Air and sea rescue via satellite systems: Even experimental systems have helped survivors of air and sea accidents. Two different approaches are discussed

Abstract

The Cospas-Sarsat project aims to develop a scheme in which a small battery-powered transmitter on a ship or aircraft would be activated, manually or automatically, in an accident. Once activated, the transmitter, or beacon, would emit a low-power omnidirectional signal that would be picked up by a satellite. The satellite would relay the distress signal to an earth station, which in turn would send the message over conventional communication lines to a rescue center. Concurrently with development work on this project, and experiment with high-orbit geostationary search-and-rescue satellites is in progress. The geostationary experiment is aimed exclusively at the commercial maritime industry and is considering only the technical aspects of the beacon-to-satellite and satellite-to-earth links under uniform, controlled conditions. This program is using satellites and earth stations of Inmarsat, the 31-nation consortium that offers satellite communication services to merchant ships and offshore oil rigs.