Effects of structural parameters of textile substrates on the novel textile conformal half-wave dipole antenna

Abstract

In the smart textile area, textile antennas integrated into people’s clothing functioning as the wireless signal transmission devices have gained increasing attention in recent decades. In this study, a textile conformal dipole antenna was designed to work at the frequency of 915 MHz. The radiation elements of the antenna were adhered directly onto the stitched polyester fabric substrate to get the conformal effect. The measured results showed that the antenna had good performance with the return loss value and typical omnidirectional radiation patterns. To investigate the effect of textile substrate on the antenna performance, models for stitched and plain weave structures were built and the value of root mean square (RMS) surface error was calculated using integration methods. Then an acceptable range of operation frequencies versus RMS was marked out for estimating the reliability of textile substrate. The calculated RMS of our designed antenna was 0.25 mm, which was in the acceptable range area indicating the proper antenna design. Finally, the relationships between the critical frequencies and fabric parameters such as yarn thickness and density were studied, which gives the direct guideline for selecting the fabric as the substrate for textile antennas.