The maritime VSAT system is a shipborne wireless communication system that uses communication satellites as relay stations. It has significant advantages such as global (excluding the polar regions), all-weather, stable, reliable, high-quality, large-capacity, and automatic communication. It can improve ship operations and increase management efficiency, closely link ships and shores, and is helpful in safeguarding human life at sea.
The maritime VSAT system (system of maritime satellite communications) is a shipborne wireless communication system that uses communication satellites as relay stations. Its characteristics include high quality, large capacity, and global, all-weather, and all-time communication. In 1976, the United States launched three maritime communication satellites over the Atlantic, Pacific, and Indian Oceans, establishing the first maritime satellite communication station in the world, primarily serving the navy. The International Maritime Satellite Organization was established in July 1979, and the International Maritime VSAT System was established in 1982, becoming the first generation of international maritime VSAT systems. Although the maritime VSAT system is expensive, it has many advantages and broad prospects for development.
The maritime VSAT system consists of three major parts: communication satellites, shore stations, and ship stations.
It is the system's relay station used to receive and transmit signals from shore and ship stations. Satellites are deployed in the Pacific, Atlantic, and Indian Ocean regions, using geostationary orbit satellites, and providing telephone, telegraph, fax, and shared calling services.
It is a maritime satellite communication earth station located on the coast, responsible for controlling the communication network. It is equipped with antennas and other equipment, and can be connected to other communication networks on land.
It is a maritime satellite communication earth station installed on the ship, which is the communication terminal of the system. It is equipped with parabolic antenna and other equipment, and telephone communication uses frequency modulation, while telegraph communication uses phase-shift keying modulation. The allocation of communication capacity for each communication satellite is responsible for assigning network coordination stations for the allocation of satellite communication channels. Telegraph channels are pre-assigned to each shore station, which is responsible for allocating time slots for telegraph communication with ship stations. Telephone channels are controlled by the network coordination station and allocated after application by ship and shore stations.