Wearable Folded Planar Dipole Antenna: Design and assessment for on-body wireless communication devices

A folded planar dipole antenna was designed and customized to operate close to the human body. Backward radiation was reduced to protect the human body from unwanted electromagnetic (EM) emissions and increase the antenna's operating range. The antenna design was based on the concept of a folded planar dipole, which presents favorable impedance bandwidth (BW) characteristics. For integrability and robustness during usage in real environments, the antenna was completely covered by resin, taking into account the tradeoff between the antenna's radiation performance, protection, and isolation. Measurements demonstrated a 10-dB impedance BW of 470 MHz (18.76%) covering the 2.27-2.74-GHz band. The maximum gain at 2.45 GHz was 1.4 dB isotropic (dBi). The antenna has a nearly omnidirectional pattern, occupies 77 x 35 x 11.15 mm, and weighs 120 g, making it easy to integrate with clothes. The resin packaging increased the mechanical robustness and improved the design's isolation from external interference and perturbations; however, it reduced the radiation efficiency to 48.35%. The presented antenna is an excellent candidate for many wireless applications, in particular, applications where withstanding exposure to external mechanical strains and EM perturbations is required.