Patent application number | Description | Published |
20110069302 | Wide Area Seismic Detection - A method for monitoring for seismic events by interrogating an optic fibre which forms part of an existing communications infrastructure to provide distributed acoustic sensing (DAS). The signals provided by the distributed sensing provide measurements at each of a plurality of discrete portions along the fibre, which may be many tens of kilometres in length. Warning or measurement and consequently prediction of seismic activity can be provided by collecting data over a wide area, without the need to deploy a correspondingly large fibre network. | 03-24-2011 |
20110139538 | Tracking Objects in Conduits - Methods and apparatus for tracking objects in conduits, especially for tracking the movement of a pig in a pipeline, are disclosed. Distributed acoustic sensing is used to obtain signal returns from a plurality of discrete longitudinal sensing portions of a fibre optic cable which is laid along the length of the conduit. The method involves detecting an acoustic signature corresponding to the object moving in the conduit. The acoustic signature may comprise a series of pressure pulses caused by the object traversing joints etc. in the conduit. Preferably the method involves detecting pressure waves caused by the object as it moves through the conduit. Detecting the characteristic pressure wave signal provides discrimination of the object from other acoustic disturbances. In pipeline applications a pig can be tracked in real time, if the pig stops moving an alert can be generated and the location of the pig will be known. | 06-16-2011 |
20110149688 | Conduit Monitoring - A method for monitoring a fluid carrying conduit by introducing an acoustic pulse into the conduit, and interrogating an optic fibre positioned along the path of said conduit to provide distributed acoustic sensing. By measuring the response at each of a plurality of locations, a conduit condition profile can be derived. A condition profile can be obtained quickly and easily with minimum disruption to the pipeline infrastructure and contained flow. Existing optic fibres running along the path of a pipe can be employed for sensing purposes, allowing relatively long spans of pipeline to be monitored with only limited access to the pipe. | 06-23-2011 |
20120137781 | Fibre Optic Acoustic Sensing - This invention relates to the fibre optic distributed acoustic sensing to detect P and S waves in a solid medium. Distributed acoustic sensing can be achieved using an unmodified fibre optic by launching optical pulses into the fibre and detecting radiation which is Rayleigh backscattered there from. By analysing the returns in analysis bins, acoustic disturbances can be detected in a plurality of discrete longitudinal sections of the fibre. The present invention extends such fibre distributed acoustic sensing to detection of S and P waves. | 06-07-2012 |
Patent application number | Description | Published |
20120222487 | OPTIC FIBRES AND FIBRE OPTIC SENSING - Fibre optic cables with improved performance for use in distributed sensing, for instance in distributed acoustic sensors, are disclosed. In one embodiment a fibre optic cable ( | 09-06-2012 |
20120226452 | Improvements in Distributed Fibre Optic Sensing - Techniques for determining lateral offset of the source of an acoustic disturbance in a distributed acoustic fibre optic sensor are described. The sensor comprises an optical source ( | 09-06-2012 |
20120230628 | Distributed Fibre Optic Sensing - The invention relates to a distributed fibre optic sensor ( | 09-13-2012 |
20130139600 | Gunfire Detection - An apparatus and method for detecting gunfire is provided which uses distributed acoustic sensing to provide the gunfire detection. The method comprises interrogating an optical fibre with electromagnetic radiation to provide a distributed acoustic sensor comprising a plurality of sensing portions of the optical fibre, and analysing a measurement signal from said sensing portions to detect gunfire events. A gunfire event will typically be relatively intense but of short duration and affect multiple sensing channels. The method may detect a characteristic | 06-06-2013 |
20130151203 | Detection of Moving Objects - A system for moving object ( | 06-13-2013 |
20130154632 | Magnetic Field Detector - There is provided a system ( | 06-20-2013 |
20140159715 | Portal Monitoring - The present invention relates to a portal monitoring system that uses distributed sensing to detect metallic objects passing through the portal. The system comprises a length of fibre optic ( | 06-12-2014 |
20140355383 | Location and Monitoring of Undersea Cables - The present application described methods an apparatus for locating and/or monitoring subsea cables ( | 12-04-2014 |
20140362668 | Indicating Locations - This application describes methods and apparatus for remotely indicating a location of interest in an area, for instance the location of an event in the area. The method comprises positioning an acoustic source at the location of interest, activating the acoustic source to produce a predetermined acoustic output and performing distributed acoustic sensing on at least one optical fibre deployed at least partly in the area. The acoustic source thus acts as an acoustic marker which can be remotely detected by the distributed acoustic sensor. The acoustic signals detected by the distributed acoustic sensor are therefore analysed to detect said predetermined acoustic output and determine the location of the acoustic source. The method is particularly applicable to transport networks already provided with optical fibre along the length of the network and can be used to indicate the location of work parties or emergencies. | 12-11-2014 |