Polarization design of microwave wireless transmission systems for moving targets

Microwave wireless power transfer (WPT) technology enables the efficient, contactless transmission of energy through electromagnetic waves, with widespread applications in wireless charging, remote energy transmission, and satellite-based power harvesting, holding significant social, economic, and environmental implications. A ground-to-air WPT system is presented as a sample, this study investigates the impact of antenna polarization modes on the transmission efficiency of WPT systems for moving targets. Numerical simulations of transmission coefficients are conducted under various deflection angles, with transmission distances at both near-field (103 mm) and far-field (350 mm). The three polarization modes are single-line polarization (SL), dual-line polarization (DL), and circular polarization (CP). The results show that the polarization configuration with a single-line polarized transmitting array and a dual-line polarized receiving array (SL-DL) exhibits superior transmission efficiency. In the near field (103 mm), the linear transmission coefficient values of SL-DL are on average 0.08 and 0.06 higher compared to SL-SL and CP-CP at various angles, respectively. In the far field (350 mm), the corresponding transmission coefficient values increase by an average of 0.02 and 0.016.