Polarization-Tilt-Insensitive Microwave Wireless Power Transmission by Orthogonal Excitations

Polarization misalignment between transmitting (TX) and receiving (RX) antennas inevitably leads to severe degradation of wireless link. To guarantee an aligned polarization propagation, TX and RX dual-linearly polarized (DLP) antennas are employed. When two orthogonal signals are excited at horizontally polarized (HP) and vertically polarized (VP) ports of the TX DLP antenna, polarization-tilt-insensitive microwave power transmission can be achieved at both HP and VP ports of RX antenna, which allows maximum RF-to-dc rectification by two parallelly dc-combined rectifiers. Selected distances (50 and 100 cm) and polarization tilts ( $\varphi $ varies from 0° to 90° with $\Delta \varphi = 30^{\circ }$ ) are carried out for experimental measurements, which along with theoretical analysis validates its effectiveness of such polarization-tilt-insensitive microwave power transmission by orthogonal excitations.