PolarFix: Fixing Polarization Mismatch for UAV mmWave Communication Enhancement

Millimeter-wave (mmWave) communication offers a promising solution for high-throughput, low-latency unmanned aerial vehicle (UAV) networks. However, maintaining strong received signal strength (RSS) remains a challenge due to UAV mobility. While existing studies have largely focused on beam alignment, they often overlook another critical issue: polarization mismatch caused by UAV orientation changes. This problem is particularly severe in cost-sensitive commercial off-the-shelf (COTS) mmWave devices, which typically employ linearly polarized (LP) antenna arrays. Our measurements reveal that even with perfect beam alignment, UAV orientation can still cause significant signal degradation due to polarization mismatch. To address this challenge, we propose PolarFix, a practical metasurface solution that enables real-time polarization matching without requiring any modifications to existing transceiver hardware. Specifically, we design a linear-to-circular polarization (L2C) metasurface that transforms linearly polarized (LP) waves into circularly polarized signals, allowing LP antennas to maintain consistent signal power despite changes in UAV orientation.