All-textile higher order mode circular patch antenna for on-body to on-body communications

An all-textile higher order mode circular patch antenna for on-body to on-body communications is proposed. The proposed antenna is compact in size and consists of a coaxially centre-fed circular patch with two shorting vias to generate the TM₂₁ higher order resonance mode for a monopole-like radiation characteristic. The antenna is fabricated by using a conductive textile, conductive thread and a felt substrate. The bandwidth can fully cover the 2.45 GHz ISM band while achieving a low-profile configuration. The effects of antenna deformation because of bending and the human body are analysed when the antenna is placed on a two-thirds muscle-equivalent phantom and a full-scale human model. The performance of the antenna is minimally affected by antenna deformation and the human body because of the TM₂₁ higher order mode excitation and its monopole-like radiation pattern.