Multiple Soft Defect Signature Magnification in Electrical Cables With Binary Time-Domain Reflectometry

Predictive maintenance of electrical cables consists of detecting defects as early as possible. The recently introduced a binary time-domain reflectometry (BTDR) method does not rely on expensive and complex digital-to-analog (DAC) and analog-to-digital (ADC) conversion components. A simple balancing device at the cable's interface enables direct amplification of the very low amplitude peaks of soft defects, without any data postprocessing or baselining. This low complexity system, made of a single controllable digital potentiometer, is driven by the programmable logic at the heart of the reflectometer. Previous results have shown that the magnification potential is distributed among all soft defects present on the line. We introduce a simple way to achieve maximum amplification for multiple soft defect peaks, with enhanced noise immunity.