Anti-terrorist diver detection system offers early alert
against threat

QinetiQ's high performance swimmer detection sonar system, Cerberus, has demonstrated unprecedented detection ranges, allowing users time to respond to underwater threats. In recent trials in the UK, Cerberus was able to detect a diver at 900 metres in water only ten metres deep, an improvement on previous detection ranges. This extended range is achieved by exploiting advanced wideband technologies and corresponds to about 30 minutes warning before a diver swimming at one knot reaches their target, allowing operators time to decide on an appropriate response to the threat.

Civilian and military operators are increasingly concerned about the underwater threat to high value maritime assets and incidents in recent years have highlighted the vulnerabilities of ships and coastal sites to attacks of this nature. In March 2004 Hamas frogmen attacked an Israeli beachfront guardpost from the sea and in April 2004 oil rigs off the Iraqi coast were targeted by a number of small boats. The US Navy suffered the loss of 17 sailors when the USS Cole was attacked in Yemen in October 2000 and the Sri Lankan Navy lost a number of vessels in 1995 when Tamil Tigers used suicide divers to attack ships.

Following successful customer demonstrations earlier through 2004 at its Bincleaves site in Dorset, UK, QinetiQ has received further interest from around the world and is currently undergoing an extensive evaluation by the US Navy. The system has already proved effective in tropical waters after an evaluation trial in the Far East in 2003.

Chris Minto, QinetiQ's Cerberus sales manager, welcoming the recent performance enhancement, said: "Cerberus' detection ranges were already world class. By now extending our range and offering customers more time to decide on an appropriate response to underwater threats we have strengthened our position. We are confident that Cerberus represents a potentially life-saving tool in the fight against terrorism and that it could bring great benefit to customers around the world.�

Cerberus can be deployed as a single unit to provide 360° cover for ship protection by being slung from the side of the vessel. Alternatively, a number of units can be attached to the seabed in a cordon to provide harbour security and channel protection. Deployed in this manner, the detection range is extended to one kilometre and beyond.

The main technical challenge in safeguarding ships and harbours from such threats has been the difficulty in locating a human diver because of the lack of a strong sonar target return. Extremely limited underwater visibility greatly reduces the effect of underwater surveillance techniques relying on cameras operating in the visible band. Cerberus' detection capability represents a significant step forward in tackling this challenge.

Target classification is also provided, enabling operators to decide on an appropriate response. The sonar return provided by the target when using Cerberus is detailed enough to allow the identification of distinctive human features at distances approaching 500 metres. The operator can therefore distinguish between the potential terrorist human diver and similar sized mammals (like sealions or dolphins), reducing false alarms.

QinetiQ advocates a layered defence of ports and harbours, designed to protect against a variety of different threats and at different ranges. For this reason, Cerberus and allied QinetiQ technologies, such as long range underwater passive surveillance arrays incorporating our groundbreaking fibre optic sensors (OptaMarine) and high definition surface radar can be integrated to provide a systems solution out to beyond 10km.

To learn more about QinetiQ's technologies visit Stand 72/73 at UDT.