Marine Satellite Systems

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Marine Satellite Systems is a company specializing in Vsat, TVRO, Orbit Marine satellite and Marine Direct TV. Here is an informative article explained VSAT.

VSAT is an acronym for Very Small Aperture Terminal . It has a dish Antenna smaller than 3 meters and is a two-way satellite ground station with most antennae being from 75cm to 1.2 meters. It is used to relay data from remote earth station to other terminals or hubs and to do this it accesses satellites in geosynchronous orbit. Most commonly the date it transmits is narrowband such as point of sale transaction used by credit card companies, polling and RFID date or SCADA or broadband data. Also VOIP and Video. It is also very popular for use in marine communications as it lends itself to transportable and mobile usage such as yachts etc. In the 1980’s more than 30,000 antenna systems were sold. These were 6 cms in diameter. The first commercial VSATs were Cband receive-only systems by Equatorial Communications using spread spectrum technology. More than 30,000 60 cm antenna systems were sold in the early 1980s. The Company Equatorial Communications were responsible for the development of a C band (4/6 GHz) 2 way system using 1 m x 0.5 m antennas and sold about 10,000 units in 1984-85. There is also the Ku Band. To provide portable network connectivity for oil field drilling and exploration Schumberger Oilfield and Hughes Aerospace in 1985 co-developed the world’s first Ku Band. Vsats. The vast majority of sites in use today for data and telephone applications are Ku Band VSATs.. The US Postal Service has the largest largest VSAT network (more than 12,000 sites). This was set up by Spacenet and MCI. Wallmart, CVS, Riteaid, Yum Brands, Intralot, Gtech and Sgi are also large VSAT network users in the USA. VSATs are used by car dealerships affiliated with manufacturers such as Ford and General Motors for tranmitting and receiving sales figures and

orders, as well as for receiving internal communications, service bulletins. Distance learning courses and interactive courses also use vsat from manufacturers An Example of this is the FordStar network, used by Ford and its local dealers HughesNet, StarBand, and WildBlue in the United States use VSAT technology for two-waysatellite Internet providers. The Network across Europe is called ASTRA2Connect. Remote rural location which do not have access to less expensive ADSL and Cable internet use Vsat as a means fo delivering broadband internet. There are nearly 650,000 VSAT systems in service and are now based on IP, with a very broad spectrum of applications. As of December 2004[update], the total number of VSATs ordered stood at over 1 million. Annual VSAT service revenues were $3.88 billion. Most VSAT networks are configured in one of these topologies.  To transport data back and forth to each VSAT terminal via satellite a star topology using an uplink site such as network operations center is needed.  It minimizes the need for a centralized uplink site when one uses mesh topology, where each VSAT terminal relays data via satellite to another terminal by acting as a hub.  Some VSAT networks are configured by having several centralized uplink sites (and VSAT terminals stemming from it) connected in a multi-star topology with each star (and each terminal in each star) connected to each other in a mesh topology. This uses a combination of both star and mesh topologies. Where each terminal is acting as a central hub this results in only a single star topology and will sometimes will have each terminal connected to each other as well, resulting in each terminal acting as a central hub. To minimize the overall cost of the network these configurations are utilized. Also to alleviate the amount of data that has to be relayed through a central uplink site (or sites) of a star or multi-star network.

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