  This work presents a beam-steering reflectarray antenna capable of achieving
arbitrary linear polarization (LP) reconfiguration. It utilizes a dual-circular
polarization (CP) reconfigurable reflectarray, along with an LP feed horn, to
synthesize a LP beam by combining two reflected CP beams in the same direction.
The LP states can be dynamically adjusted by tuning the phase constants of the
array, which correspondingly modify the wave phases. Experimental validation of
the proposed polarization synthesis concept is conducted using a 16$\times$16
dual-CP 1-bit reconfigurable reflectarray operating at 16.8 GHz. This
reflectarray generates reconfigurable LP waves with polarization states of
LP(0$^\circ$), LP(45$^\circ$), LP(90$^\circ$) and LP(135$^\circ$). Furthermore,
it demonstrates the capability to perform beam scanning, allowing for versatile
beam manipulation. The application of this polarization-reconfigurable
beam-steering reflectarray is pertinent to beam alignment and polarization
synchronization in various wireless communication scenarios, including
satellite communication and mobile communication.
