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Feature 5 | COMMUNICATIONS SYSTEMS


all via a single terminal. Mobile packet data service (MPDS) capability allows FleetBroadband to provide an ‘always-on’ data connection, enabling data to be transferred as it is generated. In this case, user charges are levied according to the amount of data sent or received rather than time spent on line.


VSAT The very small aperture terminal (VSAT) system can offer four or five times the bandwidth of FleetBroadband using alternative satellites operating in Ku or C bands


Inmarsat has espoused. However, as an Inmarsat spokesman


has argued: “What is the use of having several megabytes of bandwidth if all you do with it is pass e-mails, browse the Internet every now and then, and communicate by voice? Bandwidth has to be paid for, both initially in terms of the equipment, and ongoing for air time. We believe that, by evolving at a pace which matches the needs of the market, we can offer appropriate and affordable solutions that most ship owners will find more than adequate.” Inmarsat also gives shipping accountants


much desired budgetary predictability with a package pricing option. In bringing package pricing to L band, the company has emulated the VSAT community where such arrangements have been established for some time. Under a simple monthly contract, a customer can call on any combination of voice, ISDN or MPDS service up to the ceiling allowed by the contract. Alternatively, users can be charged in the traditional way according to their actual metered usage. One testimonial to FleetBroadband’s


bandwidth capability is the selection of Inmarsat as official satcom provider to entrants in the 2008-9 Volvo Ocean Race, which began in October. The system enables each FleetBroadband FB500-equipped yacht to send regular HDTV (high-definition TV) imagery ashore as well as providing voice and data connectivity including Internet access. Each vessel will have a media representative onboard whose task is to send back footage as crews deal with anything from flat calms to storm-force


58


as distinct from L band, which A selection of Sailor VHF handheld portable VHF radios.


winds and 30m waves. Race organisers estimate that 90GB, equivalent to 20 DVDs, will be sent from boats to race HQ during the round-the-world event. Shipping giant AP Moller-Maersk


recently signed a contract to equip more than 150 vessels with FleetBroadband in a two-year retrofit programme. The order was placed with Inmarsat service provider Marlink, who will supply Thrane &Thrane Sailor 500 terminals across Maersk’s supply service and tanker fleets. Another 150 vessels may follow in a second equipage phase. According to Peter Faurhoej, IT/navigation and communications systems manager for Maersk Supply Services, the new terminals will enable the company to offer its crews Internet access, with all its associated benefits, by the end of 2008, as part of Maersk’s commitment to crew welfare and retention. The multi-million pound order


illustrates the fact that Inmarsat does not supply end users directly. Terminals are provided by equipment partner companies, currently Thrane & Thrane, the Japan Radio Company (JRC) and KVH Industries. T&T’s Sailor 500 cited above, for instance, is the larger of two Fleet terminals produced by the Danish company. With an antenna dome measuring 60cm diameter by 63cm high, the system weighs just 16kg. It provides FleetBroadband IP connectivity at data speeds of up to 432kbit/s, along with ISDN. The smaller Sailor 250 terminal,


recently type approved by Inmarsat, has about half this footprint and delivers data at up to 284kbit/s, with no ISDN. The third element of the supply


triangle is the service/air time provider and satcom integrator, of which Marlink is one example. Others include Satcom Global, Stratos Global Corporation, Vizada Satellite Communications, Telenor Satellite Services, France Telecom Mobile Satellite Communications and Maritime Communications Services, although Inmarsat may revise its distribution framework when contractual arrangements become due for renewal in April 2009.


VSAT alternative Higher-data speed alternatives to Inmarsat take the mariner into the higher-frequency VSAT arena. Although the acronym denotes Very Small Aperture Terminal, the ‘very small’ descriptor is relative, the satcom world having been dominated when the system was named by the huge dishes of land earth stations. VSAT antenna dishes can be up to 4.2m across (although 1m is a common standard for shipborne antennas) and terminals on large ships can weigh around a tonne but, in return, users obtain bandwidths of up to 2MB/s or more per carrier, suitable for providing data-intensive services on dedicated always-on communication channels. (Note, however, that actual bandwidths available to individual users can be somewhat less, depending on


Ship & Boat International November/December 2008


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