Design of Circular Polarization Radiation Pattern Reconfigurable Rectenna for IoT Devices

A compact metasurface-integrated reconfigurable antenna operating in the Sub-6 GHz frequency band, at 4.8 GHz, for wireless power transfer (WPT) applications is presented. By controlling PIN diode switches on the metasurface and ground layer, the antenna achieves beam steering within ±36° and switches between left-handed (LHCP) and right-handed circular polarization (RHCP). Experimental validation demonstrates the axial ratio below 3 dB, confirming effective circular polarization performance. The gain of the main lobe is 5- 6 dBi. This type of rectenna is particularly suitable for IoT wireless power transfer applications, enabling efficient power delivery to dynamically positioned devices through adaptive beamforming and polarization agility.