• Journal of Advanced Navigation Technology
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• v.14 no.1
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• pp.33-40
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• 2010

In this paper, the bit-error-ratio (BER) performances of Digital Radio Mondiale Plus (DRM+) system which stand for the European standard to bring analogue FM radio to digital radio in Band-II(30-170 MHz) are evaluated under multipath fading channel models used in Band-II and the adjacent channel interference (ACI) caused by FM signal. From the simulation results, the DRM+ system shows robust performances under time-varying channel environments even though the speed of a vehicle is equal to 300km/h. And it is shown that the frequency diversity, determined by delay spread of multipath fading channel, increases the coding gain of the DRM+ system with an increase of delay spread. In addition, to guarantee the BER performance of 10-4 for DRM+ system with ACI due to FM signal, the simulation results show that the desired signal-to-ACI power ratio must be more than -30 dB when the carrier frequency distance is 150 kHz.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1999.11b
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• pp.167-172
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• 1999

DAB는 기존의 아날로그 대역을 사용하게 됨에 따라 기존의 FM 방송신호의 간섭으로 수신성능의 저하가 예상된다. 본 논문에서는 FM신호의 간섭에 따른 DAB시스템의 성능저하를 SNR의 관점에서 성능평가를 하였으며, DAB와 FM신호간의 혼신보호비를 제시하였다.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1119-1122
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• 1990

Presnted is a new optical transmission system to transmit the FM control signal (80 MHz) through an optical fiber by the use of an inexpensive LED having a cutoff frequency of as low as 30 MHz. Studies are carried out on the division of the FM signal frequency at 80 MHz by a factor of four. The FM signal frequency is, after the transmission through the optical fiber, then multiplied by a factor of four so as to obtain the normal FM control signal.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.22-32
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• 2010

Increasingly advanced Information Technology (IT) has changed the operator so as to create more diversified and advanced traffic information demand. To deal with the changing demand in private sector, a concept of on-demand traffic information has been rapidly introduced. However VMS, a product of the first generation of ITS, which was designed to provide the unspecified individuals during driving the car with the basic level of traffic information by the public failed to actively change itself in such a changing pattern. This study was intended to describe the VMS system (tentatively, FM-VMS) which was further developed to accommodate the needs favoring the sophisticated PDA with the public role of providing the unspecified individuals with the equal information. FM-VMS introduced in this study is the device designed to transmit the voice and message to the drivers through the radio information device mounted on a car. A core technology is, unlike FM-DARC and RDS, the Water Making technology which directly inserts the digital signal into FM frequency in use. It's been currently used for broadcasting and security purpose. A detection rate as a result of testing FM-VMS system using Water Making technology was 90% or more in voice and message within 20m from test VMS. When a public-developed VMS information could be transmitted using FM frequency to the relatively vulnerable users (vulnerable to traffic information) in voice on a real-time basis to provide the regional traffic information, and furthermore, VMS message could be received through radio liquid using FM frequency only, it would obviously bring about the innovation in ITS as well as pave the way for creating the new added value down the road.

• Aerospace Engineering and Technology
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• v.2 no.2
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• pp.76-82
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• 2003

To guarantee the proper functions of a satellite in the extreme space environment, the several test models are developed generally. There are advantages that the design and the analysis of Flight Model(FM) can be validated through these test models, and the functional reliabilities can be increased by reflecting the modifications on the final design of FM. The integration and test of Structure & Thermal Model(STM) of KOMPSAT, being currently developed, have been completed. In this paper, the processes of design and analysis of the STM propulsion system, one of the KOMPSAT modules, are described.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.111-114
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• 1996

FMS(Flexible Manufacturing System)는 NC와 같이 다양한 종류의 공정을 수행할 수 있는 가공장비들이 자동화된 물류 운반 시스템(Material Handling System)으로 연결되어 있어 집중화된 제어 및 운용 시스템에 의해 여러 종류의 다양한 부품들을 동시에 가공할 수 있는 생산시스템으로 정의할 수 있다. FMS의 도입을 고려 중인 기업이 초기단계에서 가장 먼저 직면하게 의사결정 문제는 부품선정 문제이다. 즉, 현재 생산하고 있는 부품들 중에서 혹은 새로이 생산할 부품들 중에서 어떤 부품을 가공할 것인가를 결정하여야 한다. 이 문제의 중요성은 부품선정문제가 FMS의 운영에 필요한 가공장비, 치구 및 공구의 소요량 결정과 관련을 갖게되고 결과적으로는 FMS의 경제적 타당성 평가에 근본적인 영향을 미치게 된다. 본 연구에서는 FMS의 초기설계단계에서의 부품선택문제의 해결을 통한 FMS 경제적 타당성을 평가할 방법론 및 해결 방법을 제시할 것 이다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1169-1174
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• 2002

In this paper, we implemented the sign board system that displays user's image, user's sentence, the information from DARC. The existing sign board is displaying only user's image and sentence. Or other existing sign board is displaying the information via CDMA network. However, our system is also able to display the user's message like other system and gain the information more cheap by DARC. This system includes the main processor, the program memory, the external memory, the DARC module and the LED display module. The external memory stores the user's message files and the order file that decides the displaying order of user's file and the DARC information The DARC module extracts the DARC information from FM signal. From the experiment, we could confirm that this system display the DARC information and the user's message by the order file.

• The Journal of the Acoustical Society of Korea
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• v.12 no.1
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• pp.27-36
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• 1993

FM방식의 악기음원합성은 해당 악기의 음색과 음정에 맞는 FM의 기본 주파수와 변조 계수를 정하여 신호 파형을 생성하는 것으로, 다른 가, 감산방식 또는 PCM방식 등에 비해 비교적 간단한 구조로 다양한 악기음원합성이 가능하다. 따라서 현재 사용되고 있는 개인용 컴퓨터에 부착되는 사운드합성 카드에는 FM방식 음원합성기술이 적용되고 있다. 본 논문에서는 FM방식 음원합성기술을 이용하여 실시간 악기음원합성이 가능한 논리회로를 설계하는데 관한 연구를 기술한다. 본 연구에서는 소프트웨어 프로그래밍에 의해 FM방식 음원합성기의 구조를 설계하고 주요 블록의 최적 변수 값을 실험하였다. 논리회로 설계 및 회로검증은 향후 주문형반도체(ASIC:Application Specific Integrated Circuit)제작을 위해 기존의 표준셀 라이브러리와 주문형반도체 전용 설계시스템을 사용하였다. 회로검증 결과는 간이 평가보드를 제작하고 PC와 접속시켜 생성된 악기음을 직접듣는 주관적 평가방법으로 최종 확인하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.8
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• pp.758-769
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• 1991

We have investigaed the radio data system which is used for the VHF/FM streo broadcasting system. The RDS system has the I6 important service features which is given by the digital multiplexed modulation method above the FM stereo baseband spectrum. The related cicuit system and general-purpose micro-controller have been applicated for the demodulation and processing of transmitted digital information at the rate of 1187.5bps, and we have developed the receiver system which performs the primary 5 features. The develpoed system has the complete compatibility with the conventional FM-car stereo receiver, we have analyzed the received RDS signal via the hardware implementation.

• The Journal of the Acoustical Society of Korea
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• v.14 no.3
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• pp.105-113
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• 1995

For the case of using analog FM system and CDMA system together in the mobile communications, we experimentally calculate the appropriate frequency offset to improve the frequency efficiency by analizing the interference between both systems. As the results of the analysis, we obtained that frequency offset is 840KHz(Path Loss : 80dB) and 720KHz(Path Loss : 120dB) for the Path Loss when a output of CDMA Base Station is 0.91 W ERP. Therefore, to minimize the frequency offset, a output of Base Station will be controlled corresponding to Cover Area.