An optical fiber sensing system according to the present disclosure includes: a cable (20) including optical fibers; a reception unit (31) configured to receive, from at least one optical fiber included in the cable (20), an optical signal on which a vibration detected in each of a plurality of locations on the cable (20) is superimposed; and an action specifying unit (32) configured to specify, based on the optical signal, a location on the cable (20) in which the vibration has been detected and specify an action of a target to be monitored which has caused the vibration, in which the action specifying unit (32) specifies a detection pattern that is used to specify the action of the target to be monitored depending on the environment of the location on the cable (20) in which the vibration has been detected.

Described herein are methods and systems of distributed acoustic sensing, such as in an urban or metropolitan area involving a dedicated and established fibre optic communications network including a data centre. In general, the disclosed method and system includes the steps of (a) selecting an optical fibre cable installation having a path extending across a selected geographical area, the optical fibre cable installation including a bundle of optical fibres and forming part of a fibre-optic communications network, (b) determining characteristics associated with the optical fibre and/or the selected optical fibre installation, (c) transmitting outgoing light in the optical fibre, (d) receiving reflected light back scattered along the optical fibre, and (e) based on the reflected light and the determined characteristics, generating an alert signal representative of an acoustic event. The disclosed method and system are applied to detect acoustic events near or within the selected geographical area.

Described herein are methods and systems of distributed acoustic sensing, such as in an urban or metropolitan area involving a dedicated and established fibre optic communications network including a data centre. In general, the disclosed method and system includes the steps of (a) selecting an optical fibre cable installation having a path extending across a selected geographical area, the optical fibre cable installation including a bundle of optical fibres and forming part of a fibre-optic communications network, (b) determining characteristics associated with the optical fibre and/or the selected optical fibre installation, (c) transmitting outgoing light in the optical fibre, (d) receiving reflected light back scattered along the optical fibre, and (e) based on the reflected light and the determined characteristics, generating an alert signal representative of an acoustic event. The disclosed method and system are applied to detect acoustic events near or within the selected geographical area.

An optical fiber sensing system according to this disclosure includes: a cable (20) including optical fibers; a reception unit (31) configured to receive, from at least one optical fiber included in the cable (20), an optical signal having a pattern in accordance with a state of a target to be monitored; and a monitoring unit (32) configured to specify the location of the target to be monitored based on the pattern that the optical signal has and specify the trajectory of the target to be monitored based on a locational variation of the specified location.

An optical fiber sensing system according to this disclosure includes: a cable (20) including optical fibers; a reception unit (31) configured to receive, from at least one optical fiber included in the cable (20), an optical signal having a pattern in accordance with a state of a target to be monitored; and a monitoring unit (32) configured to specify the location of the target to be monitored based on the pattern that the optical signal has and specify the trajectory of the target to be monitored based on a locational variation of the specified location.

Described herein are methods and systems of distributed acoustic sensing, such as in an urban or metropolitan area involving a dedicated and established fibre optic communications network including a data centre. In general, the disclosed method and system includes the steps of (a) selecting an optical fibre cable installation having a path extending across a selected geographical area, the optical fibre cable installation including a bundle of optical fibres and forming part of a fibre-optic communications network, (b) determining characteristics associated with the optical fibre and/or the selected optical fibre installation, (c) transmitting outgoing light in the optical fibre, (d) receiving reflected light back scattered along the optical fibre, and (e) based on the reflected light and the determined characteristics, generating an alert signal representative of an acoustic event. The disclosed method and system are applied to detect acoustic events near or within the selected geographical area.

Described herein are methods and systems of distributed acoustic sensing, such as in an urban or metropolitan area involving a dedicated and established fibre optic communications network including a data centre. In general, the disclosed method and system includes the steps of (a) selecting an optical fibre cable installation having a path extending across a selected geographical area, the optical fibre cable installation including a bundle of optical fibres and forming part of a fibre-optic communications network, (b) determining characteristics associated with the optical fibre and/or the selected optical fibre installation, (c) transmitting outgoing light in the optical fibre, (d) receiving reflected light back scattered along the optical fibre, and (e) based on the reflected light and the determined characteristics, generating an alert signal representative of an acoustic event. The disclosed method and system are applied to detect acoustic events near or within the selected geographical area.

A system and method for detecting degradation of a fiber optic in a strap of a body-worn device that is removably attached to an appendage or other location of a person or animal. A fiber optic is embedded within the strap. A light source emits light energy through the optical interface and into the fiber optic and a light sensor receives and detects light energy from the fiber optic. If the light energy is not received and detected from the fiber optic, the light energy is increased until the light energy is received and detected or reaches a maximum light energy at which time tampering is declared. If the light energy reaches a pre-determined threshold which is less than the maximum light energy, it is declared that the body-worn device requires servicing.

A system and method for detecting degradation of a fiber optic in a strap of a body-worn device that is removably attached to an appendage or other location of a person or animal. A fiber optic is embedded within the strap. A light source emits light energy through the optical interface and into the fiber optic and a light sensor receives and detects light energy from the fiber optic. If the light energy is not received and detected from the fiber optic, the light energy is increased until the light energy is received and detected or reaches a maximum light energy at which time tampering is declared. If the light energy reaches a pre-determined threshold which is less than the maximum light energy, it is declared that the body-worn device requires servicing.

In some embodiments, optical fiber monitoring may be facilitated. In some embodiments, monitoring of an optical fiber may be performed via a detection system to detect changes in the optical fiber that are indicative of one or more events. During the monitoring, a monitor signal may be transmitted along the optical fiber via a light source, where the monitor signal is received by the detection system as light from the optical fiber. While the detection system continues to receive light from the optical fiber in connection with the transmitting of the monitor signal, a test disturbance event may be caused to occur at a predetermined location along the optical fiber via a device at the predetermined location. In response to a failure of the detection system to detect test-related changes in the optical fiber caused by the test disturbance event, a notification indicating an issue may be generated.