Design of wide band circularly polarized textile antenna for ISM bands at 2.4 and 5.8 GHz

This paper describes the design and fabrication of circularly polarized wideband textile antenna resonating at 2.4 GHz and 5.8 GHz ISM bands. The textile antenna that is designed for wireless body centric communications should be low profile, light weight, comfortable against skin and unobtrusive to be worn so that it can be easily accepted by the general public. With the advent and easy availability of electrotextile materials it is now possible to fabricate textile antennas that are very suitable to be used for portable applications. Here, conductive metalized nylon fabric (Zell) is used as a conducting material. For increasing the flexibility and comfortability to the user, denim is used as a substrate material. The proposed antenna is optimized on software package CST microwave studio 2011 for larger bandwidth. It has been found that this circularly polarized antenna has very high 3-dB axial ratio bandwidth and -10 dB impedance bandwidth in free space with very high gain in both ISM bands. The antenna prototype is finally checked on the human body and free space with VNA. The obtained results have validated the design idea.