Fabrication and packaging of flexible and breathable patch antennas on textiles

Abstract

Textile antennas are prone to damage and change their shape and RF (radio frequency) characteristics over time. However, typical hydrophobic coatings or encapsulation layers, such as polyurethane, acrylate, or films, make textile antennas rigid and air impermeable. This work details the approach of using a polyurethane web as an encapsulation and lamination layer for screen-printed microstrip patch antennas on textile fabrics. Integrating the polyurethane web into the textile antennas makes the printed antennas flexible, air permeable, and durable. Further improvements are made by introducing a novel porous patch antenna design to enhance the flexibility and air-permeability for printed antennas. Antennas were designed and modeled using the ANSYS HFSS simulation software and compared with fabricated experimental results. Results show the fully packaged printed antenna have good impedance matching even under different bent conditions. The antennas were also analyzed before and after rinsing with heavy flow of water for 2 minutes to determine the effect of wetting.