Distributed Acoustic Sensing – DAS

Distributed Acoustic Sensing, or DAS, is a way to listen to what is going on far away. It is a sensing system that can hear if something is not right – if your pipeline is leaking or if intruders are trying to enter your facility. Unlike traditional sensor systems, DAS systems have a better range, a higher sensitivity, give you continuous monitoring, and are immune to harsh environments.

Optical fibers are passive sensors

Distributed Acoustic Sensing is a sensing system based on light. An optical fiber replaces traditional discrete sensors and lets you measure sound along with its entire length.

The sensor is a standard, unmodified telecom fiber and has many advantages: Fibers are easy to install, they enable measurements of thousands of locations, they cover a large geographical range, they are immune to electromagnetic interference, they do not carry any electrical power, and they are highly reliable and cost-efficient.

Install the fiber where you want to supervise, e.g., a fence, and it will pick up any acoustic disturbance. Or you may even have access to pre-installed unused telecom fibers (dark fibers), eliminating the need for new fiber installations.

It works over long distances and large areas, without any disruption, and sends responses in real-time.

Ultra-precise detection gives you the exact position

DAS systems are based on interferometric sensing. An ultra-stable, low-noise laser – such as our Koheras lasers – is built into an interrogator that sends light into the fiber and detects the backscattered light.

Complex algorithms analyze what is going on along the fiber, with high precision.

The interpretation software detects every incident but ensures that only relevant information is passed on to the operators. Ultra-precise detection reveals the exact position of the incident, eliminates uncertainties, and saves time.

What do you want to protect?

You can monitor a lot of critical assets and infrastructures with a DAS system; power plants, airports, borders, large facilities, pipelines, etc.

Low phase-noise, narrow linewidth, and long coherence length are essential

Our Koheras lasers are a suitable choice for DAS systems due to their industrial design, their inherent low-noise properties, and their stable performance that is unaffected by different environmental conditions and wide temperature ranges in the field.

World-leading acoustic sensing systems use our Koheras lasers due to the intrinsic low phase-noise, the narrow linewidth, and the long coherence length that enable measurement ranges of around 100 km.

The most reliable low-noise lasers on the market

Our fiber laser design is inherently compact and robust. It is developed for a long lifetime in demanding environments where uptime is critical. With documented low failure rates, we proudly deliver the most reliable low-noise lasers on the market.

We have more than 10,000 Koheras lasers deployed in the harshest environments on – and off – the planet. We have lasers on oil-rigs, in submarines, on wind turbines, and even in space. With over 20 years of experience, we know they last.

 

Features

  • ­Low phase-noise and long coherence length provide sensing distances of +100 km
  • Accurate pinpointing of intrusion or threat
  • Industrial reliability due to robust laser design
  • Designed for OEM-integration

 

Contact us now