Truly Distributed Coaxial Cable Sensing based on Random Inhomogeneities
Rayleigh backscattering-based distributed fiber optic sensing technology is well known and widely used for large-scale structural health monitoring. Inspired by the Rayleigh backscattering-based sensing methodology on an optical fiber, in this paper, we present a sensing concept based on the random inhomogeneities on a coaxial cable. As an analogy of Rayleigh backscattering along an optical fiber length, 'backscattering' also exists from a commercial coaxial cable due to its inherent defects along a cable length which induce a local variation (i.e., impedance mismatch). This is because of the irregular microscopic structures of the inner/outer conductors, and the inhomogeneous density or permittivity of the inner dielectrics after the cables are manufactured. The accumulated backscattered signals along the coaxial cable can be obtained using frequency-domain reflectometry. By analyzing the shift in the local backscattered signal, the local environmental perturbations (e.g., local strain or temperature) can be determined, so that truly distributed sensing capability using a coaxial cable can be achieved. To verify the proposed concept, an intact and commercial coaxial cable was demonstrated for distributed temperature sensing. Compared with the existing coaxial cable-based distributed sensing technologies, the proposed sensing concept does not need extra modifications to the coaxial cable and offers a truly distributed sensing capability.
C. Zhu et al., "Truly Distributed Coaxial Cable Sensing based on Random Inhomogeneities," IEEE Transactions on Instrumentation and Measurement, vol. 68, no. 11, pp. 4600-4607, Institute of Electrical and Electronics Engineers (IEEE), Jan 2019.
The definitive version is available at https://doi.org/10.1109/TIM.2018.2890327
Electrical and Computer Engineering
Keywords and Phrases
Coaxial Cable; Distributed Sensing; Random Inhomogeneities; Rayleigh Backscattering; Temperature Sensing
International Standard Serial Number (ISSN)
Article - Journal
© 2019 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.
15 Jan 2019