Electrical Properties of Human Tissues Applied to Wearable Antenna Design

A method for designing wearable antennas at microwave frequencies is presented in this thesis. An antenna placed on the human body is heavily influenced by the electrical properties of tissues. Thus, the proposed method includes of the development of mixtures that mimic the electrical properties of human tissues in order to validate the antenna designs. Simulation of several printed antennas in the presence of tissues are performed and analyzed The work outlines the process of developing phantom tissues and their validation using an open-ended coaxial probe method. A guide-wave permittivity measurement method and a free space measurement method are also discussed. The results show lower values than expected for the complex permittivity compared to those previously published. Some reasons for the discrepancy are suggested. Two prototype antennas are developed: a rectangular patch antenna and a dipole. A layered stack model of tissues is compared to a simpler and computationally more efficient half space model. The effect of the separation between the antenna and the tissues, the bending of tissues and the variation of tissue electrical characteristics are analyzed and quantified. The separation or bending of the tissues greatly influence the performance of the antenna, as expected