A Systematic Investigation of Rectangular Patch Antenna Bending Effects for Wearable Applications

The emerging applications for wearable electronics have experienced enormous growth over the last decade. Antennas, being one of the critical components in modern wireless devices, thus need to be specifically designed to function while being worn and bent. In this paper, we present a systematic investigation of the effects of bending applied on wearable patch antennas over cylindrical surfaces. The resonant frequency variations and radiation pattern variations have been studied by simulating and measuring patch antennas that are bent by different angles. A frequency shift plot with respect to bending radius has been generated to target antennas for various wearable applications. An analytical approach has been presented to study the effect of resonant frequency shifting for both E- and H-planes bending. A lumped element circuit model is used to interpret the E-plane bending from different perspectives. One of the main objectives of this paper is to develop useful design-oriented charts and provide a better understanding of the effects of antenna bending to assist wearable antenna designers.