Marine satellite communication system performance and application near the system operational boundaries

Discusses how recognizing the importance of detailed assessment of INMARSAT capabilities for supporting alerting needs throughout the World, the USSR administration has carried out, in 1984-1987, a series of tests within the elevation angle range 10° to O°. Involved in the tests were Soviet ships equipped with INMARSAT Standard A ship Earth stations. The test objective was to investigate the effects which are essential for establishing reliable communication channels at low elevation angles. A particular attention was given to the telex channel performance as more susceptible to the influence of disturbances. Results of the investigations are described