Electronically switchable multi-polarization circular patch antenna for conformal arrays

A novel reconfigurable antenna structure allowing polarization rotation is proposed. The antenna is a linearly polarized aperture coupled circular patch antenna, with three independent radial feeding lines allowing to rotate the polarization in steps of sixty degrees. The desired polarization sense is achieved by turning on the PIN diode at the beginning of the appropriate feeding line. Measured results show good matching and low cross-polarization levels, and agree well with the theory. The proposed architecture can be advantageous for use in doubly curved antenna arrays, where the possibility to align element polarizations directly translates into an increased array gain.