Textile Slotted Waveguide Antennas for Body-Centric Applications

Abstract

One of the major challenges in the development of wearable antennas is to design an antenna that can at the same time satisfy technical requirements, be aesthetically acceptable, and be suitable for wearable applications. In this paper, a novel wearable antenna is proposed—textile realization of a slotted waveguide antenna. The antenna is realized using conductive fabric to manufacture the walls of a rectangular waveguide in which the slots were cut out. All connections and cuts are sewn with conductive thread taking over advantages of the traditional process of manufacturing textile objects. The developed slotted waveguide array prototype, containing three slots and designed for operation in the 5.8-GHz ISM band, is experimentally characterized and compared to an equivalent metallic antenna. The achieved operating bandwidth is larger than 300 MHz in both cases. The measured gain of a textile slotted waveguide array is around 9 dBi with a radiation efficiency larger than 50% in the whole operating bandwidth, i.e., the textile array showed a 2 dB lower gain in comparison to the metallic counterpart. The gain is stable in the whole bandwidth and the radiation patterns do not differ. The results demonstrated that such textile antennas are suitable for body-centric communication and sensor systems and can be integrated into clothing, e.g., into a smart safety vest or into a uniform. Further analysis of various realizations of slotted waveguide antennas is presented showing that different versions of the proposed antenna can be used in all three off-body, on-body, and in-body communication scenarios.

The Influence of Textile Substrates on the Performance of Textronic RFID Transponders

“…Some of them concern constructions that are dedicated to the unlicensed ISM (Industrial Scientific Medical) bands. Typically, these antennas are made by combining (a) classic conductive materials with a textile base (e.g., copper foil or screen-printed layer on cotton [ 14 ] and other substrates [ 15 ]) or (b) innovative conductive textile materials (e.g., conductive polymers, electrotextiles, graphene sheet, fabrics with metal threads [ 16 , 17 ]) with classic textiles (e.g., graphene sheet with denim or felt [ 13 , 18 ]). In addition, the integration of a typical flexible antenna (e.g., made on polyethylene terephthalate PET foils) with fabrics is frequently used [ 18 , 19 ].…”

Design and Analysis of Fabric Antenna for Medical and Wireless Applications

“…These challenges provide hindrances in the reliability and development of wearable devices for body-centric communications. 4,5 The human body’s effect on the various parameters of the antenna has been analyzed through homogeneous 6–9 and heterogeneous human models. 10,11…”

Dual-Band Self-Complementary 5G Antenna for Wireless Body Area Network

“…The exponential growth of wireless communication as well as technological advancement is reflected by the extraordinary success of wireless mobile communications in recent years [1,2]. The first generation's analog wireless communication supported only voice calls, which was introduced in the 1980s and evolved to the second generation's digitalized code-division multiple access (CDMA) and global system for mobile communication (GSM) telecommunication in 1991.…”