• Title/Summary/Keyword: half-duplex

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Analysis and Proposal of Communication System for Maritime HF Band Digital Data Exchange (해상 HF대역 디지털 데이터 교환을 위한 통신시스템 분석 및 제안)

  • Choi, Sung-Cheol;So, Ji-Eun;Park, Hyung-Chul
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.12
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    • pp.2249-2260
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    • 2017
  • IMO (International Maritime Organization) has been providing GMDSS (Global Maritime Distress and Safety System) and mandating to install distress and safety systems according to SOLAS. Digital-HF(High-Frequency) coast station communication system maintains interoperability between ship and coast station and digital data exchange in maritime mobile service by digitizing existing analog base voice communication. In this paper, we analyze ITU-R M. 1798-1 established by ITU for digital HF communications and propose Advanced annex2 and new Annex 5 to improve the problems of the existing Annex 2 and Annex 4. The proposed OFDM protocol basically adopts ARQ (Automatic Retransmission Request) which retransmits when an error occurs in a half-duplex manner between an information transmitting side (ISS) and an information receiving side (IRS) and we propose a digital HF communication system and its operational concept which is more reliable and superior than the existing ITU-R M. 1798 by implementing technical development on implementation and performance improvement.