Cable Fault Characterization by Time-Domain Analysis From S-Parameter Measurement and Sparse Inverse Chirp-Z Transform

• Published in: IEEE sensors journal Vol. 21; no. 2; pp. 1009 - 1016
• Main Authors: Heim Weber, Guilherme, de Moura, Hector Lise, Pipa, Daniel Rodrigues, Martelli, Cicero, Silva, Jean Carlos Cardozo da, Silva, Marco Jose da
• Format: Journal Article
• Language: English
• Published: New York IEEE 15-01-2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Cables; Chirp; Discrete Fourier transforms; Frequency-domain analysis; ICZT; Parameters; Reflection; S-parameters; Scattering parameters; sparse analysis; Time domain analysis; Z transforms
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2020.2990929

Cable fault characterization usually requires time-domain profiles to locate and quantify failures. These profiles may be obtained from S-Parameters measured in the frequency domain through inverse Fourier methods. The Chirp Z Transform is a common approach for obtaining time-domain parameters from measured S-parameters. Most existing methods employ the Inverse Chirp Z Transform by a minimum norm solution, which does not have strong physical support. In this paper, we propose a Sparse Inverse Chirp Z Transform approach, specially designed for sparse time-domain signals representing localized fault locations in cables. Two algorithms are proposed to perform the conversion: OMP and FISTA. Their performances are verified in comparison with reference values, showing good agreement for both simulated and experimental data.