A Substrate Integrated Fluidic Compensation Mechanism for Deformable Antennas

This work presents the design, theory, and measurement of a linearly polarized microstrip patch antenna with a substrate-integrated compensation mechanism to mitigate the detuning effects from a physical deformation (e.g., bending and twisting). In particular, we investigate the ability of an antenna to maintain its impedance bandwidth as it bends sharply through the center (from flat up to 90deg pivoted about the ground plane). Compensation for this bending occurs through the displacement of electromagnetically functionalized colloidal dispersions (EFCDs) in a substrate-embedded capillary. Stability of the 2:1 VSWR (matched impedance) bandwidth has been examined numerically across the entire range of bending, and demonstrated experimentally using fixed-bend patch antennas on 4 mm thick isocane foam substrates to illustrate this concept.