Abstract: An object of the present invention is to provide a monitoring device and an optical fiber identification method capable of efficiently identifying an optical fiber at a construction site. The monitoring device 71 includes a light receiver 74 that receives an optical signal SL leaked from an optical fiber, a counter 75 that counts the number of unique numbers indicating transmission sources included in the optical signal SL, and a display unit 76 that displays the number of unique numbers. The monitoring device 71 further includes a control unit 77 that causes the display unit 76 to display that a portion where the optical signal SL has leaked is between the 8-branch splitter 51 and the OLT 11 when the number of unique numbers is two or more, and that causes the display unit 76 to display that it is unknown whether a portion where the optical signal SL has leaked is between the 8-branch splitter 51 and the OLT 11 or between the 8-branch splitter 51 and the ONU 21 when the number of unique numbers is one.

Abstract: An object of the present disclosure is to realize water immersion detection that does not require a replacement module, and does not cause any optical loss. The present disclosure relates to a device configured to measure guided acoustic wave Brillouin scattering in a measurement target optical fiber, and detect water immersion of the measurement target optical fiber based on a characteristic around a peak of the guided acoustic wave Brillouin scattering.

Abstract: The present disclosure is directed to enabling detection of microbending even in a case where a microbending loss varies. The present disclosure relates to a device that measures a transmission loss in a measured optical fiber to be targeted, and detects microbending in the measured optical fiber based on periodicity of the transmission loss.

Abstract: An object of the present disclosure is to detect a microbend in an optical fiber before the light-receiving intensity of a transmission device decreases. The present disclosure relates to a device configured to measure guided acoustic wave Brillouin scattering in a measurement target optical fiber, and detect a microbend in the measurement target optical fiber based on a characteristic around a peak of the guided acoustic wave Brillouin scattering.

Abstract: An object of the present disclosure is to realize water immersion detection that does not require a replacement module, and does not cause any optical loss. The present disclosure relates to a device configured to measure guided acoustic wave Brillouin scattering in a measurement target optical fiber, and detect water immersion of the measurement target optical fiber based on a characteristic around a peak of the guided acoustic wave Brillouin scattering.

Abstract: An object of the present invention is to provide an optical fiber test method, an optical fiber test apparatus, and a program, capable of detecting a boundary of an optical fiber line facility regardless of a change in a noise amount. A change amount (a differential value) of an OTDR waveform increases toward a distal end due to noise effects, making it difficult to determine a boundary of the optical fiber using the change amount. Therefore, in the present invention, a dispersion of the OTDR waveform, which increases toward a distal end due to noise effects, is also used to determine the boundary of the optical fiber. In other words, in the present invention, the noise amount is expressed by the dispersion, and the dispersion is compared with the change amount such as a differential value as a threshold, to determine the boundary of the optical fiber.

Abstract: An object of the present disclosure is to provide an optical fiber cable monitoring method and an optical fiber cable monitoring system capable of linking information obtained from a measurement result with information stored in a DB and accurately specifying a loss occurrence location on an optical fiber cable. The optical fiber cable monitoring method according to the present disclosure uses two types of optical fiber measurement techniques having different sensitivities. Each of closure locations on the optical fiber cable is acquired with a high-sensitivity measurement technique, and geographical location information and the closure locations on the optical fiber are linked in an arrangement order of the closures. Thus, an operator can recognize an actual location (geographical location information) of a closure that is linked to a location of a point of abnormality on the optical fiber cable when an abnormality in the closure is detected with a low-sensitivity measurement technique.

Abstract: An object of the present disclosure is to provide an optical fiber cable monitoring method and an optical fiber cable monitoring system capable of linking information obtained from a measurement result with information stored in a DB and accurately specifying a loss occurrence location on an optical fiber cable. The optical fiber cable monitoring method according to the present disclosure uses two types of optical fiber measurement techniques having different sensitivities. Each of closure locations on the optical fiber cable is acquired with a high-sensitivity measurement technique, and geographical location information and the closure locations on the optical fiber are linked in an arrangement order of the closures. Thus, an operator can recognize an actual location (geographical location information) of a closure that is linked to a location of a point of abnormality on the optical fiber cable when an abnormality in the closure is detected with a low-sensitivity measurement technique.