• Journal of Astronomy and Space Sciences
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• 제37권2호
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• pp.117-129
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• 2020

In a Satellite communication system, a link budget analysis is the detailed investigation of signal gains and losses moving through a channel from a sender to receiver. It inspects the fading of passed on data signal waves due to the process of spreading or propagation, including transmitter and receiver antenna gains, feeder cables, and related losses. The extent of the proposed tool is to make an effective, efficient, and user-friendly approach to calculate link budget analysis. It is also related to the satellite communication correlation framework by building up a graphical interface link analysis tool utilizing STK^® software with the interface of C# programming. It provides better kinds of graphical display techniques, exporting and importing data files, printing link information, access data, azimuth-elevation-range (AER), and simulation is also possible at once. The components of the link budget analysis tool include transmitter gain, effective isotropic radiated power (EIRP), free space loss, propagation loss, frequency Doppler shift, flux density, link margin, elevation plot, etc. This tool can be useful for amateur users (e.g., CubeSat developers in the universities) or nanosat developers who may not know about the RF communication system of the satellite and the orbital mechanics (e.g., orbit propagators) principle used in the satellite link analysis.

• 한국통신학회논문지
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• 제30권2A호
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• pp.66-79
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• 2005

본 논문에서는 스마트 무인항공기의 데이터 링크의 신뢰성 향상을 위하여 그것을 구성하는 RF 송수신 시스템의 성능 분석 및 통신링크 분석을 수행하였다. 시스템 분석은 데이터 링크의 개발 사양서 및 사용되는 부품의 data sheet를 참조하여 시스템 시뮬레이션 툴인 Agilent EEsof ADS(Advanced Design System)을 이용하여 수행하였고, 통신링크 분석은 스마트 무인항공기 운용 환경에 맞는 다양한 전파 모델들을 이용하여 분석하였다. 그 결과, 시뮬레이션 결과와 개발 사양서에서 나타난 문제점들을 제시하였고, 통신링크 분석을 통해 나타난 문제점 및 시스템 설계를 위한 고려사항에 대하여 제시하였다.

• 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.

• 한국통신학회논문지
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• 제7권4호
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• pp.173-176
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• 1982

通信網에 있어 加人者에 대한 서어비스品質을 표시하는 point-to-point congestion을 single Moment分析法에 의해 구할 때는 link 공급 트래픽의 정확한 계산이 필수적이다. 本論文에서는 종래 link의 全利用度狀態에서 계산되었던 link공급 트래픽이 根定利用度狀態에서 계산되어야 함을 증명하고 그 公式을 유도했다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.249-251
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• 2004

In this paper, we analyses transmission performance of interleaving for cipher communication in TDMA STD DP mode of aerial tactical communication link. In LINK16 link we present about transmission architecture of STD DP mode and study an effect of interleaving, the capability of crypto synchronization pattern, and a quality of degraded effect of transmission communication during crypto communication.

• 한국군사과학기술학회지
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• 제12권2호
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• pp.170-174
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• 2009

This paper describes the wireless communication test environment for the Link-K system and shows the performance analysis of multiple access protocols. The test environment consists of data generator, modem, radio sets, attenuators, and antennas. In case of both CSMA and Roll-Call protocols, throughput performance and delay are measured. And test results are analyzed. The test results would be used for communication performance analysis and network design of Link-K system.

• Journal of Astronomy and Space Sciences
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• 제17권2호
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• pp.257-266
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• 2000

A satellite RF communication link is analyzed based on a simple fundamental equations by systematic approach in this paper. The number of variables related to a design and analysis of satellite RF link is often a dozen or more, thus it is a tedious and time-consuming task. With the given input data, the important parameters are calculated step by step and three communication characteristics such as communication channel capacity, carrier-to-noise ratio(CNR) at the satellite and ground station are analyzed. It gives very useful information to the system engineers for designing and analyzing the overall satellite communication system in the conceptual design phase.

• 한국통신학회논문지
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• 제37권5B호
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• pp.357-364
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• 2012

In Visible Light Communication (VLC) system, with the limitation of transmission range and Field Of View (FOV), LOS (Line of Sight) link between two transceivers should be guaranteed due to the straightness of the visible-light signal. Especially for indoor applications, link recovery is an advantage method to remain the link connection because of the link failure in which caused by movement obstacle. Link recovery schemes try to keep link dynamically without re-initialing connection. This article proposes a new link recover scheme for VLC system by using cooperative communication. Our propose scheme focuses on the QoS reservation resource by GTS in IEEE 802.15.7 specification in which the requested QoS resource from client should be guarantee during the application time. With the link recovery scheme, we will try to continue the link connection as long as possible when unexpected disconnect link. The mathematical analysis and simulation results show that proposed scheme increases the overall reliability of the VLC system.

• 한국항공우주학회지
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• 제33권4호
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• pp.63-70
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• 2005

LINK16은 고수준의 재밍을 갖는 전술네트워크 환경에서 성능 최대화를 위해 설계된 시스템이다. 본 논문에서는 항공통신 전술링크에 사용되는 암호통신에서 동기패턴의 전송성능을 분석하였다. 현재 LINK16 링크에서 운용되는 통신모드(표준 DP, P2SP, P2DP, P4mode)의 전송구조를 고찰하였으며, 암호통신과정에서 주파수간의 충돌확률 및 페이딩 채널에 대한 동기패턴의 영향, 전송성능 열화요인을 분석하였다.

• ETRI Journal
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• 제28권6호
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• pp.815-818
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• 2006

In the global Internet, a constraint-based routing algorithm performs the function of selecting a routing path while satisfying some given constraints rather than selecting the shortest path based on physical topology. It is necessary for constraint-based routing to disseminate and update link state information. The triggering policy of link state updates significantly affects the volume of update traffic and the quality of services (QoS). In this letter, we propose an adaptive triggering policy based on link-usage statistics in order to reduce the volume of link state update traffic without deterioration of QoS. Also, we evaluate the performance of the proposed policy via simulations.