• 제목/요약/키워드: Wireless Communication Systems

검색결과 2,142건 처리시간 0.026초

테스트베드상에서 LTE기반 철도 무선통신시스템의 성능 측정 (Performance Measurement of LTE based Railway Wireless Communication Systems in the Testbed)

  • 김범곤;권병희;조한벽;조웅
    • 한국전자통신학회논문지
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    • 제12권5호
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    • pp.755-762
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    • 2017
  • 철도통신에서 데이터의 전송속도를 향상시키고 신뢰성 있는 데이터 전송을 위해 LTE기반 철도 무선통신시스템에 대한 연구가 진행되고 있다. 본 논문에서는 LTE기반의 철도 무선통신시스템의 테스트베드에 대해 소개한다. 테스트베드상에서 무선통신시스템을 이용하여 전계강도, 통신 도달거리, 통화설정시간, 핸드오버 성공률, 데이터 전송속도 등과 같은 기본적인 통신성능 측정결과에 대해 소개한다. 이 결과를 바탕으로 향후 시스템 상용화에 필요한 사항들에 대해 논의한다.

유무선 통신에서의 제어 이론 적용에 대한 연구 개관 (Survey on Applications of control Theories to Wired and Wireless Communication)

  • 권욱현;김형석
    • 제어로봇시스템학회논문지
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    • 제6권8호
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    • pp.652-658
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    • 2000
  • Wired and wireless communication technique is growing rapidly. As the number of communication users is larger problems such as network congestion and signal interference between users are getting most important, There have been researches that try to solve them by control theoretic approaches. They apply various control theories to the control issues of communication. this paper surveys these researches and classifies them into ATM TCP/IP and wireless communication according to the target. The feedback control model of each communication protocol is shown and related researches are summarized and analyzed.

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Analyses of Characteristics of U-Healthcare System Based on Wireless Communication

  • Kim, Jung Tae
    • Journal of information and communication convergence engineering
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    • 제10권4호
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    • pp.337-342
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    • 2012
  • The medical industries are integrated with information technology with mobile devices and wireless communication. The advent of mobile healthcare systems can benefit patients and hospitals, by not only providing better quality of patient care, but also by reducing administrative and medical costs for both patients and hospitals. Security issues present an interesting research topic in wireless and pervasive healthcare networks. As information technology is developed, many organizations such as government agencies, public institutions, and corporations have employed an information system to enhance the efficiency of their work processes. For the past few years, healthcare organizations throughout the world have been adopting health information systems (HIS) based on the wireless network infrastructure. As a part of the wireless network, a mobile agent has been employed at a large scale in hospitals due to its outstanding mobility. Several vulnerabilities and security requirements related to mobile devices should be considered in implementing mobile services in the hospital environment. Secure authentication and protocols with a mobile agent for applying ubiquitous sensor networks in a healthcare system environment is proposed and analyzed in this paper.

이동통신 인프라 전력절감을 위한 부하관리 시스템 (Load Management System for Reducing the Power Consumption of Mobile Communication Infrastructure)

  • 이성재;강상기;이관호;유호상
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2014년도 춘계학술대회
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    • pp.841-843
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    • 2014
  • 이동통신은 폭발적으로 증가하고 있는 무선데이터의 수요를 충족시키기 위해서 WCDMA, Wibro, LTE 등의 통신 방식으로 발전하고 있다. 이들 이동통신 방식을 수용하는 시스템들은 항시 전력을 사용하고 있고, 사용자에게 보다 편리하고 많은 서비스를 제공하기 위해서 한 기지국에 모두 설치되어 있는 경우가 일반적이다. 무선데이터의 수요는 시간, 장소 등에 따라서 유동적으로 변화한다. 만약 무선데이터의 수요에 따라서 현재 운용중인 이동통신 시스템들을 상황에 맞게 선택적으로 운용한다면 많은 전력을 절감할 수 있다. 본 논문에는 무선데이터의 수요에 따라서 운용하는 통신시스템에 전력공급을 제어하는 이동통신 인프라의 전력절감을 위한 부하관리 시스템의 설계와 구현에 관해서 기술한다.

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포토닉스 기반 테라헤르츠 무선통신 기술 동향 (Photonics-based Terahertz Wireless Communication)

  • 김현수;이의수;박동우;이일민;문기원;최다혜;신준환;김무건;최경선;박경현
    • 전자통신동향분석
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    • 제34권3호
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    • pp.75-85
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    • 2019
  • The bandwidth of wireless communication is expected to grow exponentially due to the expansion of mobile devices and the increase of real-time and realistic multimedia services. Recently, the studies on terahertz band wireless communication have been actively conducted for the next generation communication after 5G wireless communication. The terahertz band, which is the unallocated frequency band, has been applied to the non-contact, non-destructive quality inspection industry such as the terahertz imaging and spectral systems through the development of terahertz generating and detecting components. This article briefly describes recent research trends on terahertz wireless communication technologies and introduces the details of photonics-based terahertz devices and systems that have been focused on the Terahertz Basic Research Section of Electronics and Telecommunication Research Institute.

철도 무선통신 기술동향 및 국내 운용현황 (The Operation Conditions of Domestic Railway Wireless Communication Network and Those Technical Trends)

  • 김범곤
    • 한국전자통신학회논문지
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    • 제11권4호
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    • pp.379-386
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    • 2016
  • 고속철도를 운영할 뿐 아니라, 고속열차를 생산하는 우리나라는 고속철도를 효율적으로 운용하기 위해 각 분야에서 승차감 향상, 주요부품 자동진단, 차상 전기검측, 소음저감 등 여러 가지 기술을 개발하고 있다. 본 논문은 그 중에서도 철도 무선통신분야의 기술을 이해하기 위해, 유럽과 중국 및 미국의 철도 무선통신시스템의 운용현황을 설명하고, 국내 철도에도 적용될 철도용 LTE 시스템의 기술현황을 소개한다. 아울러 현재 운용하고 있는 국내 철도무선통신망 현황과 4세대 무선통신망에 대한 국가연구개발사업의 개략 및 고속철도 현장에서의 시험계획을 소개한다.

Analysis of Fiber-optic Link Budget for Optically fed Wireless Communication

  • Kim, Jung-Tae
    • Journal of information and communication convergence engineering
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    • 제1권1호
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    • pp.35-38
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    • 2003
  • Analyses of performance of wireless broadband communication systems employing fiber-optic link have presented. We have analyzed CNR penalty to evaluate system performance by taking into account, radio link considering rainfall attenuation, and optical link considering several carrier-to-noise ratio versus the optical modulation index.

RF CMOS 기술을 이용한 이동통신용 부품기술 동향

  • 김천수
    • 한국전자파학회지:전자파기술
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    • 제12권3호
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    • pp.49-59
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    • 2001
  • Wireless communication systems will be one of the biggest drivers of semiconductor products over the next decade. Global Positioning System (GPS) and Blue-tooth, HomeRF, and Wireless-LNA system are just a few of RF-module candidate awaiting integration into next generation mobile phone. Motivated by the growing needs for lowcost and multi-band/multi-function single chip wireless transceivers, CMOS technology has been recognized as a most promising candidate for the implementation of the future wireless communication systems. This paper presents recent developments in RF CMOS technology so far, much of them have been developed in ETRI, and from them forecasts technology trends in the near future.

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RF CMOS 기술의 현재와 미래

  • 김천수;유현규
    • 전자공학회지
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    • 제29권9호
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    • pp.1020-1020
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    • 2002
  • Wireless communication systems will be one of the biggest drivers of semiconductor products over the next decade. Global Positioning System (GPS) and Blue-tooth, HomeRF, and Wireless-LNA system are just a few of RF-module candidate awaiting integration into next generation mobile phone. Motivated by the growing needs for low-cost and multi-band/multi-function single chip wireless transceivers, CMOS technology has been recognized as a most promising candidate for the implementation of the future wireless communication systems. This paper presents recent developments in RF CMOS technology, which is classified into device technology and circuit technology and from them forecasts technology trends in the near future.

RF CMOS 기술의 현재와 미래

  • 김천수;유현규
    • 전자공학회지
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    • 제29권9호
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    • pp.18-30
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    • 2002
  • Wireless communication systems will be one of the biggest drivers of semiconductor products over the next decade. Global Positioning System (GPS) and Blue-tooth, HomeRF, and Wireless-LNA system are just a few of RF-module candidate awaiting integration into next generation mobile phone. Motivated by the generation mobile phone. Motivated by the growing needs for low-cost and multi-band/multi-function single chip wireless transceivers, CMOS technology has been recognized as a most promising candidate for the implementation of the future wireless communication systems. This paper presents recent developments in RF CMOS technology, which is classified into device technology and circuit technology and from them forecasts technology and from them forecasts technology trends in the near future.

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