Analysis of spread spectrum time domain reflectometry for wire fault location

• Published in: IEEE sensors journal Vol. 5; no. 6; pp. 1469 - 1478
• Main Authors: Smith, P., Furse, C., Gunther, J.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-12-2005; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aging wire detection; Aircraft; arc detection; Cables; Circuit faults; Circuit testing; Delay; Fault location; Reflectometry; sequence time domain reflectometry (STDR); Spread spectrum communication; spread spectrum time domain reflectometry (SSTDR); Time domain analysis; time domain reflectometry (TDR); Wire; wire fault detection
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2005.858964

Spread spectrum time domain reflectometry (SSTDR) and sequence time domain reflectometry have been demonstrated to be effective technologies for locating intermittent faults on aircraft wires carrying typical signals in flight. This paper examines the parameters that control the accuracy, latency, and signal to noise ratio for these methods. Both test methods are shown to be effective for wires carrying ACpower signals, and SSTDR is shown to be particularly effective at testing wires carrying digital signals such as Mil-Std 1553 data. Results are demonstrated for both controlled and uncontrolled impedance cables. The low test signal levels and high noise immunity of these test methods make them well suited to test for intermittent wiring failures such as open circuits, short circuits, and arcs on cables in aircraft in flight.