Textile Antennas for Spacesuit Applications: Design, simulation, manufacturing, and testing of textile patch antennas for spacesuit applications

This article presents the design, simulation, manufacturing, and testing of textile patch antennas for spacesuit applications at the frequency 2.45 GHz. Antennas are designed for dispersed placement on two suit prototypes, NDX-1 and NDX-2, both external to the suit and mounted on the inner wall of a removable, thermal layer. Movement of the wearer, along with the necessity of compact transport and the harsh conditions of the extraterrestrial environment, call for durable and flexible antenna materials. Nickel-copper ripstop was selected as the best material for the patch and ground, and layered ultrafirm fabric stabilizer was used for the dielectric. Spray adhesive joined the patch to substrate to ground. Several rounds of antenna design and manufacture were carried out to create the best-performing design. This design of this patch is 52.122-mm long, 58.375-mm wide, with substrate dimensions of 127.52 mm x 127.52 mm, with a height of 1.6 mm. Simulation and experimental results, including co- and cross-polarization patterns in the E- and H-plane and return loss for planar and conformal antenna configurations are presented and discussed. Results indicate that minimal antenna flexure (radius = 101.6 mm) slightly degrades antenna performance and causes a shift in resonant frequency up to 0.02 GHz. Increased flexure (down to a 43.2-mm radius), did not significantly alter radiation patterns or return loss. Extreme bending (<43.2-mm radius), while not quantified in this article, resulted in severely degraded performance, thus placement of antennas on the suit must limit antenna flexure to ensure desired performance.