Fibre-optic network will check for oil pipeline leaks

Optasense is to install 200 of its Distributed Acoustic Sensing systems in the Middle East over the next two years

A UK company that converts fibre-optic communications cabling into thousands of acoustic sensors, able to detect events such as leaks in pipelines or incursions on borders, has sealed a landmark deal to monitor 8,000km of assets in the Middle East.

Optasense, a wholly-owned subsidiary of defence firm Qinetiq, is to install 200 of its Distributed Acoustic Sensing systems in the region over the next two years to monitor oil and gas pipelines, refineries, airports and other critical national infrastructure.

The system fires a laser 10,000 times a second from ‘interrogator’ units installed up to 50km apart. The interrogators then detect the Rayleigh backscatter from the pulses. Rayleigh backscatter is a naturally occurring phenomenon sensitive to vibration, which in this case results from imperfections in the fibre-optic cable. The system analyses the backscatter signal for disturbances using algorithms originally developed to analyse sonar in defence applications.

The Optasense system effectively creates thousands of ‘virtual microphones’, up to 5,000 channels over a 50km stretch of cable, able to detect, locate and classify activity from vibrations.

Magnus McEwen-King, managing director of Optasense, said: “We turn the existing fibre for communications into a nervous system, dramatically reducing the costs associated with the sensor network and making much better use of the fibre and the organisation’s response mechanism.

“It’s not that we can make fibre listen. We’ve got the brain that can interpret it and provide realtime data, developed from decades of research into sonar signal processing from Qinetiq."