S t a n d a r d - C : Low-Cost Satellite Communications Terminal

The International Maritime Satellite Organization (INMARSAT) has developed specifications for a new lower-cost, very small satcom system that will, for the first time, bring the benefits of satellite communications within the reach of all sizes and types of vessels.

The Standard-C concept received an important boost in April, when the International Maritime Organization (IMO) agreed to accept Standard- C to satisfy the basic communications requirements of the Future Global Maritime Distress and Safety System (FGMDSS) for all ships of 300 grt and over operating within the coverage areas of INMARSAT satellites.

Unlike the normal Standard A terminal, which provides full duplex telephone and telex service, Standard C will be teletype only. So far, only prototypes have been shown, but INMARSAT expects manufacturers to be offering production models very quickly. The prototype was built at INMARSAT from readily available components. It measures 12 X 8.5 X 5 inches and weighs only 13 pounds, excluding the battery pack or main supply unit. It may be estimated that when produced in volume for the commercial market, Standard-C terminals will be significantly smaller, lighter and more power efficient than the prototype.

To minimize final costs still further, Standard-C will be able to operate using a small, omnidirectional, non-stablilized antenna and may form part of a single unit containing all of the microwave and signal processing electronics. The unit could be mounted high on the vessel, giving it a clear, unobstructed view of the horizon, like a VHF antenna. It could be connected to the data terminal equipment below decks through a single cable providing the interface and power.

The choice of data terminal equipment may range from a simple keyboard entry and display device to a microcomputer system capable of preparing and displaying received messages and monitoring and controlling the numerous other functions on the vessel. INMARSAT says that production models will probably cost no more than $5,000.

The Standard-C system provides data transmission between the ship and coast earth stations and vice versa, at an information rate of 600 bits per second. At the coast earth station, all messages received from the ship or terrestrial subscriber will be routed through a storeand- forward message switch. This may, in turn, provide access to and from a variety of telecommunications services, such as telex, teletex, voice-band data, packet switched data networks and elapsed lines.

Standard-C will therefore be able to access virtually any telecommunications service with the exception of telephone, according to INMARSAT.

In addition to international telex, the potential to access such a wide variety of communication services will make possible all types of data services, such as electronic mail and public data banks, through voiceband data networks or packet switched data networks and exchange computer files between compatible systems on board and ashore. It may also be used for monitoring data collection and for control purposes where totally automatic operation may be desirable.

Standard-C, says INMARSAT, may become the "workhorse of marine communications" in the 21st century, just as Morse key was in the past.

For further information, C i r c l e 4 9 on Reader S e r v i c e Card

Maritime Reporter Magazine, page 32,  Jul 15, 1986

Read S t a n d a r d - C : Low-Cost Satellite Communications Terminal in Pdf, Flash or Html5 edition of July 15, 1986 Maritime Reporter

Other stories from July 15, 1986 issue


Maritime Reporter

First published in 1881 Maritime Reporter is the world's largest audited circulation publication serving the global maritime industry.