What Makes The System?

A Distributed Acoustic Sensing System comprises of three discrete sub-systems

SENSOR 

An optical fiber cable, usually single mode, is embedded within or attached to the structure being monitored 

INTERROGATOR 

An optoelectronic unit that interrogates the optical fiber cable and detects the backscattered optical signal from the fiber. 

PROCESSOR 

A Processing Unit, often simply a PC, which takes detected data from the interrogator and performs further data processing, user interfacing, data transmission, and storage functions.  

How Does It Work?

Distributed Acoustic Sensing (DAS) defines as a system capable of continuously mapping strain and acoustic signals at high frequencies and high spatial resolution across a single strand of optical fiber, as the measuring medium. 

DISTRIBUTED ACOUSTIC SENSING SCIENCE 

Distributed acoustic sensing can be obtained from Rayleigh light scattering processes and is a consequence of interaction between electromagnetic (EM) wave, the probe pulse, and molecules of the medium, i.e. optical fiber. Rayleigh based DAS relies entirely on the relative motion of inhomogeneities in the sensing fiber. Any fluctuation in the relative motion due to variations in temperature and strain of the sensing fiber affects the phase and intensity of the Rayleigh scattered light in the sensing fiber.  

The Fibervis Solution

BEST PRICE TO PERFORMANCE RATIO

There are many other factors that should be involved in the decision making of a DAS system where this article does not define in detail. Here at Fibervis, we design and develop DAS systems to produce the best performance to cost value to the industry.

xDAS is a interferometric distributed acoustic sensing system, providing highly precise nano-strain/acoustic amplitude measurements in time, frequency domain over long distances. xDAS is made unique that it does not only provide the above features, but is made open and flexible to all applications, providing raw strain data. The system boast capability of nano strain measurements, +40km sensing range with selectable sampling resolution down to 50cm suitable for oil and gas, structural health, subsea, transportation, seismology monitoring. Do consult us for further information.