Abstract: An optical sensing system for detecting fiber events along an optical cable under test (CUT) having forward and feedback fibers and multiple pairs of optical couplers interconnected along the forward and feedback fibers in a ladder topology. An optical transmitter generates an optical probing signal for a forward fiber, wherein the couplers along the forward fiber provide tapped portions of the probing signal to the couplers along a feedback fiber to form a combined optical feedback signal in the feedback fiber. A reference coupler is connected between the transmitter and the forward fiber to tap an optical reference signal from the probing signal, and a feedback coupler is connected to combine the reference signal and the feedback signal. An optical receiver receives and processes the combined reference and feedback signals from the feedback coupler to detect fiber events along the CUT.

Abstract: An optical sensing system for detecting fiber events along an optical cable under test (CUT) having forward and feedback fibers and multiple pairs of optical couplers interconnected along the forward and feedback fibers in a ladder topology. An optical transmitter generates an optical probing signal for a forward fiber, wherein the couplers along the forward fiber provide tapped portions of the probing signal to the couplers along a feedback fiber to form a combined optical feedback signal in the feedback fiber. A reference coupler is connected between the transmitter and the forward fiber to tap an optical reference signal from the probing signal, and a feedback coupler is connected to combine the reference signal and the feedback signal. An optical receiver receives and processes the combined reference and feedback signals from the feedback coupler to detect fiber events along the CUT.

Abstract: The invention relates to a system and a method for transmission over optical fiber (130) with mode or core scrambling. The system comprises a spatio-temporal encoder (110) and a plurality of modulators (1251, . . . , 125n) associated, respectively, with separate propagation modes or cores of said fiber, each modulator modulating a laser beam. Said fiber comprises a plurality of slices (1301, . . . , 130L), an amplifier (140l) being provided between any two consecutive slices of the optical fiber. A mode scrambler (150l) is associated with each amplifier in order to perform a permutation of said modes between at least two consecutive slices.

Abstract: The invention relates to a mode selection method for a system for MIMO transmission on an optical fiber of multimode type. It comprises a step of measuring the transfer matrix of the transmission channel made up of a set of modes of the optical fiber (110), a step of transforming (120) the transfer matrix into a block diagonal matrix, each block being associated with a mode subset, a step of determining (130) the gain and/or the transmission capacity for each of the mode subsets, and a selection (140) of the mode subset corresponding to the highest gain and/or capacity, the MIMO transmission system then using only the modes of the subset thus selected to transmit on the optical fiber. The invention relates also to a core selection method for a system for MIMO transmission on optical fiber of multicore type.

Abstract: The invention relates to a mode selection method for a system for MIMO transmission on an optical fiber of multimode type. It comprises a step of measuring the transfer matrix of the transmission channel made up of a set of modes of the optical fiber (110), a step of transforming (120) the transfer matrix into a block diagonal matrix, each block being associated with a mode subset, a step of determining (130) the gain and/or the transmission capacity for each of the mode subsets, and a selection (140) of the mode subset corresponding to the highest gain and/or capacity, the MIMO transmission system then using only the modes of the subset thus selected to transmit on the optical fiber. The invention relates also to a core selection method for a system for MIMO transmission on optical fiber of multicore type.

Abstract: The invention relates to a system and a method for transmission over optical fiber (130) with mode or core scrambling. The system comprises a spatio-temporal encoder (110) and a plurality of modulators (1251, . . . , 125n) associated, respectively, with separate propagation modes or cores of said fiber, each modulator modulating a laser beam. Said fiber comprises a plurality of slices (1301, . . . , 130L), an amplifier (140l) being provided between any two consecutive slices of the optical fiber. A mode scrambler (150l) is associated with each amplifier in order to perform a permutation of said modes between at least two consecutive slices.