• Title/Summary/Keyword: Space Communications

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차세대 무선통신에서 용량 증대를 위한 Space-Time 부호화 기법

  • 김영주;이황수
    • Information and Communications Magazine
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    • v.18 no.6
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    • pp.119-125
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    • 2001
  • 1990년 초반부터 송신 다이버시티에 대한 연구가 있어 왔다. 1990년 후반부터는 송수신 다이버시티에 대한 실용적인 결과가 부호 이론과 접목이 되면서 나오기 시작한다. 그 중에서 매우 유용한 결과인 Space-Time 부호에 대하여 다룬다. 본 논문에서는 직교 Space-Time block code. Layered Space-Time processing, 그리고 Space-Time trellis Coding의 세 가지로 분류하여 내용을 정리한다.

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Link Scenario Design and Performance Analysis for Korean Lunar Explorations (한국형 달 탐사를 위한 링크 시나리오 설계 및 성능분석)

  • Jeong, Jinwoo;Oh, Janghoon;Yoon, Dongweon;Kim, Sang Goo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.4
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    • pp.212-214
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    • 2014
  • In this paper, we present the scenario designs of the possibility of space communications for Korean Lunar Explorer and the analysis of its performance, depending upon the explorer's position within the moon's orbit after being launched from earth. As per each scenario, we would like to propose the analysis of the possible communication times and total transmission throughput data per day in two cases: one for using DSN and another for using only Korean's ground station.

Adaptive Channel-Matched Extended Alamouti Space-Time Code Exploiting Partial Feedback

  • Badic, Biljana;Rupp, Markus;Weinrichter, Hans
    • ETRI Journal
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    • v.26 no.5
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    • pp.443-451
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    • 2004
  • Since the publication of Alamouti's famous space-time block code, various quasi-orthogonal space-time block codes (QSTBC) for multi-input multi-output (MIMO) fading channels for more than two transmit antennas have been proposed. It has been shown that these codes cannot achieve full diversity at full rate. In this paper, we present a simple feedback scheme for rich scattering (flat Rayleigh fading) MIMO channels that improves the coding gain and diversity of a QSTBC for 2$^n$ (n=3, 4, ${\cdots}$) transmit antennas. The relevant channel state information is sent back from the receiver to the transmitter quantized to one or two bits per code block. In this way, signal transmission with an improved coding gain and diversity near to the maximum diversity order is achieved. Such high diversity can be exploited with either a maximum-likelihood receiver or low-complexity zero-forcing receiver.

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통우연 소식

  • The Korea Society of Space Technology
    • Satellite Communications and Space Industry
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    • v.2 no.1
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    • pp.160-161
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    • 1994
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