Abstract: A novel method for automatically analyzing reflectograms in order to classify impedance discontinuities detected via their temporal or spectral signatures into various categories relating to potential faults or other physical elements present on the cable. A method for detecting the mutual influence of neighboring pulses in a reflectogram in order to separate them so as to isolate them and characterize each pulse accurately.

Abstract: A system for monitoring the state of a cable, includes a plurality of transferometry devices capable of injecting a test signal into the cable and measuring a signal being propagated in the cable, the transferometry devices being positioned along the cable so as to break down the cable into successive sections, the system comprising a control member capable of communicating with the transferometry devices and configured so as to perform at least one transferometry test consisting in injecting a test signal into the cable by means of a first transferometry device and measuring the test signal after its propagation in the cable by means of a second transferometry device different from the first device, the system comprising a post-processing member capable of communicating with the transferometry devices and configured to compare the measured signal to a reference signal to deduce therefrom an indicator of degradation of the section of cable disposed between the first transferometry device and the second transf

Abstract: A system for monitoring the state of a cable, includes a plurality of transferometry devices capable of injecting a test signal into the cable and measuring a signal being propagated in the cable, the transferometry devices being positioned along the cable so as to break down the cable into successive sections, the system comprising a control member capable of communicating with the transferometry devices and configured so as to perform at least one transferometry test consisting in injecting a test signal into the cable by means of a first transferometry device and measuring the test signal after its propagation in the cable by means of a second transferometry device different from the first device, the system comprising a post-processing member capable of communicating with the transferometry devices and configured to compare the measured signal to a reference signal to deduce therefrom an indicator of degradation of the section of cable disposed between the first transferometry device and the second transf

Abstract: A method for detecting soft faults in a transmission line includes the following steps: acquiring a measurement, called time-domain reflectogram, of a signal characteristic of the reflection of a reference signal previously injected into the line, determining the difference between the time-domain reflectogram and a time-domain reflectogram measured previously for the same line or an identical line of similar characteristics, in order to obtain a corrected time-domain reflectogram, applying a plurality of independent transformations to the corrected time-domain reflectogram in order to obtain a plurality of independent transformed reflectograms, converting the transformed reflectograms into a plurality of mutually independent probabilities of occurrence of a fault, applying a data merging method to the probabilities of occurrence of a fault to deduce therefrom a unified value of the probability of occurrence of a fault.

Abstract: A method for analyzing a cable into which a reference signal s of time support limited to a duration T is injected comprises the following steps: calculating the intercorrelation, in a sliding window of duration D at least equal to 2T, between the injected reference signal s and a measurement r of the reflection of the reference signal s in the cable, normalizing the calculated intercorrelation by a factor dependent on the integration of the reflection measurement r over the same sliding window of duration D.

Abstract: A method for characterizing a fault affecting a cable in which a reference signal s of limited time support is injected and a measurement r of the reflection of the reference signal s in the cable is taken, comprises the following steps: identifying a section of the measurement r corresponding to a fault, this measurement section being called the signature of the fault; generating a modified reference signal s?, of parameterizable amplitude, equal to the sum of the reference signal s and of the reference signal s inverted and delayed by a parameterizable delay; determining conjointly the values of the parameterizable delay and of the parameterizable amplitude that minimize the error between the modified reference signal s? and the signature of the fault; and deducing therefrom an estimation of the length of the fault from the determined value of the delay.

Abstract: A method for detecting soft faults in a transmission line includes the following steps: acquiring a measurement, called time-domain reflectogram, of a signal characteristic of the reflection of a reference signal previously injected into the line, determining the difference between the time-domain reflectogram and a time-domain reflectogram measured previously for the same line or an identical line of similar characteristics, in order to obtain a corrected time-domain reflectogram, applying a plurality of independent transformations to the corrected time-domain reflectogram in order to obtain a plurality of independent transformed reflectograms, converting the transformed reflectograms into a plurality of mutually independent probabilities of occurrence of a fault, applying a data merging method to the probabilities of occurrence of a fault to deduce therefrom a unified value of the probability of occurrence of a fault.

Abstract: A method for analyzing a cable into which a reference signal s of time support limited to a duration T is injected comprises the following steps: calculating the intercorrelation, in a sliding window of duration D at least equal to 2T, between the injected reference signal s and a measurement r of the reflection of the reference signal s in the cable, normalizing the calculated intercorrelation by a factor dependent on the integration of the reflection measurement r over the same sliding window of duration D.

Abstract: A method for characterizing a fault affecting a cable in which a reference signal s of limited time support is injected and a measurement r of the reflection of the reference signal s in the cable is taken, comprises the following steps: identifying a section of the measurement r corresponding to a fault, this measurement section being called the signature of the fault; generating a modified reference signal s?, of parameterizable amplitude, equal to the sum of the reference signal s and of the reference signal s inverted and delayed by a parameterizable delay; determining conjointly the values of the parameterizable delay and of the parameterizable amplitude that minimize the error between the modified reference signal s? and the signature of the fault; and deducing therefrom an estimation of the length of the fault from the determined value of the delay.

Abstract: The invention relates to a method and a device for analyzing electric cables in a network, for the detection and location of defects in networks comprising at least one junction from which there depart N secondary cable stretches. The method includes interposing in the network, in series at the input of each the secondary stretches (T2, T3) starting from the junction (A), a respective bidirectional passive filter (FR2,FR3) able to cut off a frequency band associated with this stretch. The filters all allow through the useful frequencies for the normal operation of the network. A pulsed test is applied to the input of the network signal modulated by N different carrier frequencies each situated in one of the N frequency bands of the filters. The temporal position of test signal spikes reflected for each of the N frequencies is detected, and deducing therefrom the position of possible defects on a stretch of cable of the network.

Abstract: The invention relates to a method and a device for analyzing electric cable networks in order to detect and locate defects in the cables comprising at least one branch connection from which N secondary sections extend. The method involves injecting into the network, at a plurality of injection points E, pseudo-random sequences of digital signals PNi(t) that are de-correlated from each other, and collecting, at one or more observation points Sj, composite time signals Rj(t) generated by the circulation of the output sequences and the reflections thereof in the impedance discontinuities of the network. The correlation between the composite signals and the time-offset pseudo-random sequences is then computed, and the positions of correlation peaks are sought to deduce therefrom the positions of defects in the network by taking into account the signal propagation speed in the network.

Abstract: The invention relates to a method and a device for analyzing electric cables in a network, for the detection and location of defects in networks comprising at least one junction from which there depart N secondary cable stretches. The method includes interposing in the network, in series at the input of each the secondary stretches (T2, T3) starting from the junction (A), a respective bidirectional passive filter (FR2,FR3) able to cut off a frequency band associated with this stretch. The filters all allow through the useful frequencies for the normal operation of the network. A pulsed test is applied to the input of the network signal modulated by N different carrier frequencies each situated in one of the N frequency bands of the filters. The temporal position of test signal spikes reflected for each of the N frequencies is detected, and deducing therefrom the position of possible defects on a stretch of cable of the network.