Flexible antenna array for wearable head imaging system

In this paper, a flexible directional monopole antenna for wearable head imaging system for stroke detection is presented. To ensure better flexibility for wearable applications, a very thin flexible PET substrate, Melinex 339 with thickness of 75μm is utilized. The size of the antenna is 70mm × 30mm. An array of 8 antennae are arranged in elliptical configuration to follow a human head contour. The antennae operate at frequency of 1.3GHz to 3.5GHz which would provide sufficient penetration and resolution. These antennae were designed and optimized to work in close proximity with human head. An investigation on mutual coupling between neighboring antennae when in close proximity with artificial human head and on free space is carried out via CST Microwave Studio and experimentation. Specific Absorption Rate (SAR) with different transmitted power level are simulated to ensure that the electromagnetic wave absorbed by human head is below the safety limit.