• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2280-2282
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• 2001

EMV(electromagnetic valve) 시스템은 자동차에서 기계식 캠을 사용하지 않고 전자기력을 이용하여 흡·배기 밸브를 작동시키고 타이밍을 조절하기 위한 것이다. 본 논문에서는 EMV 시스템을 위한 전자기와 기계적 모델을 사용하여 그에 대한 동역학 모델을 유도하였다. EMV 시스템의 최대 동작주파수가 가솔린 엔진의 최대 회전수 6000rpm에 대응한 valve의 주파수가 50Hz 되기 위한 제어기를 설계하였고, 실험을 통하여 문제점들을 파악하고자 한다.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.181-184
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• 2003

Electromagnetic field simulator have been developed on Java 2 platform (J2SE) because provides robust solutions for applications as well as object oriented design. The simulator can be easily utilized with independent platform. Physical variables for the simulator can be controlled by the user. The numerical results are immediately displayed with graphical images in real time. Therefore, this simulator is intended to be used for education such as antenna engineering, microwave engineering, electromagnetic theory and so on.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.5 no.2
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• pp.39-45
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• 1994

Analysis and design procedure for three-line three port bandpass / bandstop fliter consisting of three line microstrip structures is reported. The measured results for experimental three port structure is shown to be in good agreement with theoretical poedictions.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.87-90
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• 2000

In this paper. we present a method for a systematic design of a dielectric slab polarizer in the circular waveguide. This structure is realized using a tapered dielectric slab inside a circular waveguide. Commercial software is used to obtain the equivalent dielectric constant of the circular waveguide partially filled with a dielectric slab. The length of the tapered region is determined so that the reflection from the dielectric slab is sufficiently low. A polarizer operating at 10 GHz band is designed, fabricated and tested.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.91-95
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• 2002

This paper describes the design of planar circulators with propellers resonator including a plurality of symmetric magnetic walls. One purpose of the paper is to present insertion loss on this resonator for magnetic loss, dielectric loss, magnetic field and saturation magnetization. Another is to study the effect of propeller resonator on response characteristics. The paper includes the description of one commercial circulator that is compatible with the data obtained

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.205-208
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• 2002

This paper presents a quantitative analysis on the intermodulation product between transmitter W-CDMA leakage signal and receiver out of band blocker, and proposes design guide lines for overcoming the effect in receiver design. Our analysis shows that duplexer isolation, attenuation and LNA IIP3 are mainly responsible for the 3rd order intermodulation product. Analysis also shows that LNA IIP3 required for meeting 3GPP TS 34.121 specification is about 1 ㏈m with duplexer isolation of 50 ㏈ and duplexer attenuation of 24㏈.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.7-10
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• 2002

This paper presents a design of 24㎓ GaAs MESFET voltage controlled oscillator using a dielectric resonator(DR) and a frequency doubler. DR modeling has been done to get the effects of resonator size and the gap from transmission line by HFSS at 12㎓, and frequency doubler is used to get 24㎓ Output.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.278-282
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• 2002

In this paper, a dual-band CPW antenna is designed with the aid of Genetic Algorithm and Finite-Difference Time-Domain method. The design goal is to minimize the magnitude of S$\sub$11/ in the frequency band between 1.8㎓ and 2.4㎓. The resonance frequencies are shifted by about 80MHz and 50MHz from the desired frequencies at 1.8㎓ and 2.4㎓ respectively. But the bandwidth agrees well with that of Simulation.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2002.11a
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• pp.215-218
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• 2002

In this paper, a dual-frequency printed slot antenna loaded with an open-ring conducting strip and capacitively fed by a coplanar waveguide(CPW) is designed. The designed antenna has a bandwidth of 240㎒(1690㎒-1930㎒) at PCS frequency band and of 160㎒(2380㎒-2540㎒) at WLAN frequency band. In both frequency ranges, pattern and gain requirements are satisfied. The commercial software, IE3D, was used to design slot antenna. The predicted characteristics along with measured data are presented for verification purpose.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2001.11a
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• pp.44-48
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• 2001

In this paper we describe the design of symbol timing and carrier synchronization algorithms for burst receiver. The demodulator consists of digital down converter, matched filter and synchronization circuits. For symbol timing recovery we use modified Gardner algorithm. And we use decision directed method for carrier phase recovery. For the sake of performance analysis, we compare simulation results with the board implemented by FPGA which is APEX20KE series chip for Alter. The performance results show it works quite well up to the condition that a frequency offset equal to 0.1% of symbol rate.