Measurement of the surface resistance of conductive textiles at microwave frequency

Textile samples which consist of conductive threads are characterized in a microwave frequency range. The configurations of the threads used in this study are traditional ones which have no metallic wires or filaments and have been used in decoration in clothing for hundred years. A half-wavelength microstrip line resonator is fabricated and the Q factors are measured for a copper strip line and for the strip of sample textile from the frequency responses. Difference of Q factors in the two cases leads to the relationship between the surface resistances of the sample and a copper sheet. Then the surface resistances of the samples as conductive sheets are listed and compared. It is found that the relative resistivity is less than four for some textiles. These conductive textiles using a traditional technology are expected to use in wearable electrical systems.