A novel scheme for realizing a microstrip antenna with switchable circular polarization

The design of a single-fed circularly-polarized microstrip antenna with switchable polarization, using a metal-plated dielectric slug, is described. The scheme of micro-pneumatical control of a solid slug presents an alternative to the existing methods in realizing reconfigurable antennas. The position of the slug underneath the patch determines the polarization of the antenna radiation. This proximity-coupled-fed antenna is simulated and the results demonstrate the viability of the design. Sensitivity to fabrication tolerances is also addressed.