and high modularity. The silicon compiler system is used to reduce the design time and to increase the credibility of designed filters. As a prototype, 1st and 2nd order all pass filter are designed, using CMOS N-well double metal technology. The chip sizes of first order filter and the second order filter are 2652 x 533\ulcorner\ulcorner 5334x4300\ulcorner\ulcorner respectively.

• 한국컴퓨터정보학회논문지
• /
• 제21권11호
• /
• pp.23-30
• /
• 2016

In this paper, we propose an adaptive histogram projection technique for dynamic range compression and an efficient detail enhancement method which is enhancing strong edge while reducing noise. First, The high dynamic range image is divided into low-pass component and high-pass component by applying 'guided image filtering'. After applying 'guided filter' to high dynamic range image, second, the low-pass component of the image is compressed into 8-bit with the adaptive histogram projection technique which is using global standard deviation value of whole image. Third, the high-pass component of the image adaptively reduces noise and intensifies the strong edges using standard deviation value in local path of the guided filter. Lastly, the monitor display image is summed up with the compressed low-pass component and the edge-intensified high-pass component. At the end of this paper, the experimental result show that the suggested technique can be applied properly to the IR images of various scenes.

• Journal of Mechanical Science and Technology
• /
• 제17권4호
• /
• pp.511-520
• /
• 2003

In room acoustics, reverberation time is an important acoustic parameter. However it is often difficult to measure short reverberation times at low frequencies with a traditional band pass filter bank if the product of filter bandwidth (B) and reverberation time (T) is small. It it well known that the minimum permissible product of bandwidth and reverberation time of the traditional band pass filter is at least 16. This strict requirement makes it difficult to measure short reverberation times of an acoustic room at low frequencies exactly. In order to reduce this strict requirement, in the previous paper, the wavelet filter bank was developed and the minimum permissible product of bandwidth and reverberation time was replaced with 4. In the present paper it is demonstrated how the short reverberation times of an practical room at low frequencies are successfully measured by using the wavelet filter bank and the results are compared with the traditional method using a band past filer bank.

• 한국시뮬레이션학회논문지
• /
• 제10권4호
• /
• pp.21-30
• /
• 2001

In this paper, EMI measurement, the STGU simulation being conducted, filter design, its characteristics, and its implementation to the PCB, and finally test results are discussed. When the low pass filter was implemented within the STGU, the power of EMI decreased more than 20dBm. Finally, when TE and MTIE, two important quality measure in synchronous reference clock, was assessed, ITU-T G813 requirement was satisfied. EMI(Electromagnetic Interface) is a measure of electomagnetic radiation from equipment in the range of 10KHz to 3GHz, and can cause unexpected reactions of electronics/electrical equipment. In this study, for safe and stable communication operation, a STGU (System Timing Generation Unit), which is a 2.5G SDH System and a major EMI source, was employed to simulate electromagnetic interface. Using Open-Site test, the power of fundamental frequency of EMI of interest and its harmonics were measured. Also, a low pass filter at cut-off frequency of 2GHz was specifically designed for this study to minimize the effect of EMI between electronic components.