All-Textile PIFA Suits Wireless Body Area Networks

Textile antennas are attractive for emerging applications in “wearable wireless” systems, such as in wireless body-area networks (WBANs). Ping Jack Soh and Guy Vandenbosch of Katholieke Universiteit Leuven (Leuven, Belgium), along with Soo Liam Ooi and Nurul Husna Mohd Rais of Universiti Malaysia Perlis (Perlis, Malaysia), pursued the design and development of an all-textile antenna design based on a planar inverted-F antenna (PIFA) architecture. The team’s design featured a slot on the radiator for operation on the 2.45-GHz ISM band.

The antenna was designed and fabricated with two types of conducting textile materials and a 0.035-mm-thick conductive copper foil tape. Both of the commercial conducting textile materials feature high conductivity. The antenna design was based on two conductive layers shorted by a wall. The substrate was a 6-mm-thick felt fabric placed between the ground plane and the radiating patch. The substrate exhibited a relative dielectric constant of 1.43 at 2.4 GHz with loss tangent of 0.025 in the z-direction at the same frequency. The design exhibited a bandwidth as wide as 1200 MHz in free space and as much as 1300 MHz when worn on a body, showing great promise. See “Design of a Broadband All-Textile Slotted PIFA,” IEEE Transactions on Antennas and Propagation, Vol. 60, No. 1, January 2012, p. 379.