Improvement of detection performance in STDR/SSTDR using sign detector

Novel fault detection schemes for sequence time-domain reflectometry (STDR) and spread-spectrum time-domain reflectometry (SSTDR) are proposed, which improve, the detection performance of far faults without increasing the computational complexity by positioning a sign detector at the front of the time correlator. Simulation results demonstrate that the detection performances of the proposed schemes for far faults are considerably better than those of the conventional ones regardless of sequence lengths and reference types.