A novel Partially Reflective Surface (PRS) antenna
is proposed, which can electronically alter its polarization
between linear polarization (LP), left-hand circular polarization
(LHCP), and right-hand circular polarization (RHCP). The
antenna consists of a shorted annular patch (SAP) antenna as
the source, a PRS structure to enhance the gain, and a
reconfigurable Wilkinson power divider as the feed network.
