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Shielding effectiveness measurements and uncertainty estimation for textiles by a VNA-based free space transmission method

Published online by Cambridge University Press:  07 November 2013

S.M. Patel*
Quantum Phenomenon and Applications, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-12, India
K. Patel
Silicon Thin Film Solar Cells, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-12, India
P.S. Negi
Electrical Standards, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-12, India
V.N. Ojha
Quantum Phenomenon and Applications, CSIR-National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-12, India
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A free-space transmission method has been used for reliable shielding effectiveness measurement of the easily available textile materials. Textiles with three different yarn densities were studied for their shielding effectiveness with the help of a vector network analyzer and laboratory calibrated two X-band horn antennas. The expressions of uncertainty estimation have been derived in accordance with the present free-space measurement setup for the calculated SE values. The measurements have shown that an electromagnetic energy can be maximum shielded up to 16.24 dB with measurement uncertainty less than 0.21 dB in 8.2 to 12.4 GHz range by a 160.85 μm textile. Thus, a thin textile with a high density can have higher shielding and this property mainly depends on its intrinsic structure, frequency range and thickness. This study promises the potential applications of such materials as a very cost effective shielding material at microwave frequencies with some modifications.

Research Article
© EDP Sciences 2013

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