Abstract: A method for detecting a structural fault in a structure includes the steps of, (a) performing a Brillouin measurement at a point along a sensing optical fiber which operably cooperates with the structure, to obtain a Brillouin gain spectrum at that point; (b) identifying at least two curves which, when added together, best fit the Brillouin gain spectrum; (c) identifying if peaks of the least two curves occur at different frequencies so as to determine if the structure has a structural fault. There is further provided a corresponding apparatus for detecting a structural fault in a structure.

Abstract: Brillouin optical distributed sensing device and method is provided and includes a structure for generating an optical pulsed signal and an optical probe signal. The structure includes a circulation component for directing the optical pulsed signal to a sensing optical fiber, and directing an optical measurement signal with Brillouin scattering information arising from the sensing optical fiber toward a detection apparatus.

Abstract: A method for detecting a structural fault in a structure includes the steps of, (a) performing a Brillouin measurement at a point along a sensing optical fiber which operably cooperates with the structure, to obtain a Brillouin gain spectrum at that point; (b) identifying at least two curves which, when added together, best fit the Brillouin gain spectrum; (c) identifying if peaks of the least two curves occur at different frequencies so as to determine if the structure has a structural fault. There is further provided a corresponding apparatus for detecting a structural fault in a structure.

Abstract: A sensing cable designed for distributed pressure sensing includes one or more optical fibres which have a continuous weak fiber Bragg grating permanently written inside a core of the optical fiber. The sensing cable is configured so that pressure applied to the sensing cable changes birefringence in the one or more optical fibers.

Abstract: A Brillouin optical distributed sensing device and method includes a structure for generating an optical pulsed signal and an optical probe signal. Includes is a circulation component for directing the optical pulsed signal to a sensing optical fiber and for directing an optical measurement signal with Brillouin scattering information arising from the sensing optical fiber toward a detection apparatus. Also included is an optical routing component for configuring the device to allow generating: (i) according to a first configuration, an optical measurement signal with stimulated Brillouin scattering information resulting from the interaction of the optical pulsed signal, and an optical probe signal propagating in the sensing optical fiber in a direction opposite to the optical pulsed signal, or (ii) according to a second configuration, an optical measurement signal with spontaneous Brillouin scattering information resulting from the propagation of the optical pulsed signal in the sensing optical fiber.

Abstract: A sensing cable including one or more optical fibers and a coating which is provided on the one or more optical fibers. The coating is configured so that pressure applied to the sensing cable, along one or more axes, induces less lateral compression on the one or more optical fibers than pressure applied to the sensing cable along one or more other axes so as to change birefringence in the one or more optical fibers.