Bringing you the best of both worlds: the engineered fibre optic sensing system combining the extensive, high density coverage of distributed acoustic sensors with sensitivity beyond that of point sensors.
Carina is a versatile fibre optic sensing system and comprises an advanced optoelectronics interrogator and sensing cables, which are equipped with the new family of engineered Constellation fibres; to gain two orders of magnitude more sensitivity (100x or 20dB improvement) over that achieved with standard fibres.
Silixa has led the way in the development of high performing distributed fibre optic sensors since 2007; the intelligent Distributed Acoustic Sensor (iDAS™) is at the forefront of DAS performance in terms of stability, range, spatial resolution and phase coherency.
Applications such as borehole seismic, well production profiling, pipeline leak detection and perimeter security have benefited from the inherent nature of the technology whereby a standard optical fibre acts as a huge sensor array.
Now a transformative performance improvement has been achieved by advancing the state of the iDAS optoelectronics interrogator architecture, together with the introduction of new and proprietary Constellation fibre. This fibre is engineered to provide bright scatter centres along its length to capture and reflect more light back to the interrogator. This is achieved without introducing significant loss to the forward propagating laser pulses.
For the first time, with Carina Sensing System, it is possible to achieve the massive coverage of distributed sensors without having to compromise on sensitivity.
The significance of this step change in performance is most acute in applications with low acoustic signal levels such as is common with leak detection and production monitoring, where acoustic information can be present at, or below, the inherent system noise floor of the current technology and therefore difficult to detect.
Borehole seismic applications stand to benefit from greatly reduced source effort required to achieve high quality, densely sampled seismic data leading to significantly reduced operating time and costs. The higher sensitivity also paves the way for passive seismic and microseismic monitoring across the large aperture of the fibre and enables the possibility of vast, cost effective, sensing arrays using a single cable.
In addition to standard singlemode and multimode optical fibres, a family of Constellation fibres can be incorporated into a number of different cable types for downhole and surface deployment. Silixa also offers an intervention solution using this technology where the fibres are integrated into a hybrid electric-line cable.