The Problem of Generating False Alert Signals with Help of Digital Selective Calling - DSC in the GMDSS System

In the recently introduced system of Global Maritime Distress and Safety System - GMDSS, the basic and at the same time the only way of sending alert signal with help of terrestrial communication is the digital selective calling - DSC. This system, however, during its seven years period of testing i.e. from 01.02.1992 to 01.02.1999 has caused and still creating many problems and much trouble during its exploitation at sea. One of the most worrying and not clarified problems derives from the generation of false alert signals. Two basic factors may certainly have some influence on the wrong work of the DSC system: • the human factor • interferences resulting from applied solutions of radiocommunication, radionavigation and apparatus systems on seaships In this paper the author wishes to present his exploitation experiences of DSC in real conditions at sea carried out during first phase of introducing the GMDSS system and at the end of the seven years period of its full testing. The obtained results particularly those concerning the problem of generating false alert signals permit to formulate proper conclusions.