Polymer micro-actuator for frequency agile patch antenna

In this paper, we present a new generation of microstrip patch antenna using a recyclable and low cost soft polymer, the polyurethane (ε_r ≈ 3.5 at 10 GHz) (PU), as a part of dielectric substrate. The combination of simple membrane manufacturing process and the low Young´s modulus of PU (E_PU ≈ 30 MPa) are employed in the X-band antenna application. Membrane supported technology is used to reduce the influence of this high dielectric loss (tan δ ≈ 0.1 at 10 GHz) and gives higher antenna radiation efficiency (η ≈ 31.7 %). Besides, membrane deflection allows frequency tunability of the antenna up to 4.17 %. At last, the interest of patterning the metallic patch was discussed in order to increase actuation performance.