• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.237-253
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• 2019

For massive multiple-input multiple-output (MIMO) circumstances with time division duplex (TDD) protocol, pilot contamination becomes one of main system performance bottlenecks. This paper proposes an uplink pilot sequence assignment to alleviate this problem for spatially correlated massive MIMO circumstances. Firstly, a single-cell TDD massive MIMO model with multiple terminals in the cell is established. Then a spatial correlation between two channel response vectors is established by the large-scale fading variables and the angle of arrival (AOA) span with an infinite number of base station (BS) antennas. With this spatially correlated channel model, the expression for the achievable system capacity is derived. To optimize the achievable system capacity, a problem regarding uplink pilot assignment is proposed. In view of the exponential complexity of the exhaustive search approach, a pilot assignment algorithm corresponding to the distinct channel AOA intervals is proposed to approach the optimization solution. In addition, simulation results prove that the main pilot assignment algorithm in this paper can obtain a noticeable performance gain with limited BS antennas.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 추계종합학술대회
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• pp.841-844
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• 2005

다양한 이동 기술, 센서, 원격 제어 및 인프라가 발달하고 생활의 질에 대한 기대치가 높아짐에 따라 홈 네트워크에 관한 다양한 기술과 서비스에 관한 연구과 개발이 진행되고 있다. 현재까지는 사용자에게 높은 수준의 홈 네트워크 서비스 개발에 중점을 둔 반면에, 이의 안전성을 보장하는 홈 네트워크 보안에 관해서는 많은 연구가 이루어지지 않고 있는 실정이다. 따라서 본 논문에서는 다양한 사용자가 각자의 특성과 취향에 맞는 홈 네트워크 서비스를 제공받을 수 있고, 외부의 불법 접근이나 침입으로부터 홈 네트워크 시스템을 안전하게 보호하기 위한 홈 네트워크 접근 모델을 제안하고자 한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.733-736
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• 2006

다양한 이동 통신 기술, 센서, 원격 제어 및 네트워크 인프라가 발달하고 생활의 질에 대한 기대치가 높아짐에 따라 홈네트워크에 관한 다양한 기술과 서비스에 관한 연구와 개발이 활발히 진행되고 있다. 홈네트워크 기술은 아직까지는 초기 투자 단계로서 사용자에게 필요한 서비스를 개발하고 편리성을 증대시키는 방향으로 개발되고 있지만, 더욱 서비스가 활성화되면 편리성을 보장할 수 있는 안전성에 관한 연구가 병행되어야 할 것이다. 따라서 본 논문에서는 내/외부의 불법 접근 및 허가되지 않은 접근으로부터 홈네트워크 시스템을 안전하게 방어하고 보호하기 위한 접근 제어 메커니즘을 제안한다.

• 산업공학
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• 제9권3호
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• pp.1-9
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• 1996

Competition in telecommunications field brings about change in attitudes toward technology development. It is no longer the case that technology development itself has merits but that technology development should be considered in terms of its economic concepts such as the cost-effectiveness concept. Techno-Economic study intend to incorporate the idea of economic efficiency into technology development and management so that economic potential of technologies is maximized. This paper categorizes the contents of techno-economic study in telecommunications and information technologies and suggests a framework of techno-economic study based on technology lifecycle and decision makers.

• 전자통신동향분석
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• 제35권7호
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• pp.23-35
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• 2020

In this paper, we introduce ETRI AI Strategy #3, "Leading Future Technologies of Network, Media, and Content." Its first goal is "to innovate AI service technology to overcome the current limitations of AI technologies." Artificial intelligence (AI) services, such as self-driving cars and robots, are combinations of computing, network, AI algorithms, and other technologies. To develop AI services, we need to develop different types of network, media coding, and content creation technologies. Moreover, AI technologies are adopted in ICT technologies. Self-planning and self-managing networks and automatic content creation technologies using AI are being developed. This paper introduces the two directions of ETRI's ICT technology development plan for AI: ICT for AI and ICT by AI. The area of ICT for AI has only recently begun to develop. ETRI, the ICT leader, hopes to have opportunities for leadership in the second wave of AI services.

• 전자통신동향분석
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• 제35권6호
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• pp.88-96
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• 2020

As the usability and value of personal information increase, the importance of privacy protection has increased. In Korea, the scope of the use of pseudonymized personal information has increased because of revisions to the law. In the past, security technologies were used to safely store and manage personal information, but now, security technologies focused on usability are needed to safely use personal information. In this paper, we look at issues related to the de-identification and re-identification of personal information. Moreover, we examine the standards and techniques related to the de-identification of personal information.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1320-1323
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• 2002

This paper reviews the Korean government’s selection process of core wireless communications technologies, and presents technology trends, perspectives and strategies of 5 core technologies to develop in wireless communications areas based on the mid term IT technology development plan(2002∼2004). Delphi Panel Method and Analytic Hierarchy Process(AHP) Analysis were adapted to select 30 core technologies in 9 strategic areas. Especially, 5 core wireless communications technologies out of 24 required technologies are selected: 4 G Core Technology, Broadband Wireless Access Network Technology, IMT-2000 Plus STP Technology, OBP Based Multimedia Satellite Communications Technology, Stratosphere Communications System Technology. Strategic national IT R&D program has been essential to continue success story of CDMA technology, and acquiring technology independency from advanced nations. In long term perspectives, a strategy of intensive investment with prudent selection onto core technologies should be deployed in the IT R&D programs. Also, the national IT R&D programs should be limited in the high risk & high returen areas where only government can afford the failures as well as better spill over effects are expected for the technology development and national economy. Korean industry has some strength in wireless communications technology area. Therefore, more policy concerns should be given into this area not only to secure present strength but also to explore better technology competitiveness.

• Journal of Communications and Networks
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• 제7권2호
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• pp.135-143
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• 2005

This paper presents an investigation of satellite radio access technology for beyond IMT-2000 systems. Although we could not see any active role of a satellite system in the 3G networks, satellite system will provide strong advantages in future systems for certain applications. Because a satellite link has longer round trip delay than a terrestrial link, we need technologies that would make the satellite component especially efficient. After presenting the satellite radio interface of the 3G system, we suggest several points which need to be considered in the beyond 3G systems. We also suggest a few candidate technologies with various simulation results.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.839-842
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• 2005

다양한 이동 기술, 센서 기술 및 원격 제어 기술이 발달하고 생활의 질이 향상됨에 따라, 홈 네트워크에 관한 연구와 개발이 활발히 진행되고 있다. 현재 네트워크 서비스 사업자와 건설 업체를 중심으로 다양한 홈 네트워크 서비스를 제공하려는 노력이 진행되고는 있지만 안전하고 효율적인 보안서비스를 제공하기에는 아직 미흡한 측면이 있다. 따라서 본 논문에서는 홈 네트워크 서비스를 제공하는데 있어서 안전하고 다양한 사용자 인증 메커니즘을 제공하고 효율적으로 서비스를 제어하기 위한 보안 프레임워크를 제안한다. 즉, 각 호마다 설치되어 동작하는 홈 게이트웨이를 기반으로 호별 보안 정책을 설정하고 수행함으로써 다양한 보안 시나리오를 가능하게 하며, 추후 사업자 서버 및 로컬 서버와의 연동을 통해서 능동적인 홈 네트워크 시스템 보안 서비스를 제공하고자 한다.

• 전자통신동향분석
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• 제35권4호
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• pp.21-33
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• 2020

Single photon detector technologies have emerged as powerful tools in optical quantum information applications such as quantum communication, quantum information, and integrated quantum photonics. Owing to significant attempts in the previous decade at improving photon-counting detectors, several single photon detectors with high efficiency and low noise have been realized within the optical wavelength regime. In this paper, we provide an overview of current studies on single photon detectors operating at wavelengths from the ultraviolet to the infrared. In addition, we discuss applications of single photon detector technologies in quantum communication and integrated quantum photonics.