MAIN Wireless on ships Page 6 I think DECK Wireless communications have tremendous applications on ships, both in talking to

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Wireless on ships

Page 6 I think


Wireless communications have tremendous applications on ships, both in talking to
the shore and talking on the ship itself

Digital Ship November
mobile data
wireless networks.doc

m working on it


As everybody knows, wireless data communications is widely touted as the next big
thing, and enormous sums of money are being thrown at developing technologies.
Some of these will prove very helpful onboard ships.

Probably the most

important is Bluetooth, developed by technology company
Ericsson, which enables electronic devices up to 100m apart to communicate data
with each other at rates of up to 1 Mb per second. This could be used for seafarers or
cruise passengers to talk to one

another on the ship using cellular phone
type devices.
They could also retrieve data from the database onto Palm Pilot
type devices.

Technology company AvantGo has developed a range of solutions to today’s
compatibility and device interconnection proble
ms. By supporting a wide range of
network protocols and wireless devices from a central server, information can be
accessed where its needed using whatever is at hand, whether phone, palmtop or PC.

The developments in mobile communications will also lead

to benefits in the ship to
shore communication itself. New communication protocols are reducing the price of
satellite communication and optimised messaging systems can reduce the amount of
data that needs to be sent. All these developments mean that app
lications using ship
shore data connections could be more powerful and more viable than ever.

By combining onboard radio communication networks with the ship
shore satellite
communications, it is possible to do a great deal more. For example, seafarers co
make calls home from any private location on the ship, using cellular phone

By supporting all the protocols, as with AvantGo, or introducing a device wide new
one, as with Bluetooth, mobiles, palmtops and PCs can be integrated together,

communicating to the rest of the world via whatever global network is available.


Things we can do onboard ships

With wireless networks onboard, ships can be integrated into a company’s shore
based data management system. Data can be synchroni
sed between the ship and the
based office, meaning users will not have to worry about multiple copies of

The data stored in the central ship’s office can then be distributed around the vessel,
using a wireless data network, so it can be perus
ed anywhere on the vessel. For
instance, an engineer conducting maintenance of engines onboard can download
performance data from the engine by connecting a mobile device such as a Palm Pilot
through a wireless link.

By connecting to the ship’s network,

the data can be compared with a record of
previous data readings from that engine. Thus any changes can be that may lead to
faults or failure can be analysed.

If there is any cause for concern, the data can be sent straight to the engine

website, where the problem can be diagnosed by comparing the
readings to other engines of the same model. Thus the problem can be quickly
diagnosed and the engineer can get to work.

If any replacement parts are needed, they can be ordered immediately us
ing the same
Palm Pilot, by browsing through an offline catalogue or entering a request through the
company’s electronic order system.



Bluetooth is an initiative to replace ca
ble connections with a wireless data link. The
system uses a small radio transmitter that is incorporated into a mobile device such a
GSM phone, a laptop or palmtop. Within a range of between 10 and 100 meters
depending on the application, devices can ta
lk to each other and with a network

A Bluetooth system would prove very helpful for communications between people
and devices actually onboard the ship itself. For example, seafarers and cruise ship
passengers could make phone calls to each other
onboard, using devices similar to
cellular telephone calls. The phone call could easily be channelled to land over
Inmarsat, so that they can make calls home from any private location on the ship.

Equipment monitoring could be as simple as simply walking

into the engine room
with a palmtop; every piece of equipment could be fitted with a Bluetooth transmitter
and all the performance data could be downloaded to the operator as he or she walks
around, without the need to manually connect to an interface.

t is one of the design principles that the Bluetooth module should be cheap enough to
install even in devices such as mice and keyboards. Eventually the cost is likely to be
as low as $5.

Bluetooth is designed to be very easy to use. It requires no user

interaction, with the
communication link being established automatically between any two devices in



AvantGo is a technology provider that develops infrastructure for conne
cting mobile
devices to a central network server. Users can access information using a variety of
different devices without having to worry about the specific protocol that needs to be
used in each case.

The system simplifies administration and informa
tion management. Data downloaded
onto devices can be synchronised with the main server either online, or by making
new entries offline and waiting for the next time the user connects to the network.
Thus within a local network, AvantGo consolidates the i
nformation available and
simplifies its delivery to mobile devices.

Data can be distributed via any network, facilitating data access. Thus any device,
including handheld, wireless handheld or internet
enabled phones can be used via
direct connections, d
irect dial, wireless networks or the internet.

Content from third party service providers is delivered through the AvantGo server,
which communicates with wireless devices via the internet.

One of the major advantages is the ease with which businesses
can get their web
services out onto the AvantGo network and onto mobile users. In the simplest case,
freely downloadable HTML code from the AvantGo website will create an AvantGo
‘channel’ that delivers content to the entire network of over 1 million user

The benefit for enterprise users is the ability to extend existing interfaces to enable
employees to access data with mobile devices. This can lead to faster information
distribution, reduced communications costs and increased accuracy of data.


Mobile mail

OnAir Mobile is part of a wireless messaging initiative by Inmarsat and is being
developed by Telesis North. The system is designed specifically for the needs of
mobile users over expe
nsive, low bandwidth connections, such as seafarers.

Rather than dialling in to a mailbox in order to find out if there are any messages
there, which often means a wasted call, users can be positively notified when there are
messages waiting. Communicat
ion is optimised for a variety of networks including
GSM, satellite, and digital radio, with special independent protocols developed for the
Inmarsat network.

Compression is used to minimise the data that needs to be sent, and messages are
batched toget
her when possible so that the effect of the ‘handshake’, when the
connection is established, is reduced.

The system is based upon Microsoft Exchange server, used by 60 per cent of ships
which have e
mail onboard, and the Outlook mail client. This means t
hat the majority
of users will be able to continue using their existing mail programme.

Telesis North is releasing a full development kit to encourage partners and customers
to contribute to OnAir by generating new products and applications.


nmarsat Packet Data Service

The Inmarsat Packet Data Service (IPDS), expected around 2002, will herald a new
generation of communications over satellite. The main benefit is that under IPDS,
no longer have to pay by the minute; they can pay by the number of data bits
they send.

This means that using the satellite connection to send irregular lumps of data is much
more viable. So for example applications such as remote sensing or telemetry, w
send small packets of data at regular intervals, can benefit from reduce costs.

Other viable applications will include the transmission of e
mail, browsing ‘lite’ web
sites and the transfer of small files.

The IPDS system increases the capacity of t
he Inmarsat network, because users can
share a communications channel. This is in contrast to the current circuit switched
network, where if a user opens a 64kbit/s channel, then they get the whole of that
channel to themselves even if they are not using
it fully, and they pay for it!

With IPDS the channel capacity can be utilised more efficiently by allowing any free
bandwidth to be taken by another user.

Quality of service is central to the IPDS proposal. This is an important issue, because
there must

be a way of deciding which users get the bandwidth if the channel is busy.
In the standard release, it works on a ‘best effort’ approach; if the bandwidth is there
you can have it. For users with special requirements, it will be possible in the future
o obtain a constant bit rate service.

Imhotek has been testing the IPDS service release on a wide range of applications and
comparing its performance with other networks. The average speed was found to be
somewhere mid
way between the 9.6 kbps of Inmarsat
B (normal) and the 64 kbps of
Inmarsat B High Speed Data.