• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.419-428
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• 2000

Multiconductor transmission line(MTL) equations are solved by FDTD(Finite-Difference Time-Domain) method to predict crosstalk and fields to transmission line coupling on lossy multiconductor transmission lines terminated in arbitrary linear loads. Skin effect losses as well as dc losses are included in the analysis. In order to increase computational efficiency, the convolution integral of internal impedance of conductors and the line currents is computed by using Prony method. For boundary conditions of MTLs terminated in linear loads, state-variable formulation is adopted. The simulated results by FDTD method are compared with the measured ones obtained by using TEM cell. The predictions are in good agreement with the measurements. In addition, it has been found that skin effect losses as well as dc losses of the conductors should be included for accurate predictions on relatively high loss transmission lines such as PCB. It has also been found that dc losses and skin-effect losses affect late-time responses and early-time responses, respectively.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.11
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• pp.55-60
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• 2008

This paper proposed a dual-band RF switch using a Composite Right/Left Handed transmission line(CRLH TL) and PIN diode. RF switch is usually consist of $\lambda/4$ Right Handed transmission line(RH TL) and PIN diode. The dual band characteristics of RF switch was achieved by using CRLH transmission line instead of RH transmission line. CRLH Open-Stub was designed for resolve to reduction of isolation due to Package Inductance of PIN diode. The proposed RF switch was designed at GSM and DCS frequency-band. The measurement results showed a good agreement with theoretical result.

• Bulletin of the Korean Space Science Society
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• 1993.10a
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• pp.23-23
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• 1993

과학로케트에 탑재되는 x-선 검출기에서 검출되는 2 kev 에서 10 kev 사이의 x-선 신호를 분석하여 데이터를 얻고, 전송하기 위한 피로를 설계하고 제작하였다. 신호처리회로의 전체적인 구성은 2 - 10 key의 x-선 에너지 및 event time을 측정하는 회로 및8-선 계수율을 측정하기 위한 카운터회로를 위주로 설계하였으며, x-선 event의 에너지가 측정에너지를 벗어나거나 상승시간이 긴 신호는 anti-coincidence 회로를 통하여 제거되고, 그 계수율이 기록되도록 설계 제작되었다. 또한 신호처리회로에서 얻은 데이터는 telemetry를 통하여 serial 형태로 전송되어야 하므로 8086 microprocessor를 이용하여 데이터를 획득하고 전송하도록 하였다. 따라서 본 실험에서 제작된 신호처리회로의 기능 및 특성에 대해 논하고자 한다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.5
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• pp.75-82
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• 2013

This paper presents a PUF circuit based on the randomness of crosstalk magnitudes in adjacent transmission lines. Conventional PUF circuitry suffers the reliability problem where a consistent output value is not guaranteed due to environmental changes, such as power supply voltage and operating temperature. The proposed circuit consists of three transmission lines. The crosstalk difference between two transmission line pairs can be arbitrary. The proposed circuit compares the crosstalk differences between two transmission line pairs, and yields consistent responses. The crosstalk differences are immune to operating environment changes. The proposed PUF circuit provides with reliable responses for given challenges. It can be utilized by security systems such as authentication and encryption.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.4 s.107
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• pp.380-386
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• 2006

Electric fuel sender fur the vehicle fuel gauge system was designed and fabricated based on the CPW(Co-Planer Waveguide) transmission line theory. It is applied on this system that characteristic impedance of RF transmission line can be varied by the surrounded material of the line. By the characteristic impedance owing the level of gasoline or diesel fuel in vehicle fuel tank, CPW line has corresponding reflected signal as much as changed impedance. Detected signal is amplified, and delivered to fuel indicator into cluster unit on dash board. Conventional floating mechanical buoy level gauge has several defects as low reliability and high break down rate by mechanical operation, and has not good linearity for the fuel level difference. CPW line with electric circuits are constructed on 1.6 mm thickness epoxy substrate, and measurement shows that this system has more accurate level and better linearity than conventional mechanical system. New electric fuel sender which has good productivity with long lifetime and low-in-cost by the SMT chip assembling could be replaced this system with conventional floating buoy system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.2
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• pp.114-120
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• 2008

This paper proposed the band pass filter(BPF) with feeding structure using $\pi$-type transmission line by means of transforming the input/output coupled-lines of the half wavelength parallel coupled-line BPF into K-inverter, then substituting $\pi$-type transmission line equivalence for K-inverter. The proposed method supplies solution with what the half wavelength parallel coupled-line BPF's input/output coupled-lines are realized. Also it can quite reduce efforts and time needed to optimize filter performance when is compared to reported method using tapped line structure because formulas is very simple and accurate. On the basic of the proposed method, the BPF with feeding structure using $\pi$-type transmission line has been designed and fabricated. The validity of proposed method was proven by the measured result.

• The Journal of the Acoustical Society of Korea
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• v.32 no.4
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• pp.361-368
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• 2013

As one way to describe the behavior of a vibrating string, analogies to a transmission line have been made based on the fact that they have oppositely travelling waves on each of them. In such analogies, a rigid end to the string has been represented as an open circuit, and the displacement of the string as the current on the transmission line. However it turns out that the rigid end corresponds to a short circuit, the displacement to the voltage by the theory of the transmission line, and it is confirmed by experiments with circuit simulations. Based on these discoveries, a transmission line based plucked string model comprising a transmission line, two piecewise linear current sources, and switches is proposed. The proposed model is validated by showing that the voltage at the arbitrarily chosen location, and the voltage calculated over an infinitesimal portion at the end of the transmission line are consistent with the displacement at the corresponding location and the force on the rigid end of the string from the well known difference form of a wave equation governing the behavior of the string with its fundamental frequency tuned to that for the proposed model, respectively. Moreover, the applicability of the proposed model to modeling string and wind instruments is presented.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.8
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• pp.37-44
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• 2004

This paper describes a new GaAs-based surface-micromachined microstrip line supported by dielectric post and air-gapped signal line with ground metal. This new type of dielectric-supported air-gapped microstripline(DAML) structure is developed using surface micromachining techniques to provide easy means of airbridge connection between the signal lines and to archive low losses at millimeter-wave frequency band with wide impedance range. Each DAMLs with the length of 5 mm are fabricated and the measured characteristics are compared with those of the conventional microstrip transmission line. These transmission lines are composed of 10 ${\mu}{\textrm}{m}$ height of signal line, post size of 10 ${\mu}{\textrm}{m}$ ${\times}$ 10 ${\mu}{\textrm}{m}$ and post height of 9 ${\mu}{\textrm}{m}$. By elevating the signal lines from the substrate using the micromachining technology, the substrate dielectric loss can be reduced Compared with of the conventional microstrip transmission line showing 7.5 dB/cm loss at 50 GHz, the loss can be reduced to 1.1 dB/cm loss at 50 GHz.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.4
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• pp.353-361
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• 2016

This work presents an investigation of the radio frequency characteristics of an FTLPGS (fishbone-type transmission line employing periodic ground structure) fabricated on PES (polyether sulfone) for the realization of a transparent flexible wireless communication device. According to the results, the FTLPGS on PES showed a shorter wavelength characteristic when compared with a conventional coplanar waveguide. Concretely, the wavelength of the FTLPGS was 1.91 mm at 50 GHz, which was 48.5% of the conventional coplanar waveguide. The bandwidth extraction result showed that the passband of the FTLPGS on PES was 250 GHz. Unlike conventional periodic structures, the characteristic impedance of the FTLPGS on PES also showed a very low frequency dependency. A miniaturization of the RF circuit on the PES substrate was made possible by the FTLPGS on PES having shown characteristic impedance lower than that of conventional transmission lines. These results mean that, with a broadband operation frequency, the FTLPGS on PES is a suitable construction application for the transmission line and distributed passive components.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.2021-2022
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• 2006

Power-Line Communication (PLC)는 전력선을 채널로 이용한 통신 방법으로 별도의 전용선 설치 없이 통신이 가능한 기술을 말한다. 그러기에 오래전부터 연구가 진행되어 왔으며 최근에도 여전히 고속 전력선 통신에 관한 연구가 진행 중에 있다. 이에 본 논문에서는 이런 고속 전송을 위해 최근 연구가 활발한 고속 Ultra Wide Band (UWB) 전송기술을 전력선 통신에 적용하여 시뮬레이션한 후 결과를 통해 적용가능성을 확인한다.