Outdoor application of distributed fiber optic sensing / acoustic sensing
Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously sense/monitor outdoor facilities and structures including outdoor cabinets containing fiber optic facilities in which the cabinet/fiber optic cable contained therein are configured to provide superior acoustic sensing. Further outdoor facilities and structures that are monitored include manhole structures. Superior DFOS/DAS monitoring results are obtained by employing a machine learning-based analysis method that employs a temporal relation network (TRN).
1 . A distributed fiber optic sensing (DFOS) system comprising:
a length of optical fiber sensor cable;
a DFOS interrogator system in optical communication with the length of optical fiber sensor cable;
an intelligent analyzer configured to analyze DFOS sensing data received by the DFOS interrogator system;
the distributed fiber optic sensing (DFOS) system CHARACTERIZED BY
an outdoor fiber cabinet in positioned in an optical path of the length of optical fiber sensor cable, the outdoor fiber cabinet configured to amplify acoustic vibration waves and mechanically convey the acoustic vibration waves to the optical fiber sensor cable such that acoustic vibration signals are detected by the intelligent analyzer;
wherein at least a portion of the outdoor fiber cabinet is configured as a fiber microphone/amplifier and includes a fiber coil formed from the optical fiber sensor cable;
wherein the fiber coil formed from the optical fiber sensor cable is mechanically mounted to the portion of the outdoor fiber cabinet configured as a fiber microphone/amplifier;
wherein the portion of the outdoor fiber cabinet configured as a fiber microphone/amplifier includes an interaction area that interacts with acoustic vibration waves; and
wherein the outdoor fiber cabinet configured as a fiber microphone/amplifier is a door.
2 . The system of claim 1 wherein the intelligent analyzer is configured to detect whether the door is open or closed.
3 . The system of claim 2 wherein the intelligent analyzer is configured to detect whether an open/closed status of the door is authorized.
4 . The system of claim 3 wherein the portion of the outdoor fiber cabinet configured as a fiber microphone/amplifier is constructed from a metal.
5 . The system of claim 4 wherein the optical fiber sensor cable carries telecommunications traffic simultaneously with any DFOS signals.
6 . A distributed fiber optic sensing (DFOS)/distributed acoustic sensing (DAS) system comprising:
a length of optical fiber sensor cable;
a DFOS/DAS interrogator system in optical communication with the length of optical fiber sensor cable; and
an AI-intelligent analyzer including a temporal relation neural network (TRN) configured to provide temporal relation event detection in DFOS sensing data received by the DFOS interrogator system.
7 . The system of claim 6 further comprising one or more manholes in which at least a portion of the length of optical fiber sensor cable resides.
8 . The system of claim 7 wherein the TRN is trained to obtain training patches having desired spatial and temporal resolution.
9 . The system of claim 8 where the TRN training includes a filter to smooth signals and select a candidate high vibration patch based on intensity.
10 . The system of claim 9 wherein a TRN model is trained with label and patch pairs.
11 . The system of claim 10 wherein TRN model determines if an open or close event exists within a patch and an AI engine receives as input continuous streams of input data and performs inference in real-time, providing timestamps, event types, and confidence scores as output.