Flexible Quasi-Yagi antenna arrays for wearable electromagnetic head imaging based on polymer technology

A flexible, low profile, compact and wideband planar quasi-Yagi antenna array is proposed for a wearable electromagnetic head imaging system. The array is designed on a low cost, high-flexibility, and robustness polymer polydimethylsiloxane (PDMS) substrate and is optimized to operate in a low microwave frequency band of 1.63 GHz-2.66 GHz. An array of 12 antennas is configured and embedded in a polymer-based 3D elliptical structure which is wearable. Numerical simulations using CST Microwave Studio are performed in free space, on a realistic (Hugo) human head model, and under folded conditions. The simulations results show that the proposed antennas exhibit 51% impedance bandwidth, a maximum gain of 3 dB, more than 83% of radiating efficiency and > -14 dB mutual coupling between neighboring antennas.