Functionally adaptive smart metasurface window with Weber beams for obstacle-avoiding communications in vehicle cabin.

The integration of non-diffracting beams with metasurfaces offers exceptional potential for advanced wave control, yet their practical deployment in communication systems, especially those requiring optical transparency, has remained largely unrealized. Here, we propose a transparent metasurface as a smart window that bridges this gap by generating self-accelerating Weber beams for robust in-vehicle wireless communications. Fabricated via a low-cost printed circuit board (PCB) process on flexible polyethylene terephthalate (PET) substrates, the smart window achieves 73.5% optical transmittance and efficient microwave cross-polarization conversion. Two beam types, i.e. orthogonal and semi-auto-focusing Weber beams, are tailored for lateral and rear windshield integration, both exhibiting self-bending and self-healing capabilities. In real-world vehicle cabin tests, the metasurface-enhanced system significantly improves the link reliability under physical obstruction, yielding an average enhanced power of 8.37 dB and reduced bit error rate below 1% with successful high-fidelity RGB image reconstruction. This work establishes a practical framework for transparent electromagnetic interfaces that dynamically reroute the wireless signals, with promising applications in smart vehicles, building-integrated communications, biomedical devices and industrial Internet of Things.