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A Q-band free-space characterization of carbon nanotube composites



Ahmed M. Hassan, Jan Obrzut, Edward Garboczi


We present a free-space measurement technique for non-destructive non-contact electrical and dielectric characterization of nano-carbon composites in the Q-band frequency range of 30 GHz to 50 GHz. The experimental system and error correction model accurately reconstruct conductivity of composite materials that are either thinner or thicker than the wave penetration depth. This error correction model implements a fixed wave propagation distance between antennas and corrects the complex scattering parameters of the specimen from two references, an air slab having geometrical propagation length equal to that of the specimen under test, and a metallic conductor, such as an aluminum plate. Experimental results were validated by reconstructing the relative dielectric permittivity of known dielectric materials and then used to determine the conductivity of nano-carbon composite laminates. This error correction model can simplify routine characterization of thin conducting laminates to just one measurement of scattering parameters, making the method attractive for research, development, and for quality control in the manufacturing environment.
IEEE Transactions on Microwave Theory and Techniques


microwave metrology, free space measurement, error-correction, non-contact non-destructive measurements, conducting nanocarbon composite


Hassan, A. , Obrzut, J. and Garboczi, E. (2016), A Q-band free-space characterization of carbon nanotube composites, IEEE Transactions on Microwave Theory and Techniques, [online],, (Accessed April 12, 2024)
Created September 18, 2016, Updated October 12, 2021