Printed textile metasurfaces for gain and directivity enhancement

Abstract Wearable printed electronics are of significant recent interest for use in on-body communication devices, including antennas that are readily integrated into textiles using additive manufacturing. Directly printing the device onto textile reduces the need for costly, time-intensive processing steps; however, textile substrates impose design and performance limitations given that the design must be compatible with on-body usage and must also remain below maximum safe radiation levels. Herein, we present a passive solution for improving the performance of a commercial off the shelf omnidirectional antenna using textile metasurfaces. A modular system was developed for gain enhancement and pattern shaping using three metasurface elements with a band stop resonance at 6 GHz, where reflection is used to enhance gain. The versatility of a wearable metasurface is demonstrated for two of the designs which also offer a band pass at 2.4 GHz. Radiation pattern measurements conducted in an anechoic chamber showed that the metasurface achieved a gain improvement of up to 7.2 dB. This methodology enables a wearable, low-profile, passive, and non-destructive system for the improvement of existing wearable communication devices.