MARY ROSE PROJECT

Portsmouth Harbour 2004

This project was undertaken by 2 of our specialist business partners - Networks by Wireless,
and Martin Dawes Marine. The aim was to provide a radio link from the dive exploration site,
to the museum where guests could view the progress 'Live' on flat screen television.


From left to right: Portsmouth Harbour and Spitbank Fort

Firstly there were cameras mounted on the divers' helmets, which were used to transmit
pictures via a wireless link to a receiver that was installed on Spitbank fort.



These pictures were in turn transmitted from the fort, directly to another receiver
mounted on the roof of the Pall Europe building - which towers above the Mary Rose Museum.



Then finally, the pictures were beamed down to another receiver mounted on the side of
the museum, with a normal networking cable providing the link to the flat screen television inside.



Line of sight was a requirement for all of the radio links. The link from Spitbank Fort
was particularly remarkable, as it allowed for the passing of large obstructions - ships in particular.
The link continues to be maintained, due to the signal being re-sent constantly until the object has passed the transmission path.

THE TECHNOLOGY INVOLVED IN THE PROJECT

The radio links were 54 Mbps, 1EEE 802.11(b), using the PROXIM TSUNAMI model,
and transmitting at around 2.4 GHz, in the licence-free industrial scientific and medical wavebands.
An Omnidirectional antenna was used on the diving control vessel. This was due to
the fact that during the salvage operation, the ship moved its position by means of 4
adjustable anchors arranged in a rectangular pattern.
The cameras were using internet protocol, (IP) and were therefore ideal for interfacing
onto a LAN network topology. The use of hubs and category 6 OTP cable ensured that clear,
reliable pictures were broadcast and received over the complete 4.5 km link.
This enabled visitors to view the divers 'Live' at work on the sea bed.