Evaluation of the effect of bending on the resonance frequency of inset-fed rectangular textile patch antenna

Abstract

This paper presents a study on the bending behavior of rectangular textile patch antennas including analytical modeling, full wave simulations, and experimental measurements. In the proposed analytical model, the textile patch antenna was treated as a laminated composite beam. Therefore, after locating the position of neutral axis considering the tensile modulus and the dimensions of each layer, the classic cylindrical cavity model was modified to predict the relation between resonance frequency and bending curvature, taking into account the patch’s elongation. Since the presented interdisciplinary analytical approach is associated with a set of simplifying assumptions, a full wave model was also utilized to study this effect. All the simulations were performed in two modes; patches with fixed and elongated dimensions. Finally the results of both models were compared with the experimental measurements and the effects of bending on the resonance frequency of textile patch antennas were discussed in more detail. The obtained results showed that some parameters including the direction of bending, substrate thickness, and mechanical properties of antenna’s components can alter the textile patch antenna’s behavior under bent conditions.