Flexible and Textile Antennas for Body-Centric Applications

Abstract

The recent years have witnessed increased research activities focused on the development and optimization of flexible electronics in response to the market trends that report a growing interest in portable, lightweight, low-profile, and flexible electronic devices. Flexible and wearable antenna designs have received significant attention due to the dramatically increasing demands in various wearable electronic systems. Several research efforts have focused on developing flexible, cost effective and planar ultra-wideband (UWB) and millimeter wave (mmWave) antennas for wearable applications. A wide range of flexible materials used for the purpose include polymers, paper, novel materials for substrates and copper foil, silver nanoparticles for the conductive region of the antennas have been reported in this chapter. Apart from flexible substrate antennas, the textile-based antennas have also been described which can be directly integrated into the cl’othing. Several fabric-based patch antennas have been introduced in this chapter considering a variety of materials that have been chosen for antenna design such as felt, denim cloth, cotton cloth, nylon etc. and conductive threads for the radiating structures. Various cost-effective and novel fabrication techniques are applied for the design of such antennas which have been described in this chapter. Electromagnetic characterization of the ultra-wideband and mmWave antennas has been carried out in free space and on-body scenarios in terms of return loss, gain, efficiency, radiation patterns, signal fidelity etc. Mechanical sustainability and durability have also been reported for various antenna designs through flexibility tests such as bending and crumpling.