• Title/Summary/Keyword: radio telex

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A Study of the Hangul Codes and Algorithm for the NBDP System (NBDP시스템의 한글코드 및 처리 알고리즘 연구)

  • 유형열;조형래;김기문
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.1 no.1
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    • pp.113-121
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    • 1997
  • The maritime mobile communication system has been changing to the new system that is facilitated by the radio telex, digital selective calling and maritime satellite communications from the old system by the radio telegraphy and telephone according to the GMDSS. The NBDP using the ITA No.2 code is a useful media in the maritime communications and provides the procedures of telex. Also it can provide the efficient and more useful functions and the solutions for the incremental traffic requirements by adopting the Hangul code. So, in this paper, we proposed the new Korean NBDP code for the ITA No.2 code, designed and implemented the algorithm which is the processing of the Hangul NBDP code using the microprocessor.

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The study on the trend analysis and countermeasures on the maritime mobile communication (해상이동통신에 대한 국제적 동향 분석 및 대응방안)

  • Song, Jong-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.05a
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    • pp.297-300
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    • 2012
  • Since the adoption of GMDSS, the band 495-505 kHz has no longer been globally used for maritime calling and distress and the designation of this band for calling and distress was suppressed at WRC-07. In accordance with provision RR, maritime mobile operations are presently limited to radiotelegraphy. Accordingly, use of the band has diminished.This frequency band 415 kHz to 526.5 kHz and high frequencies is ideally suited to broadcast from shore to ship. The surface wave propagation of a coast station using this band can provide a coverage area from the coast to 400 nautical miles off shore.

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A Study on the Recent Trends and Prospects of Maritime Satellite Communication Systems (해사위성통신시스템의 현황과 전망)

  • 조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.2 no.1
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    • pp.20-28
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    • 1977
  • The shipping business which consistutes main stream of foreign trades in the world desires more larger and higher speed ships to convey a large amount of cargo at a time rapidly and safely. They also want to introduce new techniques into transportation system so to meet the rapid growing demand of maritime mobile communications with the improvement of efficiency of radio apparatus and reduction of the hard labors of radio operators mechanization and modernization of radio apparatus is necessary. Now HF band is used mainly for communications between maritime mobile stations and coast stations but the quality of received signal is not so good and the coverage is not sufficient by the condition of propagation of waves. There is also limitation of channel capacity in HF band. So to cope with or improve of these defects and meet the demands of modern maritime communication it is essential to introduce maritime satellite communication system in this field. By using the maritime satellite we can establish high quality communication circuits as maritime Telex, Faximile, high speed data transmission line and can expand coverages. Therefore industrial rationalization of marine transportation is possible with the reduction of painful labors of radio operators by improving safety and promoting of efficiency of movement of ships and freights. Obviously it is prospected that the introduction of maritime satellite communication system will bring a rapid promotion of its usuage in maritime mobile communication field and also anticipated that maritime satellite communication system will be a main current in maritime mobile communication field over the world in the near future with moderated cost of transmission links as in the case of INTELSAT in the past 10 years after its first launching.

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