The use of the Pseudo Wigner Ville Transform for detecting soft defects in electric cables

As the complexity of wiring networks increases, their reliability becomes a major issue. One of the current challenges to tackle is the detection of soft faults before they become more serious defects, such as short or open circuits. As these faults can have heavy consequences on the safety of a system (such as stopping a process, loss of information or even fires), it is important to detect them as early as possible. This requires the use of very efficient wiring diagnostic tools. Recently a method called JTFDR (Joint Time Frequency Domain Reflectometry) has been proposed. It is based on the use of the Wigner Ville Transform (WVT). However the quadratic nature of this time frequency transform generates the presence of unwanted cross terms, which can lead to false detection. This article proposes to use the Pseudo Wigner Ville Transform (PWVT) in order to attenuate the cross-terms effect and therefore enhance the diagnosis quality.