The dielectric constant values of cloths (fabric materials) like polyester, polyester combined cotton including, jeans cotton, can be found using resonance method. This method uses a microstrip patch radiator, which contains fabric material as its substrate. The accurate value of the dielectric constant of the fabric material can easily be extracted from the measured resonant frequency of the patch radiator.

The dielectric constant values of cloths (fabric materials) like polyester, polyester combined cotton including, jeans cotton, can be found using resonance method. This method uses a microstrip patch radiator, which contains fabric material as its substrate. The accurate value of the dielectric constant of the fabric material can easily be extracted from the measured resonant frequency of the patch radiator.

The most staight forward method to measure the dielectric constant of any material is to make from it a parallel plate capacitor with known area and filled with the material to be measured. The practical way is to use aluminum foils as electrodes. Then after making the capacitor one measures it using a Q meter of an RLC meters.

Best wishes

Mr Zekry's method is probably best at low frequencies and Mr Pandey's method at microwave frequencies. To some extent they are similar in that the results for both depend on the capacitance between parallel plates.

I have never used a Q meter or RLC meter and don't know if they work at microwave frequencies, 10 GHz, for instance.

Welcome Malcolm,

The Q meter is suitable for measurement at radio frequencies. It is so that i assumed that the textile polarization is either ionic or electronic polarization therefore, the dielectric constant will remain constant even in the microwave frequencies.

Thank you for your comment.

Best wishes

Thank you Abdelhalim abdelnaby Zekry Sir and Malcolm White Sir. That cleared my query

Thank you Anil Kumar Pandey Sir. Got it cleared..

Hi,

You can measure broadband dielectric properties of your clothing materials using open ended coaxial probe technique. We have performed such measurements many times (however, there are certain measurement challenges).