Spread spectrum reflectometry for the simultaneous diagnosis of shielded cable bundles

Simultaneous diagnosis of multiple cables is a new research topic that focuses on reducing the weight, volume and computing time of fault-locating devices. For condition monitoring of energised cables, Spread Spectrum Reflectometry (SSR) has been extensively used. SSR includes Sequence Time Domain Reflectometry (STDR) and Spread Spectrum Time Domain Reflectometry (SSTDR) techniques. Recent research works have proposed the use of STDR for the simultaneous diagnosis of multiple cables. However, noise and interference limit the system’s ability to identify small faults. In this paper, we conduct a detailed analysis of the application of the SSR method to simultaneous diagnosis of noisy cable bundles. The system is evaluated using the Detection Error Rate (DER) as a function of Signal-to-Noise Ratio (SNR), false alarm threshold, and fault location. To select the optimal spreading sequences’ set for SSR, the performances of various sequences with good correlation properties were compared.