Two Novel Low Energy Mechanically Reconfigurable Antennas Based on Chladni and Moiré Patterns

Abstract

In this thesis, two mechanically reconfigurable antennas are proposed. The first antenna is based on the moiré phenomenon, where the relative rotation of two superposed layers produces new topologies. The two patches are circular, fabricated on an FR4 substrate with a layer of copper. The patterns are horizontal lines milled into the substrate. The actuation mechanism relies on a ratchet mechanism and is actuated by a shape memory alloy (SMA) spring. The simulations and measurement of the fabricated prototype show polarization reconfiguraton, along with a beam focusing effect at high rotation angles. The second design concept relies on the vibration of conductive grains on top of a patch antenna to create different patterns. These shapes of the standing waves, known as Chladni patterns, are obtained by exciting a thin plate at different frequencies. The effect of these patterns on the antenna characteristics depends on several factors that still need to be investigated and analyzed.