Method for improving fault detection and positioning precision using reflectometry in a wired electrical network

A device for fault detection and positioning by reflectometry in a wired electrical network, said device comprising:

• a synchronization module that generates an emission clock signal and a reception clock signal;
• an emission module that injects a test signal into a cable of said network a number N times, where N is an integer, and a timing of successive injections is controlled by the synchronization module;
• a reception module that retrieves a reflected signal for each injected test signal, wherein said reception module samples each reflected signal at a frequency Fe=1/Te, where Te is a sampling period;
• and
• a test module that counts a number of samples obtained for the reflected signal and compares the number of samples obtained with a number n predefined as a function of a length of the cable or the electrical network to be diagnosed, where n is an integer,
• wherein the test module causes the emission module to repeatedly inject N test signals, obtains samples for corresponding N reflected signals, and counts a number of samples corresponding to the N reflected signals, shifting the emission clock signal by a duration δ,
• wherein the test module reconstitutes the reflected signal from n*N samples obtained, and analyzes the reconstituted reflected signal to detect a fault, and
• wherein, the successive injections of a test signal into a cable of said network are desynchronized from the sampling period Te by a duration δ1, and a first sample of the reflected signal for each injecting signal is retrieved and desynchronized by a duration δ2 from the duration δ1, the following samples of said reflected signal being retrieved with a constant delay that is a multiple of the sampling period Te relative to said first sample.