A Study on the Recent Trends and Prospects of Maritime Satellite Communication Systems

해사위성통신시스템의 현황과 전망

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.

世界貿易의 기둥이 되고 있는 海運業界가 大量의 貨物을 安全, 迅速히 運搬하기 위해 船舶의 大型化, 高速化를 꾀하고 있고, 船舶運行에 新技術을 導入하려고 하는 時代를 맞이하여 海事通信도 이의 重要急增에 對處하고 또 無線設備의 使用效率을 提高시킴과 同時에 通信士의 勞苦를 輕減시킬 수 있는 無線設備의 機械化와 近代化가 緊要하다. 船舶通信은 現在 短波通信을 主로 使用하고 있으나 短波는 電波傳播上의 여러 制約에 의해 回線品質이나 通信範圍가 充分치 않고 또 周波數面에서 볼 때 回線容量에 制限을 받고 있다. 이러한 點을 改善하고 多樣化되어 가고 있는 오늘날의 海事通信需要에 對處하기 위해 이 分野에 衛星通信의 導入이 必要하다. 衛星을 利用함에 따라 安定된 高品質의 回線을 設定할 수 있어 텔렉스, 펙시밀리, 高速度通信, 對象海域의 擴大等에 의해 船舶運行管理의 改善, 效率化, 航行의 安全性의 向上을 圖謀할 수 있고 船舶運營의 合理化가 可能하며 通信士의 動勞條件의 改善이 이룩될 수 있다. 海事衛星通信方式의 導入은 過法 10年間 INTELSAT의 경우에서와 같이 점차 回線科의 低廉化에 따라 이의 利用度가 急速히 伸張되어 갈 것이 展望되고 海事衛星通信이 앞으로는 全世界的으로 船舶通信의 主流를 이룰 것이 豫想된다.