Elektronik Lab, one of India's largest distributors of marine communication and navigation equipment, is proud to announce the deployment of the Sonardyne Tsunami Detection System in the Bay of Bengal by the National Insitute of Ocean Technology on February 15, 2007 at 17.30 hours.
Developed following the devasting effects of the 2004 Indian Ocean tsunami, the Sonardyne system can be deployed on the seabed in the deep ocean from where it will monitor the pressure of the water above it. A tsunami wave in deep water creates a small but measurable change in pressure that will be maintained for as long as twenty minutes. By monitoring any such changes caused by a tsunami, the detection system will trigger an alarm that sends an acoustic warning message to a buoy-mounted transceiver on the surface. The transceiver, in turn, relays the message via a satellite data link to a control centre onshore.
The Tsunami Detection System system from Sonardyne is based upon a Compatt 5 subsea transponder that uses the latest Wideband acoustic signal technology to provide robust through water communications in deep water. Compatt 5s are used extensively in the oil and gas industry where their reliability and performance is regularly trusted for use on the most complex subsea construction survey projects.
The advantage in using Sonardyne’s system over those of other suppliers is that the system is a single compact unit. The Compatt 5, which has been time tested for reliable communications in water depths of up to 7,000 meters, comprises a high accuracy pressure sensor, battery, transducer, acoustic release and data logger. This compact design has helped in effectively removing the weak link of cables and connectors in underwater equipment. The floatation collar, which fits around the Compatt 5, gives the system the required buoyancy to keep it upright at all times, and enables it to recovered to the surface whenever the release command is given.
The new intelligent Wideband technology has been used to increase the efficiency of communication and reduce power consumption, which is a major factor for this type of system. This make it possible for the Compatt 5 to remain in continuous monitoring mode on the seabed for up to four years.
On the surface, a transceiver is connected to the buoy to receive hourly reports from the Compatt on the seabed. The system goes into the Tsunami warning mode as soon as the seabed system detects changes in pressure readings. On receiving this alert message, the THRANE & THRANE INMARSAT C terminal, which is housed in the buoy for onward communication to the shore, helps to establish a reliable link with NIOT Shore Station and ensure that the vital data is transferred.
The Sonardyne Detection System underwent stringent testing at the acoustic tank facility at NIOT, Chennai. Nick Street from Sonardyne’s headquarters facility in the UK and Rangarajan from Elektronik Lab accompanied the NIOT team during the successful launch of the system.