Decoupling Backward Scattering Control and Forward Beamformed Communication in a Shared-Aperture...

Integrating electromagnetic scattering engineering and high-quality wireless links on the same platform is fundamentally challenged by the coupling between reflection and transmission channels in shared-aperture structures. Here we report a programmable retro-reflective and transmissive metasurface (RRTM) that decouples backward scattering enhancement from forward beamformed communication within a single co-aperture. A four-state meta-atom using two embedded positive-intrinsic-negative (PIN) diodes provides 1-bit phase control in both reflection and transmission channels, enabling unified digital coding for dual functionalities. A 16 × 16 prototype is driven by a field-programmable gate array (FPGA) and cascaded shift registers for rapid reconfiguration among transmissive beam steering, retro-reflective scattering enhancement and hybrid operation. Experiments at 8 GHz validate wide-angle transmit beam steering up to ± 60° and angular-adaptive retroreflection up to 50° incidence. A video transmission link with a well-clustered 16-ary quadrature amplitude modulation constellation further confirms the quality of beamformed communication. Finally, a checkerboard co-aperture coding strategy enables simultaneous retroreflection and transmit beam scanning, preserving narrow beams and low sidelobes in concurrent operation. The proposed architecture provides a practical route toward integrated platforms that require coordinated scattering control and directional wireless links.