• 제목/요약/키워드: Modem.

검색결과 1,811건 처리시간 0.025초

무선 유비쿼터스 통신을 위한 재구성 MMIC VCO 설계 (Reconfigurable MMIC VCO Design for Wireless Ubiquitous Communications)

  • 강정진;김완식;이동준
    • 한국인터넷방송통신학회논문지
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    • 제8권2호
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    • pp.67-73
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    • 2008
  • Reconfigurable radio technology is needed to reconstruct frequency and modem functionality, which can be different within various regions. In addition, it makes it possible for a single mobile handset to support various standards of wireless communication, and thus plays a key role inmobile convergence. A MMIC VCO(Monolithic Microwave Integrated Circuit Voltage Controlled Oscillator) has been developed to produce high power and wide bandwidth that adapts the Clapp-Gouriet type oscillator for series feedback. We were fabricated based on the 0.15um pHEMT from TRW. The MMIC VCO was connected to an alumina substrate on the carrier for testing. This MMIC VCO module shows good performance when compared with existing VCOs. Futhermore, it has potential as a reconfigurable MMIC VCO for ubiquitous communications such as LMDS (Local Multipoint Distribution Service), VSAT, Point to Point Radio and SATCOM.

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$\cdot$무선통신을 이용한 해양환경 모니터링 시스템의 개발 (Development of a sea environmental monitoring system using wire and wireless communication)

  • 김진호;한정만;김상봉
    • 한국해양공학회지
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    • 제10권4호
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    • pp.160-165
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    • 1996
  • This paper introduces a sea environmental monitoring system for measuring pH,DO, level and temperature. This system is developed using a personal computer(PC) and multiple single board computers. A PC communicates with the single board computers by awireless communication method and transfers data to another personal computer for processing data by a modem. The values of pH,Do,level and temperature, which are basic components to estimate sea environment, are real-timely processed in the single board computer at each stations, and transferred to the monitoring PC. These data are graphically shown on the PC monitor and logged on the data processing system in the form of file. Using the wire and wireless communication system, user can constantly analyze the acquired data and detect the sea contamination.

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D/A 젼환기의 비선형왜곡을 보상하는 Echo Canceller (Echo canceller compensating a nonlinear distortion of D/A converter)

  • Jeong, Gi-Seog
    • 전자공학회논문지A
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    • 제32A권3호
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    • pp.10-17
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    • 1995
  • this thesis proposes a new echo canceller that can be used in a fulll-duplex digital subscriber loopmodem. The modem suffers from nonlinear distortion such as transmitted pulse asymmetry, saturation in transformers, and nonlinearity of data converters. The proposed nonlinear echo canceller can compensate the nolinear distortion by using a nonlinear digital filter based on canonical pieceewise-linear (CPWL) function. Numerical results based on computer simulation are given in this paper. It is shown that the convergence characteristics depend on the initial values of weights of linear filters with absoluters and that the nonlinearity in digital-to-analog(D/A) converter can be compensated by a relatively small number linear filters with absoluters. It is also shown that the proposed algorithm has a faster convergence rate in comparison with Voterra algorithm.

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수중 초음파 다중통신 네트워크를 위한 MAC 프로토콜에 관한 연구 (A Study on the Mac Protocol for Multichannel Network Underwater Acoustic Communication)

  • 김천석
    • 한국전자통신학회논문지
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    • 제1권1호
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    • pp.42-48
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    • 2006
  • 본 논문에서는 해저의 이동체 사이의 효과적인 다중 초음파 데이타 통신을 위한다중 초음파 접속제어 프로토콜을 제안 하였다. 논리계층에서의 프로토콜은 모선과 수중 이동체간에 다중 채널 통신이 가능하고 논리계층간의 peer to peer 통신이 가능함을 확인하였다. 본 논문에서 제안된 접속제어 프로토콜은 수중 통신 시스템의 여러 가지 수중 물리적 환경에서 전파지연 시간에 무관하게 최대 수율을 보장하고 서로 다른 주파수 대역을 사용하는 다중 전송채널을 이용하여 수중에서 고속 데이터 전송의 가능함을 확인하였다.

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영동북부지역 전통민가의 변화에 관한 연구 - 왕곡마을을 중심으로 - (A Study on Traditional Fork House of Change in Northern part Young-Dong Region - the case of wang-gok villages -)

  • 임하나;김경호
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2004년도 추계학술대회 논문집
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    • pp.277-282
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    • 2004
  • A Study traditional folk house and primary factor from investigation of Wang-Gok villages space composition program which is contains regional color, economy, rationality. From that's all, Analysis the effect of modern life style to folk house space pattern change and a primary factor of northern traditional fork house type of Korea. 1. Analysis and arrangement space composition structure about natural${\cdot}$geographical${\cdot}$cultural environment. 2. Examination existing commoner's house research by a region, space program for understanding house pattern, specially double rows which are partitioned by walls in northern part of Young-Dong region. 3. Analysis folk house character and object house information. by the way, Investigation changing of commoner's house space program with modem life style.

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물리적 특성에 따른 공동주택에서 도로교통소음의 추정모델에 관한 연구 (A study on Providing the Estimation of the road traffic noise in the apartment according to physical characteristics)

  • 장정희;이강희;김곤
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2003년도 정기총회 및 추계학술대회
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    • pp.89-93
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    • 2003
  • The ambient noise in modem society is the factor to give people serious influence. Noise barriers installation is mostly used in the apartment estate to protect countermeasure about the road traffic ambient noise. The purpose of this study is to suggest reference data fur design of traffic noise reduction in apartment estate. It finds out how the traffic noise is measured about a noise barriers and physical characteristics. The 57dB was measured from the noise barriers in a 2m point. An ambient noise's of the part to belong noise attenuation is big at the sound arresting area of the noise barriers as the distance far.

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전통한옥의 도시집합주거로 발전 가능성 연구 (A Study on the Possibility of Model Development from Traditional Han-ok to Urban Clustering Housing Model in Korean Context)

  • 손승광
    • 한국주거학회논문집
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    • 제19권3호
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    • pp.71-81
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    • 2008
  • A traditional Korean housing is a typical type which is contained life style, spatial organization and scape element of people who lived in Korea. In the hanok, people want to be live not only in human environment and traditional culture, but also modem urban housing as a high density. This article deals as follows: First, Hanok as urban housing would be composed in a housing lot, linear type layout, devide building, and cluster type. Second, Housing unit and configuration of Multi family housing can be used single story, second story, second story + single story, multi story and Hanok roofing. Thirds, structure of the building are traditional wooden, combined one of steel and wood or concrete and wood, and the building system in exterior and interior can be seperated into another system. Forth, Image of multi story Hanok A last, consistency of Hanok is not a repeat of an origin but application and creative aptitude of the origin, and multi family housing application of Hanok can be a trial creative.

상수도 원격 검침 데이터 송수신 위한 Client/Server 소켓 프로그램 개발 (Development of a Client/Server Socket Program using Remote Measurement of Digital Water Meters)

  • ;박용만;권종원;김희식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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    • pp.153-155
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    • 2006
  • An automatic remote water measurement system was developed. This system sends automatic remote measured and collected water meters data automatically from the transmitter with CDMA modem through SK-Telecom network The water meter data are received through LAH TCP/IP and displayed as test file on IE(Internet Explorer) window. The existing water meters of mechanical type have so many problems to measure data. The person must visit the location of each water meters and write down the data records manually. In this system the RF module has attached each water meter Client/Server programs are developed by network socket programming.

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유한요소법에 의한 권철심변압기의 철손해석 (Analysis of Iron Loss in a Wound Core Type Transformer by FEM)

  • 권병일;김성영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.21-23
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    • 1995
  • The analysis of the thin lamination model of the wound core type transformer by FEM requires many region division and much calculationg time, and it has difficulty in calculation by modem computer. A new method which is simulated by a solid but anisotropic block with the magnetic permeabilities in the orthogonal dimension, is selected to account for the presence of the lamination.[1] Based on this equivalent anisotropic block model, we analyze the iron loss of the wound core type transformer by FEM, and compare the simulation results with the experimental results.

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전력선 버스를 이용한 제어시스템의 최적통신모뎀에 관한 연구 (A study of optimal data transmission modem for control system using Power-distribution circuit)

  • 정창경;박영철;손동섭;강정석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.496-498
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    • 1995
  • A power line data transmission method has been developed and presented in this paper. Although there have been efforts to develope power line data transmission techniques, none of them has been accepted as a standard. Thus, our method follows a defacto standard CENELEC's recommendations. The paper presents the algorithm as well as experimental results.

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