Designs of Textile Antenna Arrays for Smart Clothing Applications

In this work, three designs of textile antennas, namely, a rectangular microstrip patch antenna, annular slot antenna, and planar inverted-F antenna (PIFA), operating in the 2.45 GHz WLAN band were developed for smart clothing applications. Conductive textile, a copper-plated polyester fabric, was used for fabricating antenna radiators and grounds. An insulating neoprene fabric with a thickness of 4 mm and a permittivity of 1.5 was used for preparing the substrates. The textile patch antenna achieved a maximum gain of 5.96 dBi and a bandwidth of 4.6%. The annual slot antenna showed a moderate gain and bandwidth of 2.9 dBi and 13.1%, respectively. The PIFA achieved the widest bandwidth of 31% but the smallest gain of 1.2 dBi. Furthermore, the performance deterioration of the proposed antennas under various bending conditions was analyzed to evaluate their suitability for wearable applications. Moreover, two 2 × 2 patch and slot antenna arrays were assembled to increase gain and bandwidth. The measured results proved that the developed antenna designs provide superior performance.